RU2574441C2 - Forward scanning at boring chisel use - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: method is suggested to perform measurements in the well that contains the following stages: actuation control for the device placed in the well and having assembly of radiating and receiving antennas placed at distance and capable of operation in selected pairs of radiator and receiver. At that deep-earth signal is recorded from deep-earth measurement using a pair of radiator and receiver, and one or several shallow-earth signals are recorded using one or several other pairs of radiator and receiver; one or several shallow-earth signals are processed, a model signal is generated in regard to areas joining side walls and rear side of the device; and forward-scanning signal is generated in essence without contribution from the areas joining the device by means of deep-earth signal processing depending on the model signal. The invention also suggests a device for measurements in the well and machine-readable memory unit with instructions to perform actions in the above method.

EFFECT: improved sensitivity and data accuracy in process of measurements in the well.

31 cl, 41 dwg

Description

Technical field

In General, the present invention relates to systems with the ability to perform well logging.

BACKGROUND OF THE INVENTION

When drilling wells for oil and gas exploration, understanding the structure and properties of the geological formation surrounding the wellbore provides information to facilitate such exploration. However, the environment in which the drilling tools operate is located at a considerable distance from the surface, and the measurements necessary to control the operation of such equipment are performed at the equipment installation sites. Logging is the process of taking measurements with sensors located in the well that can provide valuable information regarding the characteristics of the formation. In the measurement methods, electromagnetic signals can be used, with which you can perform in-depth measurements, which are less affected by the wellbore and the effects of the area covered by drilling, and shallow measurements near the instrument generating the probing signals. Typically used instruments are placed above the drill motor on the drill string and take measurements from formations that have already been drilled by the drill bit. In addition, the usefulness of such measurements may depend on the accuracy or quality of the information obtained as a result of such measurements.

Brief Description of the Drawings

In the drawings: 3

FIG. 1 is a block diagram of an example of a device having a device for performing measurements in front of a drill bit, according to various embodiments;

FIG. 2 shows the steps of an example look-ahead method for bit applications in a drilling operation according to various embodiments;

FIG. 3A and 3B illustrate the calculation of the look-ahead signal according to various embodiments;

FIG. 4A and 4B illustrate the effect of suppressing signals from layers according to various embodiments;

FIG. 5A and 5B illustrate combined geometric factors for an instrument according to various embodiments;

FIG. 6 is an illustration of combinations of tilt angles at which the effect of suppressing signals from the layers for different incidence angles is achieved, wherein the incidence angle of incidence is aligned with respect to dipoles, according to various embodiments;

FIG. 7 is an illustration of combined geometric factors for a high conductivity medium according to various embodiments;

FIG. 8 is an illustration of geometric factors associated with two different spacings, according to various embodiments;

FIG. 9A-9C are three example configurations with suppression of signals from layers and corresponding sensitivity areas according to various embodiments;

FIG. 10A and 10B are examples of basic configurations of deep measurements and shallow measurements according to various embodiments;

FIG. 11 is an illustration of a comparison of periodic differential measurement and suppression measurement of signals from layers according to various embodiments;

FIG. 12 is an example of a data recording system according to various embodiments;

FIG. 13 shows the steps of an example of a method for calculating a look-ahead signal using shallow and deep inversion according to various embodiments;

FIG. 14 shows the steps of an example of a method for calculating a look-ahead signal using only shallow signals according to various embodiments;

FIG. 15 is an example of computing a look-ahead signal using deconvolution according to various embodiments;

FIG. 16 is an example of calculating deep layer properties using full inversion according to various embodiments;

FIG. 17 is an example of calculating deep layer properties using a simple inversion according to various embodiments;

FIG. 18 is an example of calculating deep layer properties using inversion according to various embodiments;

FIG. 19 is an example of a decision chart for geosteering according to various embodiments;

FIG. 20 is an illustration of geometric factors associated with two different distances between the emitter and receiver, according to various embodiments;

FIG. 21 is an illustration of a non-causal inverse filter according to various embodiments;

FIG. 22 is an illustration of a causal inverse filter according to various embodiments;

FIG. 23 and 24 are an illustration of a synthetic well log (in each figure) at a zero dip angle and four layers during inversion, according to various embodiments;

FIG. 25 is a four-layer synthetic well log in the process of performing deconvolution according to various embodiments;

FIG. 26 and 27 show a comparison of a standard configuration and a configuration with suppression of signals from layers for the case of a large number of layers with a variation in resistivity according to various embodiments;

FIG. 28A-C are an example of a step response and examples of differential signal models according to various embodiments;

FIG. 29 is an illustration of a skin effect corrected signal for a typical case according to various embodiments;

FIG. 30A-B is an illustration of the inverted ranges to the boundary and the conductivity contrast for a typical case according to various embodiments;

FIG. 31 is a block diagram of an example system for controlling activation of an antenna arrangement and processing received signals during look-ahead for bit applications according to various embodiments; and

FIG. 32 is an illustration of an embodiment of a system at a rig site in accordance with various embodiments.

Detailed description

The following detailed description is associated with the accompanying drawings, in which, for illustration and not limitation, various embodiments are shown in which the invention can be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to put into practice these and other embodiments. Other embodiments may be used, and structural, logical, and electrical changes may be made to these embodiments. Various embodiments are not necessarily mutually exclusive, as some embodiments may be combined with one or more other embodiments to form new embodiments. Therefore, the following detailed description should not be construed in a limiting sense.

In FIG. 1 is a block diagram of an apparatus 100 according to an embodiment having an instrument 105 for performing measurements in front of a drill bit, which can be used to detect a look-ahead signal and to determine properties in a well 102. The apparatus 105 may have an arrangement of emitters and receivers 110-1, 110- 2, ..., 110- (N-1), 110-N, distributed along the longitudinal axis 107 of the device 105. These emitters and receivers can perform the function of capturing signals near the device 105, in the areas behind the device 105 and in the areas adjacent to the sides Am instrument 105. These signals from relatively small ranges can be called shallow signals. In addition, these emitters and receivers can perform the function of capturing signals in the areas in front of the tool 105, and when the device 105 is located on the drill structure, the signals captured in front of the device 105 can come from the areas in front of the drill bit. These signals from relatively large ranges, from greater depths compared to shallow signals, can be called deep signals. For the operation of the arrangement of emitters and receivers 110-1, 110-2, ..., 110- (N-1), 110-N, you can choose a pair of emitter-receiver with a given distance between the emitter and receiver in each corresponding pair. Long distances can be used for sounding in front of the drill bit and recording deep signals. Smaller distances can be used to probe areas of the formation around the tool 105. The deep signal and shallow signal can be in accordance with the distance of the emitter-receiver, which, in turn, can be determined by the position of the emitters and receivers behind the drill bit. For example, a shallow measurement may include contributions from areas located at a distance of from about 1 inch (25.4 mm) to about 10 feet (3 m) from the instrument, and a deep measurement may include contributions from areas located at a distance from about 5 feet (1.5 m) to about 200 feet (61 m) from the appliance. When performing shallow and deep measurements, deep measurements include contributions from areas farther from the instrument than shallow measurements. For example, without limiting the value indicated below in depth measurements, there may be contributions from distances from the instrument that are at least 25% greater than the distances from which contributions to shallow measurements are provided. The difference in investment investment distances may be less or more than 25%.

The arrangement of the radiating antennas and receiving antennas can be distributed along the longitudinal axis 107 of the tool 105, which is essentially perpendicular to the cross section of the device corresponding to the cross section of the drill collar in the drill string. The arrangement may include emitters and receivers spaced from each other so that one of the emitters or receivers is located closest to the drill bit, and the last of the emitters or receivers in the arrangement is farthest from the drill bit. One transmitter or receiver closest to the drill bit can be positioned as close to the drill bit as possible. The closer the layout starts to the drill bit, the farther the formation properties can be determined from the drill bit. The first antenna can be placed on a weighted drill pipe behind the drill motor. Alternatively, the first antenna may be placed on a drilling engine, rather than on a weighted drill pipe behind the drilling engine.

The transmitter-receiver pairs can be arranged on the device 105 with orientation relative to the longitudinal axis 107 of the device 105 by using a certain combination of the tilt angle of the emitter and the tilt angle of the receiver, at which signals from the layers between the respective emitter and the receiver from the pair can be suppressed. The angle of inclination of the emitter may be the same as the angle of inclination of the receiver, or may differ from the angle of inclination of the receiver. For example, the receiver may have a zero angle of inclination, and the emitter may have a non-zero angle of inclination. This arrangement of the emitter and receiver on the device 105 can make the device 105 insensitive to the properties of the area on the side of the device. To eliminate effects around the device and focus in front of the bit, it is possible to implement processing of signals recorded at the receiver from a pair in response to a probe signal emitted by an emitter from a pair. The arrangement of the emitters and their respective receivers with the formation of an orientation at which signals from specific layers are suppressed can be realized for a given angle of incidence. In the case of emitters and their respective receivers arranged to form an orientation for a zero angle of incidence, at which signals from specific layers are suppressed, operation at a different angle of incidence can lead, for example, to incomplete suppression of signals from the layers. However, there may be a range of incidence angles different from the incidence angle, according to which the emitter and receiver are arranged to substantially completely suppress signals from the layers, at which signals from the layers are substantially suppressed. Suppression essentially may include 90% suppression relative to optimal suppression. The number of emitters and receivers 110-1, 110-2, ..., 110- (N-1), 110-N of the device 105 may be sufficient to form pairs of emitter-receiver with different orientations, so that the optimal suppression of signals from the layers can be obtained using the device 105 for a number of different angles of incidence.

Advance measurements to obtain a look-ahead signal or determine formation properties in front of the drill bit can be performed by the device 105 without using oriented emitter-receiver pairs, so that when emitter-receiver pairs work, signal suppression from the layers will not be provided. Data from one or more shallow measurements can be subtracted from the depth measurement to obtain a leading measurement. Look-ahead data can be processed to receive the look-ahead signal and to determine formation properties in front of the drill bit.

Instrument 105 may have multiple antennas arranged in pairs. The first transmitter-receiver antenna pair may have a distance between the transmitter and receiver of the first transmitter-receiver antenna pair ranging from two feet (0.6 m) to twenty feet (6 m) to perform such shallow measurements in which the signals from the layers are essentially are suppressed between the emitter and the receiver of the first antenna pair of the emitter-receiver. The second transmitter-receiver antenna pair may have a distance between the transmitter and receiver of the second transmitter-receiver antenna pair ranging from twenty feet (6 m) to one hundred feet (30 m) to perform depth measurements such that signals from the layers are substantially suppressed between the emitter and receiver of the second antenna pair of the emitter-receiver. The radiating antenna of the first antenna pair of the emitter-receiver is arranged as the radiating antenna of the second antenna pair of the emitter-receiver or the receiving antenna of the first antenna pair of the emitter-receiver is located as the receiving antenna of the second antenna pair of the emitter-receiver.

The device 100 may include a control unit 120 for controlling the excitation of the emitters of the device 105 and the reception of signals by the receivers of the device 105. The control unit 120 may be adapted to perform operations on selecting antennas from multiple antennas in one or more pairs of emitter-receiver located to perform one or several deep measurements and one or more shallow measurements when the device is operating inside the well. The control unit 120 may be adapted to perform operations on selecting antennas from multiple antennas in one or more emitter-receiver pairs located to substantially suppress signals from the layers between the emitting antenna and the receiving antenna of the corresponding emitter-receiver pair when the device is operating inside the well. Along with other work using a radiating antenna and a corresponding receiving antenna, the control unit 120 may be adapted to perform absolute depth measurement, relative depth measurement with an additional receiver or compensated depth measurement with an additional receiver and additional emitter, so that the signals from the layers will be essentially suppressed between antenna pairs of the emitter-receiver with appropriate measurements. The control unit 120 may control a device 105 having four antennas located for performing shallow measurements and depth measurements, and as a result of the operation of the four antennas, signals from the layers will be substantially suppressed. The control unit 120 may control the device 105 having fewer than four antennas located for performing shallow measurements and depth measurements, and in this case, as in the case of four antennas, signals from the layers will be substantially suppressed. The control unit 120 may work in conjunction with the data processing unit 126 to process the signals received from the receivers in the device 105.

The data processing unit 126 may be adapted to perform data processing operations on one or more in-depth measurements and one or more shallow-depth measurements to produce a look-ahead signal substantially without contributions from areas adjacent to the sides of the device. The data processing unit 126 may include tools for performing one or more methods of processing signals from shallow measurements and signals from deep measurements to form a look-ahead signal. The look-ahead signal is defined as the signal correlated with the area in front of the drill bit associated with the drilling operation. In addition, in the data processing unit 126, the generated look-ahead signal can be used to determine formation properties in front of the drill bit. The look-ahead signal and / or certain properties of the formation in front of the drill bit can be used to make a decision on geosteering. Geosteering is a targeted control for correcting the direction of drilling.

Methods for determining the look-ahead signal and / or formation properties in front of the drill bit may include various applications of inversion, direct modeling, the use of synthetic logs and filtering methods. Inversion operations may include comparing measurements with predictions from the model, as a result of which the value or spatial variation of the physical property can be determined. A conventional inversion operation may include determining the variation in electrical conductivity in the formation based on measurements of induced electric and magnetic fields. Other methods, such as direct modeling, deal with calculating expected observed values depending on the intended model. A synthetic well log is a well log modeled on the basis of a simulated response of a tool with known formation parameters. A synthetic well log is formed by numerical modeling of the interaction of the instrument and the formation, usually with the inclusion of modeling for each depth on the log from point to point.

The data processing unit 126 may be adapted to perform data alignment operations on one or more shallow depth measurements, depending on geometric factors with respect to the data of one or more deep measurements, so that a signal is provided by the difference between the data of one or more deep measurements and the aligned data of one or more shallow depth measurements leading view. Alignment can be implemented by inverse filter. The data processing unit 126 may be adapted to perform an inversion based on signals from one or more shallow measurements and signals from one or more depth measurements and to perform operations to subtract the expected depth signal resulting from the inversion from the measured depth measurement signal to form a signal leading view. The data processing unit 126 may be adapted to perform inversion based on signals from one or more shallow measurements without input data from one or more deep measurements and to perform operations to subtract the signal resulting from the inversion used in direct modeling of the deep configuration to generate a signal leading view. Data obtained from selectable transmitter-receiver antenna pairs in data processing unit 126 can be used to substantially suppress signals from the layers between the transmitter antenna and the receive antenna of the respective transmitter-receiver pair in response to the operation of the transmitter antenna. The data obtained from the antenna pairs of the emitter-receiver in the data processing unit 126 can be used without suppressing the signals from the layers.

The emitters and receivers 110-1, 110-2, ..., 110- (N-1), 110-N of the device 105 can be arranged in multiple shared antennas with different angles of inclination. The processing circuits and devices executing the instructions in the control unit 120 and the data processing unit 126 can perform operations of artificially generating tilt angles by combining signals from shared multiple antennas with different tilt angles. Such a scheme allows algorithmically optimizing signal suppression in the device 100 for various dip angles. The processing circuits and devices executing the instructions in the processing unit 120 and the data processing unit 126 can perform artificially creating tilt angles by combining signals from shared multiple antennas to artificially tilt tones to suppress signals from layers between multiple shared antennas. Optimized signal suppression can be used to get a look-ahead signal and evaluate formation properties in front of the drill bit.

The emitters and receivers 110-1, 110-2, ..., 110- (N-1), 110-N of the device 105 can be arranged in a set of emitters and receivers having selected tilt angles, so that signals from layers outside can be suppressed areas between the respective emitters and receivers from this set. This provides suppression opposite to the suppression of the signal from the layer between the emitter and the corresponding receiver, discussed earlier. This gives a shallow readout, which is centered around the device and which can be used instead of the other shallow measurements mentioned in this application. The radiating antenna and the receiving antenna can be located along the longitudinal axis of the device 105, so that at least one of the radiating antenna and the receiving antenna can have an angle of inclination relative to the longitudinal axis of the device, while the orientations of the radiating antenna and the receiving antenna relative to the longitudinal axis and relative to each other Operational suppression of signals from layers outside the region between the respective emitter and receiver will be provided. The processing circuits and devices executing the instructions in the control unit 120 and the data processing unit 126 can perform artificially forming tilt angles by combining signals from multiple shared antennas to suppress signals from layers outside the area between the multiple shared antennas. In applications in which signals associated with the tilt angles of the emitter and receiver are artificially generated from shared antennas with different tilt angles, the same pair of emitter and receiver can be used to focus forward and focus around the device 105.

The control unit 120 and / or the data processing unit 126 can be located on the surface of the well 102 in operative communication with the device 105 through a communication mechanism. Such a communication mechanism can be implemented as a connected vehicle, which is standard in downhole operations. The control unit 120 and / or the data processing unit 126 can be distributed along the mechanism, and the device 105 is placed in the well 102. The control unit 120 and / or the data processing unit 126 can be combined with the device 105 so that the control unit 120 and / or the data processing unit 126 worked in the well 102. The control unit 120 and / or the data processing unit 126 can be distributed along the device 105. Such embodiments, if there is a geosteering mechanism, can provide stable and in-depth assessment of formations through which the drill bit has not yet passed mja drilling operation, preventing dangerous situations, such as emissions and increased selection hydrocarbons.

The device 100 may be adapted to implement a borehole measurement system (BIP), such as a borehole logging system (BHC), in a wellbore. The device 105 can be positioned on a drill bit designed to perform a drilling operation. Alternatively, tool 100 may be suspended from a wireline.

In FIG. 2 shows the actions in the method according to an example of an embodiment for looking ahead in the case of using a bit for a drilling operation. At step 210, the activation of the device located in the well is controlled, while the device has an arrangement of spaced emitting antennas and receiving antennas capable of operating selected emitter-receiver pairs. Controlling the activation of a device may include selecting a transmitter-receiver antenna pair operation such that signals from the layers between the transmitter antenna and the receiver antenna of the respective transmitter-receiver pair are substantially suppressed in response to the radiation of the probe signal by the transmitter antenna. The transmitter-receiver antenna pairs can operate in a mode in which signals from the layers between the transmitter antenna and the receiving antenna of the respective transmitter-receiver pair are not suppressed with respect to the probe signal from the transmitter.

At step 220, a depth signal from a depth measurement is recorded using a transmitter-receiver pair and one or more shallow signals from one or more shallow measurements using one or more other transmitter-receiver pairs. In situations when there is no suppression of signals from the layers during operation of the emitter, numerous shallow measurements can be performed.

At step 230, one or more shallow signals are processed, and a model signal is generated for regions adjacent to the sides and the back of the device. At step 240, the look-ahead signal with substantially no contributions from areas adjacent to the instrument is generated by processing the depth signal depending on the model signal.

Processing one or more shallow signals and generating a look-ahead signal may include aligning one or more shallow signals depending on geometric factors with respect to the depth signal, so that the look-ahead signal is provided by the difference between the depth signal and the aligned one or more signals. Aligning one or more shallow depth measurements may include the formation of a parallel transfer filter from shallow to deep depth by deconvolution of shallow geometric factors and deep geometric factors. Processing one or more shallow signals may include performing an inversion based on one or more shallow signals and deep signals, so that as a result of the inversion, the model signal is obtained as the expected deep signal. Therefore, generating the look-ahead signal may include subtracting the model signal from the depth signal to form the look-ahead signal. Processing one or more shallow signals may include performing an inversion based on one or more shallow signals without input from the deep signal, and applying the resulting inversion signal to directly simulate the deep configuration to obtain a model signal. Therefore, generating the look-ahead signal may include subtracting the model signal from the depth signal to form the look-ahead signal.

According to various embodiments, the inversion can be performed using the look-ahead signal and the parameters of the layers around the device in order to obtain resistivities and positions of the deep layers in front of the drill bit corresponding to the device. The look-ahead signal can be analyzed in the well during the drilling operation and the decision on geosteering can be made in the well based on the analysis. Alternatively, the decision on geosteering may be made on the surface after considering the analysis or performing analysis on the surface. Actions on the surface can be performed through a user interface that works with the display on which the analysis or parts of the analysis are presented to the operator. The resistivities and positions of the deep layers can be obtained as the drill bit moves forward. The drilling operation can be suspended based on the determination that changes in resistivity as the drill bit moves forward exceed the threshold for changing resistivity. Exceeding the threshold value may indicate dangerous pressure changes in front of the bit.

As a rule, all commercially available electromagnetic devices are very sensitive to the properties of the formation that are present in the area between the positions of the emitter and receiver. However, in some applications it may be desirable to have a higher sensitivity above or below this area. For example, such sensitivity may be desirable in geosteering. In geosteering, measurements can be taken in the vicinity of the drill bit during drilling in order to efficiently direct the path of the well to productive zones or to stop drilling before entering the hazardous zone. Although several attempts have been made to create devices that are sensitive to the properties of the formation in front of the bit, in almost all cases, these devices remained more sensitive to the properties of the formation on the side of the device. As a result, measurements are complicated by variations in the formation profile around the device.

In various embodiments, it is possible to implement a process of eliminating effects around the instrument and providing focus in front of the bit. This process can be performed using a certain combination of the angle of inclination of the emitter and the angle of inclination of the receiver to suppress signals from the layers that are between the emitter and the receiver, and the manufacture of the device is not sensitive to the properties of the area on the side of the device. See, for example, FIG. 4A and 4B. The resulting sensitive areas are shown in the left frame in FIG. 3A, while in general in FIG. 3A shows a leading measurement at tilt angles that suppress signals from the layers. As a second procedure, a single shallow measurement can be aligned, depending on the geometric factor, with respect to the first measurement using the inverse filter and then subtracted from the first measurement. See, for example, the middle and right frames in FIG. 3A. However, it is noticeable that the process shown in FIG. 3A may be important for evaluating a drilling operation if shallow measurements are not subtracted. Alternatively, subtraction at arbitrary tilt angles without suppressing the signal from the layer can be used in the process, as shown in FIG. 3B, which shows a leading measurement at arbitrary tilt angles.

It was previously revealed that with a certain combination of the tilt angles of the emitter and the receiver of the device, it is possible to suppress the direct signal from the emitter to the receiver of the device. According to an exemplary embodiment, in another approach, signals that are caused by formation layers between the emitter and the receiver are suppressed. It should be noted that although this certain combination of tilt angles does not lead to a decrease in sensitivity when considering individual points in three-dimensional space, it leads to a decrease in sensitivity at planar boundaries for a given incidence and strike due to the effects of suppressing signals from the layers along the surfaces shown in FIG. 4A and 4B. In FIG. 4A shows an example of effects of suppressing signals from layers in the presence of a boundary between the emitter and the receiver. In FIG. 4B shows an example of effects of suppressing signals from layers in the presence of a boundary outside the area of the emitter-receiver. As a result, an embodiment of an example process may be limited to planar surfaces with known dip and strike angles. It can be seen that even if the surfaces are not perfectly planar or the fall and strike are not exactly known, using the processes discussed in this application, you can still get a good suppression.

In FIG. 5A and 5B show the combined geometric factors for the instrument. These factors are presented for a device with one emitter, one receiver, operating at a frequency of f = 500 Hz, with a separation of d ₁ = 24 feet (7.3 m), in the region of high resistivity. In FIG. 5A shows the combined (in the radial direction) geometrical factors obtained by forming a synthetic log of a very thin low-contrast layer at a zero angle of incidence. Curve 561 is presented for a transmitter tilt angle of 0 ° and a receiver tilt angle of 45 °. Curve 562 is presented for a transmitter angle of 45 ° and a receiver angle of 45 °. Curve 563 is shown for a transmitter tilt angle of 50 ° and a receiver tilt angle of 50 °. Curve 564 is presented for a transmitter tilt angle of 55 ° and a receiver tilt angle of 55 °. From FIG. 5A, it can be seen that at an inclination angle of the emitter and receiver of 55 °, the geometric factor decreases for all positions between the emitter and receiver. It should be noted that although in these cases the slopes of the emitter and receiver are chosen equal, the suppression of signals from the layers can be obtained at different angles of inclination of the emitter and receiver. In FIG. 5B shows a similar plot, but for a dip angle of 30 °. Curve 571 is presented for a transmitter tilt angle of 0 ° and a receiver tilt angle of 45 °. Curve 572 is presented for the angle of inclination of the emitter 45 ° and the angle of inclination of the receiver 45 °. Curve 573 is shown for a transmitter angle of 50 ° and a receiver angle of 50 °. Curve 574 is presented for a transmitter tilt angle of 55 ° and a receiver tilt angle of 55 °. In this case, signal suppression from the layers can still be obtained, but as shown by curve 572, at a different angle, approximately 45 °. Even with a non-optimal tilt angle of 55 °, relatively good suppression can be obtained. As a result, a device with a tilt angle of 45 or 55 ° is considered effective in the range of incidence angles of 0-30 ° at the frequencies and spacings used. This methodology can be used to create instruments that are optimal for different ranges of incidence angles. In addition, it is important to note that a similar optimization process can be used to obtain reverse suppression: a signal outside the region between the emitter and receiver can be suppressed by adjusting the tilt angles of the emitter and receiver, respectively. This gives a shallow readout from the area centered around the device, and it can be used instead of any shallow measurement mentioned in this application. One way to obtain such a configuration is to first use the configuration in accordance with curve 561 and reduce the angle of inclination of the emitter and receiver until the sensitivity relative to the region between the emitter and receiver becomes significantly greater when compared with a signal outside this region. In the case where the signals associated with the tilt angles of the emitter and receiver are artificially generated from shared antennas with different tilt angles, the same pair of emitter and receiver can be used to focus forward and focus around.

In FIG. Figure 6 shows combinations of tilt angles at which the effect of suppressing signals from the layers is achieved, while the dip strike angle is aligned with the dipoles. The distance between the transmitting antenna and the receiving antenna is 24 feet (7.3 m) when operating at 500 Hz in an area with high resistivity. Curve 681 is presented for an angle of incidence of 30 °. Curve 682 is presented for an angle of incidence of 15 °. Curve 683 is presented for an angle of incidence of 30 °. Curve 684 is presented for an angle of incidence of 45 °. Curve 686 is presented for an angle of incidence of 60 °. Curve 681 is presented for an angle of incidence of 75 °. From FIG. 6, it can be seen that the suppression method works up to approximately 60 ° in a wide range of angle combinations for the configuration used. Numerous emitters and receivers can be combined to obtain a suppression effect over a wider range. A device with crossed dipoles or a three-plane device can be used to synthesize dipole vectors at various tilt angles in order to optimally suppress signals from the layers.

In FIG. 7 shows the combined geometric factors for a highly conductive medium. These factors are presented for a device with one emitter, one receiver, operating at a frequency of f = 500 Hz with a spacing of d _l = 24 feet (7.3 m), with an angle of _dip θ = 30 ° of incidence in the region with a resistance of R = 1 Ohm . Curve 771 is presented for a transmitter tilt angle of 0 ° and a receiver tilt angle of 45 °. Curve 772 is presented for a transmitter angle of 44.5 ° and a receiver angle of 44.5 °. Curve 773 is presented for the angle of inclination of the emitter 42.5 ° and the angle of inclination of the receiver 42.5 °. Curve 774 is presented for a transmitter angle of 40.5 ° and a receiver angle of 40.5 °. Although in a high resistivity medium, very good suppression can be obtained at any angle of incidence, but, as shown in FIG. 7, in a medium with a high conductivity, a decrease in the suppression characteristic is observed. In this case, as shown by curve 773, the optimum characteristic is obtained at 42.5 °. Operation at lower frequencies allows for successful suppression at higher conductivities.

In FIG. 8 shows the geometric factors associated with two different spacings. In FIG. 8 also shows the subtraction of geometric factors associated with two different spacings. These factors are presented for a device operating at a frequency of f = 500 Hz in a region with a high resistivity at an angle θ _dip = 0 ° of incidence, with a separation of d _l = 24 feet (7.3 m), while there is a signal shown by curve 891 and a spacing d _l = 20 feet (6 m), and there is a signal shown by curve 892. Curve 893 shows the result of subtracting geometric factors with a spacing of 24 feet (7.3 m) from geometric factors with a spacing of 20 feet (6 m) . From FIG. Figure 8 shows that when using subtraction, the geometric factor can be minimized near the back of the device and focused forward. The signals considered in this application are presented in the values of the millisense. Such signals can be obtained by multiplying the voltages by the corresponding instrument coefficients using well-known procedures.

In FIG. 9A-9C show three embodiments of configurations for suppressing signals from layers and corresponding sensitivity areas. The absolute measurement of FIG. 9A is related to the relative measurement of FIG. 9B and with the compensated measurement of FIG. 9C. By making the relative measurement of FIG. 9B, the need to calibrate the emitter can be eliminated since any multiplicative effect on the emitter signal is suppressed. To suppress the tilt angles of the first and second receivers can be set different. Simultaneous suppression can be obtained at both receivers. When performing the compensated measurement of FIG. 9C, the calibration requirements for emitters and receivers can be further reduced, and multiplicative temperature variations at receivers can also be eliminated. Suppression can be obtained simultaneously on both receivers with two emitters, especially when the distance between the antennas at the front of the device and at the rear of the device is kept small. In various embodiments, one of the antennas can be placed as close to the bit as possible to increase the detection depth in front of the bit.

In FIG. 10A and 10B show examples of deep measurement and shallow measurement configurations. In general, only four antennas can be used: a transmitter and receiver for shallow measurements and a transmitter and receiver for depth measurements. However, as shown in FIG. 10A, a common emitter or receiver can be used to reduce the number of antenna elements. The deep measurement has a sensitivity that continues further than with a shallow measurement, and when drilling signals are received earlier than with a shallow measurement. In depth measurement, there is usually a greater distance between the emitter and receiver than in shallow measurement, but this is not absolutely necessary. With the same antenna pair, the emitter-receiver low operating frequencies can provide greater research distances than high frequencies. The typical distance between the transmitter and receiver in depth measurement is 20-100 feet (6-30.5 m), while the distance between the transmitter and receiver in shallow measurement is from 2 feet (0.6 m) to 20 feet (6 m) . Small-water spacing may be large enough to compensate for the effects of the wellbore and fluid intrusion. To ensure optimal focusing, a shallow measurement should be carried out as close to the drill bit as possible. Sensitivity during depth measurement increases with increasing inclination angles of the emitter and receiver, however, the effects of the wellbore and mandrel also increase. At least one of the emitter and receiver can be tilted to obtain azimuthal sensitivity. Azimuthal sensitivity is important for the application of geosteering, because it allows you to determine the difference between signals coming from different directions. Typical frequency ranges of shallow and deep measurements include 500 Hz - 10 MHz and 50 Hz - 100 kHz, respectively. Numerous frequencies can be used to distinguish between distances to different depth layers. In FIG. 10B shows that the configuration of an existing instrument, such as a commercially available instrument, can be used for shallow or in-depth measurements. Such a device can be implemented using an azimuthal depth resistivity sensor (ADGS).

An azimuthal depth resistivity sensor with oblique antennas in the azimuthal array can be used to obtain measurements in a number of discrete directions called resolution elements or directional resolution elements, which makes it possible to determine the distance to multiple formation boundaries for a number of different exploration depths. For example, an azimuthal depth resistivity sensor can be positioned together with emitters and receivers to use 32 discrete directions and 14 different study depths. However, in an azimuthal depth resistivity sensor, more or less than 32 discrete directions and / or more or less than 14 different study depths can be used. The azimuthal depth resistivity sensor can add dimensionality to measurements when using inclined receiving antennas and repeatedly recording data at each revolution of the device (in accordance with the number of resolution elements), at all possible distances between the emitter and receiver. The tilt of the receivers gives directional sensitivity to a group of azimuthal depth resistivity sensors. Counts from a greater depth, provided by the azimuthal depth resistivity sensor, shorten the period of time before the response, which allows to increase the drilling speed. The azimuthal depth resistivity sensor can provide fully compensated measurements of resistivity of petrophysical quality and depth readouts for geosteering performed in one instrument to minimize the length of the bottom of the drill string (BHA). Azimuthal readings provide anisotropic resistivity, R _h (horizontal) and R _v (vertical), and dip values.

In FIG. 11 shows for comparison periodic differential measurement and measurement with suppression of signals from the layers. In this example, the measurement with suppression of signals from the layers was performed at an emitter tilt angle and a receiver tilt angle of 55 ° when operating at 500 Hz in a region with high resistivity, while the measurement signal is represented by curve 1142. In this example, a periodic differential measurement was performed at an emitter tilt angle of 0 ° and a receiver angle of 45 °, and the differential signal is represented by curve 1141. A periodic differential measurement can be obtained by calculating by subtracting the signal received at one position of the instrument, from a signal received at another position of the instrument 0.2 inches (5 mm) apart. From FIG. 11 it can be seen that the measurement with suppression of signals from the layers can be focused much deeper due to a second-order decay depending on the depth compared to a third-order decay in a periodic differential measurement.

In FIG. 12 is a block diagram of a device 1200 according to an embodiment, such as a data recording system, having a device 1205 with radiating antennas 1210-T-1, ..., 1210-TN and receiving antennas 1210-R-1, ..., 1210-RM operating in the borehole in which the device 1205 is located. Radiating antennas 1210-T-1, ..., 1210-TN and receiving antennas 1210-R-1, ..., 1210-RM can be located along the device 1005, while each can have a tilt angle relative to the longitudinal axis 1207 of device 1205. Radiating antennas and receiving antennas may have a tilt angle of zero degrees. The radiating antenna and the receiving antenna, in at least one combination, can be made with such angles at which the radiating antenna and the receiving antenna of the combination are able to suppress signals from the layers that are between the radiating antenna and the receiving antenna of the combination, and make the device 1205 is not sensitive to the properties of the area on the side of the device 1205, when the device 1205 in the working state is located in the well. The angles of inclination of the emitting antenna and the receiving antenna from the combination may be different. The radiating antenna and the receiving antenna, in at least one combination, can be made with such angles at which the radiating antenna and the receiving antenna of the combination are capable of suppressing signals from layers that are outside the area between the radiating antenna and the receiving antenna of the combination, when the device 1205 in working condition is located in the well. The angles of inclination of the emitting antenna and the receiving antenna from the combination may be different. Radiating antennas 1210-T-1, ..., 1210-TN and receiving antennas 1210-R-1, ..., 1210-RM can include the arrangement of antennas with different angles of inclination, while one or more of the angles of artificially create signal suppression realize artificially. Artificial cancellation can be implemented for signals between shared antennas or for signals from layers outside the area between shared multiple antennas.

The device 1200 may include a system control center 1220, emitters 1212-1, ..., 1210-N, receivers 1214-1, ..., 1214-M, a data recording unit 1222, a data buffer 1224, a data processing unit 1226 and a communication unit 1228 in addition to a device 1205 with radiating antennas 1210-T-1, ..., 1210-TN and receiving antennas 1210R-R-1, ..., 1210-RM. The system control center 1220 may include a central processing unit (CPU), analog electronics, digital electronics, or various combinations thereof to control the operation of other units of the device 1200. The system control unit 1220 may generate a signal and provide a signal to the emitters 1212-1, ..., 1212-N. The signal can be formed in the frequency range from 10 Hz to 10 MHz. Other frequency ranges may be used. Emitters 1212-1, ..., 1212-N can direct currents to radiating antennas 1210-T-1, ..., 1210-T-N, which emit electromagnetic waves into the formation. Although the 1205 is capable of suppressing signals from the layers that are between the emitting antennas and the receiving antennas of the selected combination, which makes the 1205 insensitive to the properties of the area on the side of the 1205, numerous radiating antennas can be used to collect additional data to improve formation definition . For example, using radiating antennas located at different distances from the receiving antennas, it is possible to obtain images from various depths and with different resolutions. As another example, antennas with different angles or orientations can be used to create sensitivity to anisotropic formation parameters.

One or more of the N radiating antennas may be excited by a signal generated by the system control center 1220. For frequency domain applications, the signal may consist of a sine wave at a given frequency. For time domain applications, the signal may be a pulse with a specific shape and frequency spectrum. The emitters can be excited simultaneously or sequentially and the excitation can be maintained for a time sufficient to attenuate transients and attenuate the effect of noise by summing. The received signals can be converted into a region in which the incoming part of the signal can be separated from the reflected part. One specific example of such a transformation is the Hilbert transform. Signals from the receivers are transmitted to the system control center 1220, which can store them in the data buffer 1224 until they are ultimately transmitted to the surface. In addition, the system control center 1220 can control or interact with the geosteering operation essentially autonomously without consulting the ground service, so decisions can be made with minimal delay.

The electromagnetic wave signals that are received at the receiving antennas 1210-R-1, ..., 1210-R-M can be sent to the respective receivers 1214-1, ..., 1214-M and to the system control center 1220. To make better use of time, the operation of device 1200 may include emitting and receiving multiple frequencies at the same time. In such an operation, a sine wave signal, a square wave signal, or other temporary wave signals can be used to simultaneously excite at multiple frequencies each of the emitting antennas 1210-T-1, ..., 1210-T-M or at the individual frequencies of the emitting antennas 1210-T- 1, ..., 1210-TM. Received signals corresponding to multiple frequencies can be separated by filters at the receiving end in block 1222 data recording. The signals from each radiating antenna 1210-T-1, ..., 1210-T-M, received at all receivers 1214-1, ..., 1214-M, can be recorded. To store received signals for subsequent processing, a data buffer 1224 may be used.

A data processing unit 1226 may be used to perform inversion or other data processing. Processing and inversion can be performed in accordance with processing operations similar to or similar to the operations set forth in this application in the embodiments. Inversion operations may include comparing measurements with predictions from the model, so that the value or spatial variation of the physical property can be determined. A conventional inversion operation may include determining the variation in electrical conductivity in the formation based on measurements of induced electric and magnetic fields. Other methods, such as direct modeling, deal with calculating expected observed values depending on the intended model. In various embodiments, the inversion process performed on the data of device 1200 may be performed in a well or in an analysis unit, such as a computer, on surface 1204 after data has been transmitted to surface 1204. Communication unit 1228 may transmit data or results to surface 1204 for study and / or determining the subsequent action required when performing the drilling operation associated with the measurements obtained using the device 1200. In addition, data or results can be transferred to each other m devices in the well and used to improve various aspects of locating and extracting hydrocarbons.

In the presence of the obtained data of shallow and deep measurements, it is possible to invert complete enumeration relative to the set of obtained measurements. However, instead of this, advanced processing can be obtained using the procedure for dividing the entire operation into two parts: calculating the look-ahead signal and calculating the properties of the reservoir layer based on the look-ahead signal. These two parts of the method make it possible to obtain interpretations directly on the basis of the look-ahead signal, even if the solutions for horizontal resistivity R _{h of the} deep layer, vertical resistivity R _v and position are not unique. In FIG. 13 shows the steps of a method for calculating a look-ahead signal by inverting shallow and depth measurements according to an example embodiment. In this calculation, you can use the full inversion using a shallow signal 1311 and a deep signal 1312. A shallow signal 1311 and a deep signal 1312 can be represented by a numerical inversion 1331. With a numerical inversion 1331, a number of different conventional methods can be used, including, but not limited to them, image matching and iterative methods. Library 1332 and direct model 1333 can facilitate numerical inversion 1331. Inverted wellbore parameters after correction 1334 for well influence can be fed back to numerical inversion 1331 to obtain better estimates. The output of numerical inversion 1331 may include resistivity (R _h , R _v ) of the layers, position (z) of the layers, dip angle (θ), strike angle (ϕ), borehole radius (r _b ), resistivity (R _b ) borehole walls, eccentricity (d _ecc ) and azimuth (ϕ _ecc ) of eccentricity. To update the well influence correction 1334, these parameters can be transferred back to the well influence correction circuit 1334. In addition, these factors can be fed forward to obtain data for layers around or behind instrument 1335 for further processing. The resistivities (R _h , R _v ) of the deep layers, the positions (z) of the deep layers, obtained as a result of numerical inversion 1331, are not intended to determine the look-ahead signal, these data are stored for further processing together with the measured deep signal 1312 associated with layers around or behind the appliance. Data for the layers around or behind the device 1335 can be submitted to direct modeling 1336 to obtain a depth configuration correlated with the layers around or behind the device. The direct modeling output 1336 provides a model signal representing the expected depth signal from the layers around the device, which can be directed to the subtraction unit 1337. The look-ahead signal can be obtained by subtracting the expected depth signal from the layers around the instrument from the measured depth signal.

In FIG. 14 shows the steps of a method for calculating a look-ahead signal according to an example embodiment where only a shallow signal 1411 is used. In this case, all layers near the device are inverted layers, since a shallow measurement is most sensitive near the device. A shallow signal 1411 can be represented by numerical inversion 1431. When numerically inverting 1431, a number of different conventional methods can be used, including, but not limited to, image matching and iterative methods. Library 1432 and direct model 1433 can facilitate numerical inversion 1431. Inverted parameters of the wellbore after correction 1434 for the influence of the well can be fed back to numerical inversion 1431 to obtain better estimates. The output of numerical inversion 1431 may include resistivity (R _h , R _v ) of the layers, position (z) of the layers, dip angle (θ), strike angle (ϕ), borehole radius (r _b ), resistivity (R _b ) borehole walls, eccentricity (d _ecc ) and azimuth (ϕ _ecc ) of eccentricity. In order to update the well influence correction 1434, these parameters can be transferred back to the well influence correction circuit 1434. In addition, these factors can be applied to direct simulation 1436 using a deep configuration to obtain a signal that spans layers only near the instrument. The direct modeling output 1436 provides a model signal covering layers only in the vicinity of the device, which can be directed to the subtraction unit 1437. As a result, by subtracting the model signal from the measured deep signal 1412, a look-ahead signal can be obtained.

In FIG. 15 shows an example of an embodiment of computing a look-ahead signal using deconvolution. Such calculation of the look-ahead signal can be performed in a manner that does not include inversion. In this case, direct modeling 1541 can be performed to obtain shallow geometric factors 1542 as a function of depth associated with deep configurations. Direct modeling 1543 can be performed to obtain deep geometric factors 1544 as a function of depth associated with shallow configurations. Formation fall can be introduced into direct modeling 1541 and direct modeling 1543. One way to obtain a geometric factor is to construct a synthetic log of the formation, which includes background resistivity and a very thin layer at zero depth. The background resistivity is assumed to be sufficiently large compared to the reciprocal of the frequency, in which case a slight skin effect is observed. In addition, it is expected that the method shown in FIG. 15, will work in the presence of significant skin effects, but in this case, the method should use special geometric factors, calculated taking into account the specific resistivity. However, the resulting look-ahead signal may be contaminated by a shallow signal due to the non-linearity induced by the skin effect.

After calculating the geometric factors, the filter is calculated by deconvolution of the shallow geometric factor based on the deep geometric factor 1545. For geosteering applications, future signal values are not available, so the filter can be converted to a causal filter, for example, by setting zero values on the future side of the filter and adding the sum of the deleted values to the last available filter coefficient. In situations where the dipole orientations of the emitter and receiver are not optimal (for example, if they do not provide good suppression of signals from the layers), the emitter and receiver can be rotated to any angle, provided that measurements with crossed dipoles can be performed to optimize the 1552 dipole orientation for the deep signal 1512 and to optimize the 1554 dipole orientation for the shallow signal 1511. In situations where the emitting or receiving antennas rotate, the resulting dipole orientations p Different antennas can be combined for similar optimization.

By applying a 1556 filter to a shallow signal, its resolution and centering are aligned with respect to the depth measurement, obtaining a parallel transferred shallow signal 1157. This ensures effective subtraction of the shallow signal from the deep signal in the subtraction unit 1537 without creating effects due to the difference in resolutions. In addition, the correction procedure 1555 for influencing the depth of the skin effect and the well for a shallow signal 1511 and the correction procedure 1553 for influencing the depth of the skin effect and the well for the deep signal 1512 can be applied before subtraction and filtering in order to reduce and therefore equalize the effects of depth skin effects and wells. There is no inversion in the above methodology and it can work even in situations where it is assumed that the inversion will not work well enough. With this methodology, processing can be very fast and the methodology can be used for geosteering, since the greatest computational cost is the use of the filter.

In FIG. 16 shows an example embodiment of calculating the properties of deep layers by complete inversion. Although the lead signal itself is useful for applications, it may be desirable to calculate the resistivity and the positions of the layers in front of the bit. This can be done using an inversion algorithm in which, as shown in FIG. 16, all known information, such as layer parameters around the device, is taken into account. The look-ahead signal can be presented for inversion 1631 together with parameters near the device, such as resistivities (R _h , R _v ) of the layers, position (z) of the layers, angle (θ) of incidence, angle (ϕ) of strike, radius (r _b ) the borehole, the resistivity (R _b ) of the borehole wall, eccentricity (d _ecc ) and azimuth (ϕ _ecc ) of eccentricity. Library 1632 and direct model 1633 may facilitate inversion 1631. Inversion 1631 may include the use of one or more methods, such as, but not limited to, analytical formulas, pattern matching, and iterative methods to obtain resistivities (R _h , R _v ) deep layers and the positions (z) of the deep layers.

In FIG. 17 shows an example embodiment of calculating the properties of deep layers using a simple inversion. In cases where only the incidence angle (θ) and the strike angle (ϕ) are known, then, as shown in FIG. 17, the change in resistivity and the position of the layer can be obtained by inversion. The look-ahead signal can be represented by inversion 1731 together with the angle of incidence (θ) and the angle of rotation (ϕ). Library 1732 and direct model 1733 may facilitate inversion 1731. Inversion 1731 may include the use of one or more methods, such as, but not limited to, analytical formulas, pattern matching, and iterative methods to obtain resistivities (R _h , R _v ) deep layers and the positions (z) of the deep layers. Since the geometric factor is inversely proportional to the square of the distance to the layer boundary, analytical formulas can be used for inversion. Since large changes in resistivity may indicate large changes in pressure, the results of this calculation, for safety's sake, can be used to stop drilling before approaching hazardous areas.

In FIG. 18 shows an example of an embodiment of calculating the properties of deep layers using inversion. The calculation method shown in FIG. 18 can be used to reverse the distance to the layers and the resistivity of the layers. The calculation can begin by applying the angle of incidence (θ) and the angle of rotation (ϕ) to direct modeling 1833. If the depth of the skin effect is sufficiently small or it can be sufficiently compensated, then an approximately linear relationship between the conductivity of each layer will be observed and the signal that is formed at the receivers. As a result, for a given signal, due to a small perturbation of the conductivity distribution, it can be predicted what the contribution of the signal from the layer with any conductivity will be. For this, at step 1831, based on direct modeling 1833, a step response U ⁿ (d) can be formed by artificial logging of a two-layer formation in the case when only a very small contrast Δσ exists between the specific conductivities of the layers. At step 1832, the full signal in the n-th measurement at depth z in the case of a perturbation of a single layer can be written based on the linearity property

, $$$$

(1) $${\sigma }^n(z)={\sigma }_{background}^n+{\sigma }_{contrast}^n{U}^n(d)$$

, $$$$

(one)

where σ _contrast is the difference between the specific conductivities of the layer in which the device is located and the layer in front of the device, and σ _background is the specific conductivity of the layer in which the device is located. At step 1834, to eliminate the effect of an unknown background, a difference signal can be calculated

(2)DSM ⁿ (σ _contrast , d) = σ _contrast (U ⁿ (d) -U ⁿ (d-Δz)). $$$$

(2)

At step 1835, the influence of the conductivity contrast can be eliminated by taking into account the ratio of differential signals from the nth and mth measurements

. $$$$

(3) $$RDS{M}^{nm}(d)=\frac{DS{M}^n(d)}{DS{M}^m(d)}$$

. $$$$

(3)

At step 1836, the look-ahead signal σ ⁿ (z) for the n-th measurement at depth z can be presented to calculate the differential signal DS ⁿ (z) = (σ ⁿ (z) -σ ⁿ (z-σz)). At step 1837, the ratio of the differential signals can be calculated using the result from step 1836 in the form of RDS ^nm (z) = DS ⁿ (z) / DS ^m (z). As shown in FIG. 16, at step 1838, the differential signal obtained from the measurements can be reversed with respect to the distance d ^nm (z) and the conductivity σ ⁿ _contrast (z) of the layers in front of the device when using the relations from equations 1-3. The distance d ^nm (z) can be found from the condition RDS ^nm (z) = RDSM ^nm (d). The specific conductivity σ ⁿ _contrast (z) can be found from the condition DS ⁿ (z) = DSM ⁿ (σ ⁿ _contrast , d ^nm (z)). Each estimation with different n and m gives results for a different detection depth, and at step 1839 the optimal measurements can be selected visually or algorithmically. The resistivities (R _h , R _v ) of the deep layers and the positions (z) of the deep layers can be obtained by performing this inversion process. When the device is far from the border, it can be expected that only in-depth measurements will give good results. As the device approaches the measurement boundary from a lower detection depth, they can become reliable. For the processing disclosed in FIG. 18, the layer boundary is required to be within at least two different dimensions. Although depth measurements can be observed at deeper depths, shallow measurements can be more accurate because they are less affected by the boundaries of multiple layers.

According to various embodiments, the execution of the processing schemes set forth in this application can be repeated and new measurements can be added as the device moves and the drilling progresses. In FIG. 19 is a decision chart for geosteering according to an example embodiment. The lead-ahead signal along with the resistivities (R _h , R _v ) of the deep layers and the positions (z) of the deep layers can be presented for visual and / or algorithmic research 1951, based on which a decision can be made on geosteering. Decisions about geosteering can be made by a person who on the surface examines the results of processing measurements. Alternatively, decisions on geosteering can be made in the well by an automated system. An automated system can respond much faster because there are natural delays associated with downhole telemetry when transmitting data to the surface. The look-ahead signal is proportional to the degree of contrast of the resistivity and the distance to the change. As a result, a look-ahead signal can provide a useful measure of the nature of the approaching layers. Since a signal that is very similar to the signal from the near layers with a small contrast of the resistivity is created from the deep layers that are farther away, with high contrast, in some cases it can be difficult to find unambiguous results for the resistivity and distance. In such cases, the look-ahead signal itself can be used to make a decision. Another option is to use a priori information regarding the resistivities of the layers or the distances to them to eliminate the ambiguity of the problem.

Works known from the literature focus on increasing sensitivity in front of the device, and reducing sensitivity around the device is not considered. As a result, existing instruments receive a mixture of signals from areas around and in front of the instrument, which is very difficult or impossible to separate. According to various embodiments, to obtain the effect of suppressing signals from layers between emitters and receivers, certain antenna tilt angles can be used. This essentially eliminates the sensitivity to these layers. In addition, you can use an alternative method in which deconvolution and inversion of numerous spatial data is used to reduce sensitivity to layers that are near the device. The resulting method makes it possible to look ahead in practical scenarios and in the presence of numerous layers with varying resistivities as opposed to known methods that are difficult to perform and complex.

In FIG. 20 shows geometric factors associated with two different distances between the emitter and the receiver. In this example, a 4-foot (1.2 m) distance was used for shallow measurements performed at 15 kHz with an antenna tilt of 45 ° and an antenna tilt of 0 °, while the signal is shown by a curve of 2096. A distance of 24 feet (7.3 m) was used for depth measurements performed at 500 Hz with an antenna tilt of 45 ° and an antenna tilt of 0 °, the signal shown by curve 2097. The instrument offset was defined as the true vertical position of the device along the z axis, where the z axis is directed upwards. From FIG. 20, it can be seen that the depth measurement is more sensitive to depth positions (z> 0). The sensitivity is maximum and constant when the layer boundary is between the emitter and the receiver (-4 <z <0 for shallow measurements and -24 <z <0 for depth measurements). Based on these two curves, an inverse filter with the characteristic shown in FIG. 21, which illustrates a non-causal inverse filter. As shown in FIG. 22, this filter is made causal.

In each of FIG. 23 and FIG. 24 shows a synthetic well log at zero dip angle and four layers in the inversion process. The boundaries of the layers are shown by vertical lines 2304, 2306, and 2308, while the resistivity of each layer is shown in each region. In FIG. 23 shows an emitter operating at 500 Hz with an inclination angle of 45 ° at a distance of 24 feet (7.3 m) to a receiving antenna having an inclination angle of 0 °, and an emitter operating at 15 kHz with an inclination angle of 45 ° at a distance of 4 feet (1.2 m) to the same receiving antenna. Curve 2341 shows the depth signal. Curve 2342 shows a shallow signal. Curve 2343 shows a parallel transferred shallow signal. Curve 2344 shows the lead signal. In FIG. 24 shows an emitter operating at 500 Hz with an inclination angle of 55 °, at a distance of 24 feet (7.3 m) to a receiving antenna having an inclination angle of 55 °, and an emitter operating at 15 kHz with an inclination angle of 55 °, at a distance of 4 feet (1.2 m) to the same receiving antenna. Curve 2441 shows the depth signal. Curve 2442 shows a shallow signal. Curve 2443 shows a parallel transferred shallow signal. Curve 2444 shows the lead signal. The instrument was set to move from z = 200 feet (61 m) to z = -200 feet (-61 m), where the depth was defined as -z. The inversion method shown in FIG. 14 was used in the calculations of the parallel transferred shallow signal and the signal of leading viewing. It can be seen that the look-ahead signal clearly indicates the approaching layers, while a more significant signal is formed with a higher resistivity contrast. As discussed earlier, the distance to the approaching layer and its resistivity can be determined on the basis of inversion when using the profile of the look-ahead curve. Although a single distance provides adequate information in the case of such an inversion, higher accuracy can be obtained by using multiple distances in depth. In FIG. 24 higher signal levels are shown for the case when the emitting and receiving antennas were tilted to suppress signals from the layers and focus to a greater depth.

In FIG. 25 shows the results obtained for the configuration of FIG. 23 using the deconvolution methodology described with respect to FIG. 15. In FIG. 25 shows an emitter operating at 500 Hz with an inclination angle of 45 °, at a distance of 24 feet (7.3 m) to a receiving antenna having an inclination angle of 0 °, and an emitter operating at 15 kHz with an inclination angle of 45 °, at a distance of 4 feet (1.2 m) to the same receiving antenna. Curve 2541 shows the depth signal. Curve 2542 shows a shallow signal. Curve 2543 shows a parallel transferred shallow signal. Curve 2544 shows the lead signal. The results are comparable with the results from the inversion method, but some noise was observed due to causal realization and skin depth effects.

In FIG. 26 and 27 show for comparison the standard configuration and the configuration with the suppression of signals from the layers in relation to the practical case with a large number of layers with some variation in resistivity. In FIG. Figure 26 shows a synthetic log with 2 zones (separated by a section boundary 2604) and 20 layers in comparison with a standard measurement configuration. In FIG. 27 shows a synthetic log with 2 zones (separated by a section boundary 2604) and 20 layers in comparison with the configuration of suppressing signals from the layers. In this example, the resistivity limits in the first zone are between 2.5 and 3.8 Ohm · m, and the resistivity limits in the second zone are between 22 and 27 Ohm · m, and the interface 2604 is between the zones. In both configurations, the same antenna locations are used, but the tilt angles are different. In FIG. 26 shows an antenna having a tilt angle of 45 ° at a distance of 24 feet (7.3 m) to an antenna having a tilt angle of 0 ° operating at 500 Hz, and an antenna having a tilt angle of 45 ° at a distance of 4 feet (1.2 m) ) to another antenna with an angle of 0 ° operating at 15 kHz. In FIG. 27 shows an antenna having a tilt angle of 55 ° at a distance of 24 feet (7.3 m) to an antenna having a tilt angle of 55 ° operating at 500 Hz, and an antenna having a tilt angle of 55 ° at a distance of 4 feet (1.2 m) ) to another antenna with an inclination angle of 0 ° operating at 15 kHz. Curve 2651 shows a deep signal. Curve 2652 shows a shallow signal. Curve 2653 shows a parallel transferred shallow signal. Curve 2654 shows the lead signal. Curve 2751 shows a deep signal. Curve 2752 shows a shallow signal. Curve 2753 shows a parallel transferred shallow signal. Curve 2754 shows the lead signal.

In the configuration with the suppression of signals from the layers, the tilt angles at depth readings, with a typical distance between antennas of 24 feet (7.3 m), were set so that the effect shown in FIG. 3. In the standard configuration, the effect of the boundary becomes significant at a range of about 5 feet (1.5 m) due to the high sensitivity to the layers between the lower and middle antennas. In a layer suppression configuration, the detection depth rises to 15 feet (4.6 m). Another important feature of suppressing signals from layers is that, as shown, for example, in FIG. 9, the deep waveform directly reflects the layers in front and behind the instrument. The influence of the layers behind the instruments is eliminated during the process shown in FIG. 14, and imperceptibly in the look-ahead signal. The plateau observed between depths of 0 and 20 feet (0.6 m) is due to the insensitivity of the instrument to the strata between the middle antenna and the lower antenna. This phenomenon can be eliminated by using a configuration such as that shown in FIG. 23.

In FIG. 28A-C show an example of a step response model and examples of differential signal models. In FIG. 28A shows a step response model; FIG. 28B shows a differential signal model, and FIG. 28C shows a differential signal relationship model. These models can be obtained using the equations associated with figure 16. The device can be used at different distances between the antennas. The multiple distances in FIG. 28-C from four antennas, each with a 55 ° tilt angle, include a distance of 3 feet (0.9 m) for operating at 32000 Hz, 6 feet (1.8 m) for operating at 8000 Hz, 12 feet (3.6 m) for operating at 2000 Hz and 24 feet (7.3 m) for operating at 500 Hz, up to a common antenna with a tilt angle of 55 °. Since the transition to a stepped profile is assumed at z = 0, the removal of the device is equal to the distance to the border at positive values. Curve 2861 shows a stepped response for a distance of 3 feet (0.9 m). Curve 2862 shows a step response for a distance of 6 feet (1.8 m). Curve 2863 shows a stepped response for a distance of 12 feet (3.65 m). Curve 2864 shows a stepped response for a distance of 24 feet (7.3 m). Curve 2871 shows a differential signal for a distance of 3 feet (0.9 m). Curve 2872 shows the differential signal for a distance of 6 feet (1.8 m). Curve 2873 shows the differential signal for a distance of 12 feet (3.65 m). Curve 2874 shows a differential signal for a distance of 24 feet (7.3 m). Curve 2881 shows the ratio of differential signals for a ratio of 3 feet (0.9 m) to 6 feet (1.8 m). Curve 2882 shows the ratio of differential signals for the ratio of the distance of 6 feet (1.8 m) to the distance of 12 feet (3.65 m). Curve 2883 shows the ratio of the differential signals for the ratio of the distance of 12 feet (3.6 m) to the distance of 24 feet (7.3 m). From the graph of differential signals it can be seen that for each value of the differential signal in the considered range, one can find a unique range to the border. Sensitivity to the differential signal decreases with increasing range to the border. Similar observations can be made for the ratio of differential signals.

In FIG. 29, for an example of a case of multiple boundaries and two zones, signals are corrected for the effect of the skin effect. This example shows multiple distances from four antennas, each tilted at an angle of 55 °, a distance of 3 feet (0.9 m) for operating at 32000 Hz, 6 feet (1.8 m) for operating at 8000 Hz, 12 feet (3.65 m) for operating at 2000 Hz, and 24 feet (7.3 m) for operating at 500 Hz, to a common antenna with an angle of inclination of 55 °. Examples of conductivity values are shown in FIG. 29. Curve 2951 shows a signal for a distance of 3 feet (0.9 m). Curve 2952 shows a signal for a distance of 6 feet (1.8 m). Curve 3953 shows a signal for a distance of 12 feet (3.65 m). Curve 2954 shows a signal for a distance of 24 feet (7.3 m).

In FIG. 30A-B for the example of the case of FIG. Figure 29 shows the inverse range to the boundary and the conductivity contrast. This example shows multiple distances from four antennas, each tilted at an angle of 55 °, a distance of 3 feet (0.9 m) for operating at 32000 Hz, 6 feet (1.8 m) for operating at 8000 Hz, 12 feet (3.65 m) for operating at 2000 Hz and 24 feet (7.3 m) for operating at 500 Hz, up to a common antenna with a tilt angle of 55 °. The inverted range to the boundary and the resistivity contrast can be obtained using the algorithm associated with FIG. 18. FIG. 30A of curve 3081 shows a range for a ratio of 3 feet (0.9 m) to 6 feet (1.8 m). Curve 3082 shows the range for the ratio of 6 feet (1.8 m) to 12 feet (3.65 m). Curve 3083 shows the range for the ratio of 12 feet (3.65 m) to 24 feet (7.3 m). In FIG. 30B with an area of 3091 shows the conductivity contrast for a distance of 3 feet (0.9 m). Area 3092 shows the conductivity contrast for a distance of 6 feet (1.8 m). Area 3094 shows the conductivity contrast for a distance of 24 feet (7.3 m). In this case, instead of using the look-ahead signal, the full signals from FIG. 29. This can give good results due to the possibility of suppressing signals from the layers inherent in the measurement at which the signal is focused in front of the device. Despite the fact that there will also be some focus to the back of the device, the sensitivity on the back will not create artifacts if large variations in conductivity are absent on the back of the device when it approaches the zone boundary. In this example, the differential measurement distance was chosen Δz = 2 feet (0.6 m), i.e. large enough to exclude the influence of measurement noise and small enough to have a small measurement depth upon detection. From this figure, it can be seen that in this example, with two measurements at the deepest depths and distances between antennas of 24 feet (7.3 m) and 12 feet (3.65 m), the distance and resistivity can be read away from the boundary approximately 15 feet (4.6 m). The resistivity values obtained on the basis of the algorithm are close to the real contrast of about 300-400 mS. Distance measurements are also close to real values. When using an embodiment of the inversion method set forth in this application, it is possible to successfully determine predetermined parameters even without completely separating the look-ahead signal and in the presence of multiple layers. During additional checks, it was found that if signal suppression from layers is not used, signals from multiple layers will degrade results and inversion will not lead to success.

When the instruments measure the resistivity in front of the bit, they can take measurements of the properties of formations that have not yet been drilled, and this will allow more informed decisions on geosteering to maximize production and reduce the number of dangerous situations, such as drilling at abnormal pressures. Known works are aimed at increasing the sensitivity in front of the device, but they completely do not address the problems associated with sensitivity around the device. It should be expected that with a high sensitivity around the device there will be very great difficulties in detecting a signal in front of the device. According to various embodiments, the devices are capable of substantially completely eliminating sensitivity to electromagnetic waves when taking depth samples from areas located on the sides of the measuring device and focusing in front of the device. Such an arrangement can provide increased sensitivity when measuring compared to devices and methods that exclude a direct signal between the emitter and the associated receiver on the device due to the use of certain tilt angles. With this arrangement, it is possible to significantly increase the positive results provided by the depth sampling device, since one of the greatest risks associated with the physical properties of the sensor is considered to be complications caused by the layers that are around the device. Instruments made and structured to operate according to embodiments similar or identical to the embodiments set forth in this application can be used for geosteering and pore pressure measurements.

The various components of the measuring device and processing unit, which form, as described in this application or similarly, the leading signal and formation properties signals in front of the bit when using shallow measurements and depth measurements, in the presence or absence of an antenna pair of emitter-receiver oriented to suppress or essentially suppressing signals from the layers between the emitting antenna and the receiving antenna in response to the action of the emitter in the well, can be implemented by a combination of hardware and software. These implementations may include computer-readable media having machine-executable instructions, such as computer-readable media, having computer-executable instructions for operating a system for activating control of a device located in a wellbore, the device having an arrangement of emitting antennas and receiving antennas spaced to a distance adapted to work with selectable pairs of emitter-receiver; for recording a deep signal from a deep measurement when using a pair of emitter-receiver and one or more shallow signals from one or more shallow measurements when using one or more other pairs of emitter-receiver; for processing one or more shallow signals, forming a model signal relative to areas adjacent to the sides and the back of the device; and for generating a look-ahead signal substantially without contributions from areas adjacent to the instrument, by processing the depth signal depending on the model signal. The instructions may include instructions for operating an apparatus having multiple emitter-receiver pairs and processing signals from in-depth measurements and shallow-depth measurements, similar or identical to the processing considered in relation to FIG. 1-30A-B. Instructions may include instructions for operating the instrument and geosteering operations according to the ideas set forth in this application. In addition, in this case, the computer-readable storage device is a physical device in which data represented by the physical structure in the device is stored. Examples of computer-readable storage devices include, but are not limited to, read-only memory (ROM), random access memory (RAM), magnetic disk storage, optical memory, flash memory, and other electronic, magnetic and / or optical storage devices.

In FIG. 31 is a block diagram of a system 3100 according to an embodiment including a meter 3105 having an arrangement of emitters and receivers from which it is possible to register measurement signals to obtain in-depth measurements and shallow-depth measurements to generate a look-ahead signal and determine formation properties in front of the drill bit. The layout of the emitters 3110-1 and receivers 31102 of the measuring device 1305 can be implemented similarly or identically to the layouts discussed in this application. The arrangement may include one or more pairs of emitter-receiver, adapted to suppress or essentially suppress signals from the layers between the emitting antenna and the receiving antenna in response to the operation of the emitter in the well.

In addition, system 3100 may include a controller 3141, memory 3142, electronics 3143, and communication unit 3145. The controller 3141, the memory 3142, and the communication unit 3145 can be adapted to control the operation of the measuring device 3105 to determine the leading signal and to determine the properties of the area in front of the measuring device 3105. In the case of the measuring device 1305 attached to the drill string near or above the drill bit, the area in front of the measuring device 1305 is the area in front of the drill bit. A controller 3141, a memory 3142, and electronic equipment 3143 can be adapted to control the activation of the radiating antennas and select the receiving antennas in the measuring device 3105 and to control the processing circuits in accordance with the measuring procedures and signal processing described in this application. Communications unit 3145 may include downhole communications used in a drilling operation. Such downhole communications may include a telemetry system.

In addition, system 3100 may include bus 3147, with bus 3147 providing electrical conductivity between components of system 3100. Bus 3147 may include an address bus, data bus, and control bus, each of which is independently configured. As bus 3147, conventional conductive lines can also be used to transmit one or more of an address, data or control, the use of which can be controlled by controller 3141. Bus 3147 can be configured so that system components 3100 can be distributed. Such a distribution is possible with respect to downhole components, such as emitters and receivers of meter 3105, and components that can be located on the surface of the well. For example, as an option, the components may be co-located on one or more of the drill collars or on the cable-lowered structure.

According to various embodiments, peripheral devices 3146 may include displays, additional memory, and / or other control devices that may operate in conjunction with controller 3141 and / or memory 3142. According to an embodiment, controller 3141 may be implemented as one or more processors. The peripheral devices 3146, together with the display, can be provided with instructions stored in the memory 3142 for implementing a user interface for controlling the operation of the measuring device 3105 and / or components distributed in the system 3100. Such a user interface can work in conjunction with the communication unit 3145 and the bus 3147. The various components of system 3100 can be combined with meter 3105, so that processing identical or similar to the processing described in this application in various embodiments is implemented I, may be performed in the wellbore near the measurement site or on the surface.

In FIG. 32 shows a system 3200 according to an embodiment located on a well site, wherein system 3200 includes a measuring device 3105 having an arrangement of emitters and receivers from which measurement signals can be recorded in depth measurements and shallow measurements to generate a look-ahead signal and determine properties formation in front of the drill bit. The arrangement of emitters and receivers of the measuring device 3105 can be implemented identical or similar layouts discussed in this application. The arrangement may include one or more antenna pairs of the emitter-receiver, adapted to suppress or essentially suppress signals from the layers between the emitting antenna and the receiving antenna in response to the operation of the emitter in the well.

System 3200 may include a drilling rig 3202 located on surface 3204 of well 3206 and a drill string 3208, that is, a drill string connected to each other to form a drill string that is lowered using a rotary table 3207 into a borehole or wellbore 3212 wells. The drilling rig 3202 may support the drill string 3208. The drill string 3208 passing through the rotary table 3207 may be set in motion to drill the wellbore 3212 through the subterranean formations 3214. The drill string 3208 may include a drill pipe 3218 and an assembly 3220 of the bottom of the drill string, located at the bottom of the drill pipe 3218.

The bottom hole assembly 3220 may include a weighted drill pipe 3215, a meter 3205, and a drill bit 3226. In various embodiments, the meter 3205 may include a sensor located as close to the drill bit 3226 as possible. The drill bit 3226 may be driven into action for the formation of the wellbore 3212 by sinking the surface 3204 and underground formations 3214. The measuring device 3205 can be adapted to implement a measurement system in the wellbore during drilling, t Like a logging system while drilling. The measuring device 3205 can be implemented in a housing containing electronics for exciting a radiating source and for collecting responses from selectable receiving sensors. Such electronics may include a processing unit for analyzing the signals collected by the measuring device 3205 and transmitting the processed results to the surface using the standard communication mechanism used in the operation of the well. Alternatively, the electronics may include a communication interface for transmitting the signals detected by the measuring device 3205 to the surface using a standard communication mechanism used in the operation of the well, where the detected signals can be analyzed in the surface processing unit.

According to various embodiments, the measuring device 3205 may be enclosed in a device body 3270 connected to a wireline cable 3274, such as, for example, an armored wireline cable. The instrument housing 3270 comprising the meter 3205 may include electronics for driving a transmitter emitting transducer of the meter 3205 and collecting responses from selectable receiving sensors of the meter 3205. Such electronics may include a processing unit for analyzing the signals collected by the meter 3205, and transmitting the processed results to the surface using the standard communication mechanism used in the operation of the well. Alternatively, the electronics may include a communication interface for transmitting the signals collected by the measuring device 3205 to the surface using the standard communication mechanism used in the operation of the well, while these collected signals are analyzed in the surface processing unit. Logging cable 3274 can be implemented in the form of an armored logging cable (multicore power and communication cables), a single-core cable (single conductor) and / or a steel cable of small diameter (without conductors for power supply or communication) or another design suitable for use in the trunk 1312 wells.

During drilling operations, the drill string 3208 may rotate in the rotary table 3207. In addition to this, or alternatively, the bottom assembly of the drill string 3220 may also be driven by a motor (e.g., a downhole motor) located in the well. Weighted drill pipes 3215 can be used to add weight to drill bit 3226. In addition, weighted drill pipes 3215 can stiffen drill string 3220, which allows drill string 3220 to transfer additional mass of drill bit 3226 and facilitate penetration of drill bit 3226 through the surface. 3204 and 3214 underground formations.

During drilling operations, the mud pump 3232 can pump the flushing fluid (sometimes referred to as drilling fluid specialists) from the sump 3234 through the hose 3236 to the drill pipe 3218 and down to the drill bit 3226. The flushing fluid may leak from the drill bit 3226 and return to the surface 3204 through the annular space 3240 between the drill pipe 3218 and the sides of the wellbore 3212. Then, the flushing fluid may return to a sump 3234, in which such fluid is filtered. In some embodiments, the flushing fluid may be used to cool the drill bit 3226, as well as to lubricate the drill bit 3226 during drilling operations. In addition, flushing fluid can be used to remove cuttings from the subterranean formation 3214 resulting from the operation of drill bit 3226.

Although specific embodiments have been shown and described, those skilled in the art will appreciate that any arrangement that is designed to solve a similar problem can be substituted into the specific embodiments shown. In various embodiments, permutations and / or combinations of the embodiments described herein are used. It should be understood that the above description is intended to be illustrative and not restrictive, and that the phraseology or terminology used in this application serves the purpose of the description. Combinations of the above embodiments and other embodiments will become apparent to those skilled in the art upon examination of the above description.

Claims (31)

1. A method of taking measurements in a well, comprising the steps of:
control the activation of the device located in the well, while the device has a layout of radiating antennas and receiving antennas spaced at a distance capable of working with selectable pairs of emitter-receiver;
registering a deep signal from a deep measurement using a pair of emitter-receiver, and one or more shallow signals from one or more shallow measurements using one or more other pairs of emitter-receiver;
process one or more shallow signals, form a model signal relative to areas adjacent to the sides and the back of the device; and
generate a look-ahead signal essentially without contributions from areas adjacent to the device by processing the depth signal depending on the model signal. 2. The method according to claim 1, in which the activation control of the device includes selecting the operation of the antenna pairs of the emitter-receiver so that signals from the layers between the emitting antenna and the receiving antenna of the corresponding pair of emitter-receiver are essentially suppressed in response to the radiation of the probe signal radiating antenna. 3. The method according to claim 1, wherein processing one or more shallow signals and generating a look-ahead signal includes aligning one or more shallow signals depending on geometric factors with respect to the deep signal so that the difference between the deep signal and the aligned one or several shallow signals provided a leading-viewing signal. 4. The method according to p. 3, in which the alignment of one or more shallow measurements includes the formation of a parallel transfer filter from shallow to great depth by deconvolution of shallow geometric factors and deep geometric factors. 5. The method according to claim 1, in which the processing of one or more shallow signals and generating a look-ahead signal includes performing an inversion based on one or more shallow signals and a deep signal, so that the model signal is obtained as the expected deep signal as a result of the inversion, and subtracting the model signal from the deep signal to form a look-ahead signal. 6. The method according to claim 1, in which the processing of one or more shallow signals and generating a look-ahead signal includes performing an inversion based on one or more shallow signals without input from the deep signal, using the signal resulting from the inversion for direct modeling the depth configuration to obtain a model signal, and subtracting the model signal from the depth signal to form a look-ahead signal. 7. The method according to any one of paragraphs. 1-6, which includes performing an inversion using the look-ahead signal and the parameters of the layers around the device to obtain resistivities and the positions of the deep layers in front of the drill bit corresponding to the device. 8. The method according to claim 7, which includes analyzing the look-ahead signal during a wellbore drilling operation and deciding on geosteering the wellbore based on the analysis. 9. The method according to claim 7, which includes obtaining resistivities and positions of the deeper layers as the drill bit moves forward and the drilling operation is stopped based on the determination that the changes in resistivity as the drill bit moves forward exceed the threshold for changing the resistivity. 10. A machine-readable storage device having instructions stored therein which, when executed by a machine, cause the machine to perform actions, the actions forming a method according to any one of claims. 1-9. 11. A device for taking measurements in a well, comprising:
many instrument antennas;
a control unit capable of operating when selecting antennas from a plurality of one or more emitter-receiver pairs located to perform one or more in-depth measurements and one or more shallow measurements when the device is operating in a well; and
a data processing unit for processing data of one or more deep measurements and one or more shallow measurements to form a look-ahead signal essentially without contributions from areas adjacent to the sides of the device, while the antennas, the control unit and the data processing unit are capable of performing actions, while the actions contain a method according to any one of paragraphs. 1-9. 12. A device for taking measurements in a well, comprising:
an apparatus having a radiating antenna and a receiving antenna, wherein the radiating antenna and the receiving antenna are arranged to substantially suppress signals from the layers between the radiating antenna and the receiving antenna, or to substantially suppress signals from the layers outside the region between the radiating antenna and the receiving antenna, in response to the operation of the emitter in the well. 13. The device according to p. 12, which includes a control unit and a data processing unit capable of artificially creating an angle of inclination during operation by combining signals from multiple shared antennas of the device, while multiple shared antennas have different angles of inclination. 14. The device according to p. 13, in which the control unit and the data processing unit are adapted to process signals from shared multiple antennas for algorithmic optimization of signal suppression at various dip angles. 15. The device according to claim 13, in which the control unit and the data processing unit are adapted to artificially create an angle of inclination for suppressing signals from layers between multiple shared antennas. 16. The device according to p. 13, in which the control unit and the signal processing unit are adapted to artificially create an angle of inclination for suppressing signals from layers outside the area between multiple shared antennas. 17. The device according to p. 12, in which the radiating antenna and the receiving antenna are located along the longitudinal axis of the device so that at least one of the radiating antenna and the receiving antenna has an angle of inclination relative to the longitudinal axis of the device, the orientation of the radiating antenna and the receiving antenna relative to the longitudinal the axes and relative to each other are selected to substantially suppress signals from the layers between the emitting antenna and the receiving antenna. 18. The device according to p. 12, in which the radiating antenna and the receiving antenna are located along the longitudinal axis of the device so that at least one of the radiating antenna and the receiving antenna has an angle of inclination relative to the longitudinal axis of the device, the orientation of the radiating antenna and the receiving antenna relative to the longitudinal the axes and relative to each other are selected in such a way that signals from layers outside the region between the emitter and the receiver are quickly suppressed. 19. The device according to p. 12, which includes a control unit for performing, when using a radiating antenna and a receiving antenna, absolute depth measurement, relative depth measurement in the presence of an additional receiver or compensated depth measurement in the presence of an additional receiver and additional emitter, so that the signals from layers are substantially suppressed between the antenna pairs from the emitter and receiver with appropriate measurements. 20. The device according to p. 12, in which the device has four antennas located for performing shallow measurements and deep measurements and for essentially suppressing signals from the layers between the four antennas as a result of four antennas. 21. The device according to p. 12, in which the device has fewer than four antennas located for performing shallow measurements and depth measurements and for essentially suppressing signals from the layers between less than four antennas as a result of operation of less than four antennas. 22. The device according to p. 12, in which the device has many antennas arranged in pairs, the first antenna pair of the emitter-receiver has a distance between the emitter and the receiver of the first antenna pair of the emitter-receiver in the range from two feet (0.6 m) to twenty feet (6 m) to perform shallow measurement so that signals from the layers are substantially suppressed between the emitter and the receiver of the first antenna pair of the emitter-receiver, and the second antenna pair of the emitter-receiver has a distance between the emitter and the receiver m second antenna pairs emitter-receiver in the range of twenty feet (6 meters) to a hundred feet (30.48 m) deep to perform measurement such that the signals of the layers substantially suppressed between the transmitter and receiver antenna pair of the second emitter-receiver. 23. The device according to p. 22, in which the emitting antenna of the first antenna pair of the emitter-receiver is located as the emitting antenna of the second antenna pair of the emitter-receiver or the receiving antenna of the first antenna pair of the emitter-receiver is located as the receiving antenna of the second antenna pair of the emitter-receiver. 24. The device according to p. 12, which includes
a plurality of antennas arranged as components of the device, including a radiating antenna and a receiving antenna;
a control unit capable of, during operation, selecting antennas from a plurality of one or more transmitter-receiver pairs located to substantially suppress signals from the layers between the transmitting antenna and the receiving antenna of the corresponding transmitter-receiver pair when the device is operating in a well; and
a data processing unit for processing data from the received signals to form a look-ahead signal substantially without contributions from areas adjacent to the sides of the device. 25. A device for taking measurements in a well, comprising:
many instrument antennas;
a control unit capable of operating when selecting antennas from a plurality of one or more emitter-receiver pairs located to perform one or more in-depth measurements and one or more shallow measurements when the device is operating in a well; and
a data processing unit for processing data from one or more in-depth measurements and one or more shallow-depth measurements to generate a look-ahead signal essentially without contributions from areas adjacent to the sides of the device. 26. The device according to p. 25, in which the data processing unit is able to align the data of one or more shallow measurements, depending on geometric factors, with respect to the data of one or more deep measurements, so that the difference between the data of one or more deep measurements and the aligned data of one or several shallow measurements, a lead-in signal is provided. 27. The device according to p. 25, in which the data processing unit is able to align the data of one or more shallow measurements, depending on the geometric factor, with respect to the data of one or more deep measurements using the inverse filter. 28. The device according to p. 25, in which the data processing unit is capable of performing inversion during operation based on signals from one or more shallow measurements and signals from one or more depth measurements and is capable of subtracting the expected depth signal resulting from the inversion during operation from the measured signal of the deep measurement for the formation of the signal of leading viewing. 29. The device according to p. 25, in which the data processing unit is capable of performing inversion during operation based on signals from one or more shallow measurements without input signals from one or more deep measurements and is capable of subtracting the signal resulting from the inversion used for direct simulation of the deep configuration, for the formation of a signal of leading viewing. 30. The device according to any one of paragraphs. 25-29, in which the source-receiver antenna pairs are selected so that signals from the layers between the radiating antenna and the receiving antenna of the corresponding transmitter-receiver pair are substantially suppressed in response to the operation of the radiating antenna. 31. The method of taking measurements in the well according to any one of paragraphs. 1-9 using the device according to any one of paragraphs. 12-29.

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