CN110764136A - Combined positioning method for time-lapse linear combination and nonlinear combination of anisotropic longitudinal and transverse waves - Google Patents

Combined positioning method for time-lapse linear combination and nonlinear combination of anisotropic longitudinal and transverse waves Download PDF

Info

Publication number
CN110764136A
CN110764136A CN201810839932.3A CN201810839932A CN110764136A CN 110764136 A CN110764136 A CN 110764136A CN 201810839932 A CN201810839932 A CN 201810839932A CN 110764136 A CN110764136 A CN 110764136A
Authority
CN
China
Prior art keywords
event
opj
positioning
equation
shoot
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201810839932.3A
Other languages
Chinese (zh)
Inventor
余波
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China Petroleum and Chemical Corp
Sinopec Geophysical Research Institute
China Petrochemical Corp
Original Assignee
Sinopec Geophysical Research Institute
China Petrochemical Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sinopec Geophysical Research Institute, China Petrochemical Corp filed Critical Sinopec Geophysical Research Institute
Priority to CN201810839932.3A priority Critical patent/CN110764136A/en
Publication of CN110764136A publication Critical patent/CN110764136A/en
Pending legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01VGEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V1/00Seismology; Seismic or acoustic prospecting or detecting
    • G01V1/28Processing seismic data, e.g. analysis, for interpretation, for correction
    • G01V1/288Event detection in seismic signals, e.g. microseismics
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01VGEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V2210/00Details of seismic processing or analysis
    • G01V2210/10Aspects of acoustic signal generation or detection
    • G01V2210/12Signal generation
    • G01V2210/129Source location

Abstract

The invention provides an anisotropic longitudinal and transverse wave travel time linear combination and nonlinear combination combined positioning method. The method utilizes the positioning characteristics of each longitudinal and transverse wave travel time, respectively carries out linear combination and nonlinear combination on a longitudinal wave travel time positioning equation, a transverse wave travel time positioning equation and a longitudinal and transverse wave travel time difference value positioning equation according to the height of positioning contribution, and builds a target equation by summing a linear combination equation and a nonlinear combination equation; then, carrying out perforation positioning analysis by using a target equation to obtain perforation anisotropy parameters; then, carrying out primary positioning analysis on the microseism event by utilizing the perforation anisotropy parameters to obtain a microseism event initial positioning result; and finally, further chromatographic positioning analysis is carried out on the basis of the initial positioning result of the micro-seismic event by using a target equation, and the positioning result of the micro-seismic event with higher positioning precision is inverted by continuously correcting the anisotropic parameters.

Description

Combined positioning method for time-lapse linear combination and nonlinear combination of anisotropic longitudinal and transverse waves
Technical Field
The invention belongs to the technical field of borehole microseism monitoring signal processing, and particularly relates to an anisotropic longitudinal and transverse wave travel time linear combination and nonlinear combination combined positioning method.
Background
The microseism fracturing monitoring technology is one of key technologies in unconventional compact sandstone gas and shale gas reservoir oil and gas field development, and can obtain fracture attributes (main stress trend, fracture width, density and the like) according to inversion-positioned seismic source information for evaluating the fracturing effect, analyzing the fracture induction rule, optimizing well placement and the like. Therefore, in micro-seismic signal processing, the ultimate goal is source localization, also known as the most core technique of micro-seismic signal processing.
The monitoring of the micro earthquake in the well is one of the micro earthquake observation modes, and is characterized in that a three-component detector in the well is used for receiving a micro earthquake full wave field signal. Compared with ground microseism monitoring, the signal-to-noise ratio of data received in a well is high, and the number and types of microseism events are rich. However, unlike the net monitoring of hundreds or thousands of receivers at the surface, because of the limited number of microseismers in a well (typically 12 to 32-stage three-component borehole detectors), it is common for the microseismers in a well to be placed in vertical well sections with typical spacing between receivers of 10 meters. That is to say, the view angle range of the microseism event monitored in the well is very small, and the microseism positioning result which is unstable and has low precision is easy to appear by using the conventional positioning method. In order to solve this problem, a new positioning method with higher positioning accuracy needs to be developed.
At present, the method for positioning the micro earthquake in the well mainly has two ideas: firstly, forward modeling is carried out when events of P waves and S waves travel, a network search method, a simulated annealing method, a geiger method and the like are represented by algorithms, the method has the advantages of easy realization, and the defects that the events of the P waves and the S waves are difficult to accurately pick up when traveling due to weak first arrival phase signals, and positioning results are influenced; and secondly, based on the convolution of the wave equation, the representative algorithm comprises an interference method, a reverse time migration method and a passive source imaging method, the method has the advantages that the first arrival of an event does not need to be picked up, and the defects of high requirements on a data signal-to-noise ratio and a speed model, more detectors and high calculation cost are caused.
In the method, the travel time positioning method is simple and practical and is based on isotropic uniform medium hypothesis, and the method is commonly used for positioning and processing the microseism events in the actual well. However, with the fracturing microseism development of unconventional tight sandstone gas and shale gas reservoir reservoirs, the stratum has anisotropic heterogeneity, the travel time and the propagation path of longitudinal and transverse waves of the microseism are different from the prior isotropy, and the requirement of the positioning precision of the microseism cannot be met by using the existing positioning method.
Disclosure of Invention
In order to solve the technical problems, the invention provides a novel anisotropy longitudinal and transverse wave travel time linear combination and nonlinear combination combined positioning method, and the influence of stratum anisotropy on longitudinal and transverse wave travel time is considered, so that the instability and inaccuracy of positioning of a micro-seismic event are eliminated or reduced, and the requirements of unconventional micro-seismic monitoring of coal bed gas, shale gas and the like are met. The method mainly comprises the following steps:
s1: positioning equation OPJ of time of anisotropy longitudinal wavePAnisotropic transverse wave time-of-flight positioning equation OPJSAnd the anisotropic longitudinal and transverse travel time difference positioning equation OPJPSThe three components are respectively linearly combined OPJ according to the height of the positioning contribution1Non-linear combination OPJ2Establishing target equation OPJ by summing the two;
s2: longitudinal and transverse wave travel time T of pick-up perforationshoot,P、Tshoot,SAs an observed value, combining with a known perforation space position and a known acoustic logging longitudinal and transverse wave velocity, performing positioning analysis on the perforation by using the target equation OPJ, and inverting an exit hole anisotropy parameter delta as { epsilon, delta }, wherein epsilon and delta are two parameters for describing perforation anisotropy;
s3: picking up longitudinal and transverse wave travel time T of microseism eventevent,P、Tevent,SAs an observed value, taking inverted perforation anisotropy parameter delta ═ { epsilon, delta } as a microseism event initial anisotropy parameter, combining known longitudinal and transverse wave velocities of acoustic logging, and carrying out positioning analysis on the microseism event by using the target equation OPJ to obtain a microseism event initial positioning result RTevent={Levent,ZeventIn which L isevent、ZeventRadial coordinates, depth coordinates describing the spatial location of the microseismic event;
s4: and taking the initial positioning result of the micro-seismic event as space constraint, taking the initial anisotropic parameter of the micro-seismic event as parameter constraint, and performing further chromatography positioning processing on the micro-seismic event by using the target equation OPJ in a disturbance range to obtain the final positioning result of the micro-seismic event with higher positioning precision.
According to the embodiment of the invention, the final positioning result of the micro-seismic event obtained in the step S4 needs to satisfy the following conditions: and the error between the longitudinal and transverse wave travel time of the microseism event determined according to the final positioning result of the microseism event obtained in the step S4 and the longitudinal and transverse wave travel time of the microseism event picked up in the step S3 is minimized.
According to an embodiment of the invention, the above target equation OPJ may be:
OPJ=OPJ1+OPJ2
OPJ1=OPJP+OPJS+OPJPS
according to an embodiment of the present invention, the step S2 specifically includes the following steps:
time T of longitudinal and transverse wave of picked perforationshoot,P、Tshoot,SAnd substituting the known perforation space position and the known longitudinal and transverse wave velocities of the acoustic logging into the target equation OPJ to obtain a perforation target equation OPJshoot
OPJshoot=OPJshoot,1+OPJshoot,2
OPJshoot,1=OPJshoot,P+OPJshoot,S+OPJshoot,PS
OPJshoot,P=|Tshoot,P-Tshoot,Pi|
OPJshoot,S=|Tshoot,S-Tshoot,Si|
OPJshoot,PS=|(Tshoot,P-Tshoot,S)-(Tshoot,Pi-Tshoot,Si)|
Wherein, OPJshoot,PFor perforation anisotropy longitudinal wave travel time localization equation, OPJshoot,SFor perforation anisotropy shear wave time-of-flight positioning equation, OPJshoot,PSFor the perforating anisotropy vertical and horizontal wave time difference positioning equation, Tshoot,Pi、Tshoot,SiThe inverted perforation longitudinal and transverse wave travel time is obtained;
and (3) inverting the perforation anisotropy, and solving a perforation anisotropy parameter delta ═ epsilon, delta ] by using the following partial derivative equation:
according to the embodiment of the invention, the solved perforation anisotropy parameter delta ═ { epsilon, delta } needs to satisfy the following condition: the solved perforation anisotropy parameter Δ ═ { ε, δ } enables the perforation target equation OPJshootThe value of (c) is minimized.
According to an embodiment of the present invention, the step S3 specifically includes the following steps:
taking the inverted perforation anisotropy parameter as an initial anisotropy parameter of the microseism event;
time T of longitudinal and transverse waves of picked up microseism eventevent,P、Tevent,SSubstituting the initial anisotropy parameters of the micro-seismic event and the known longitudinal and transverse wave velocities of the acoustic logging into the target equation OPJ to obtain a micro-seismic event target equation OPJevent
OPJevent=OPJevent,1+OPJevent,2
OPJevent,1=OPJevent,P+OPJevent,S+OPJevent,PS
OPJevent,P=|Tevent,P-Tevent,Pi|
OPJevent,S=|Tevent,S-Tevent,Si|
OPJevent,PS=|(Tevent,P-Tevent,S)-(Tevent,Pi-Tevent,Si)|
Wherein, OPJevent,PPositioning equation for microseism anisotropy longitudinal wave travel time, OPJevent,SPositioning equation for microseism anisotropy transverse wave travel time, OPJevent,PSFor microseismic anisotropy longitudinal and transverse wave time difference positioning equation, Tevent,Pi、Tevent,SiThe longitudinal and transverse wave travel time of the inverted microseism event is obtained;
inverting the space position of the microseism event, and solving the initial positioning result RT of the microseism event by using the following partial derivative equationevent={Levent,Zevent}:
According to the embodiment of the invention, the solved initial positioning result RT of the microseism eventevent={Levent,ZeventThe following conditions need to be satisfied: solved micro-seismic event initial positioning result RTevent={Levent,ZeventEnable the microseismic event object equation OPJeventThe value of (c) is minimized.
According to an embodiment of the present invention, each partial derivative equation is preferably solved using a least squares method or a grid search method.
According to an embodiment of the present invention, the step S4 specifically includes the following steps:
taking the initial positioning result of the micro-seismic event as the spatial position center, taking the initial anisotropy parameter of the micro-seismic event as the parameter center, and utilizing the target equation OPJ of the micro-seismic event in the disturbance rangeeventAnd inverting the radial coordinate and the depth coordinate describing the space position of the microseism event and the anisotropy parameter of the microseism event, and solving a final positioning result of the microseism event by using the following partial derivative equation:
according to the embodiment of the present invention, the method for solving the partial derivative equation in step S4 by using the least square method or the grid search method preferably includes the following steps:
within the disturbance range, inverting the corresponding radial coordinate and depth coordinate describing the space position of the microseism event according to the possible value of each microseism event anisotropic parameter, and calculating the error between the estimated microseism event longitudinal and transverse wave travel time and the picked microseism event longitudinal and transverse wave travel time according to the estimated corresponding microseism event longitudinal and transverse wave travel time;
and searching the minimum value of all possible errors, wherein the radial coordinate, the depth coordinate and the anisotropic parameter corresponding to the minimum value are the final positioning result of the micro-seismic event and the corresponding corrected anisotropic parameter of the micro-seismic event.
Compared with the prior art, the invention has the following advantages or beneficial effects:
the invention provides an in-well micro-seismic positioning method based on an anisotropic medium, which is a micro-seismic processing method with higher in-well micro-seismic positioning precision and better effect. Firstly, compared with isotropy, the positioning method provided by the invention considers the formation anisotropy, and the inverted longitudinal and transverse wave travel time is closer to the actual observed value. Secondly, the positioning method provided by the invention utilizes P wave travel time, S wave travel time and PS wave time difference to carry out linear combination and nonlinear combination to establish a target equation for positioning, can fully utilize longitudinal and transverse wave positioning sensitivity compared with the conventional common longitudinal and transverse wave combination, and simultaneously improves the calculation efficiency and the positioning precision by chromatography relocation. The positioning method provided by the invention is simple and feasible, has controllable errors, and can provide reliable technical support for positioning processing of the micro earthquake in the well.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
Drawings
The accompanying drawings are included to provide a further understanding of the technology or prior art of the present application and are incorporated in and constitute a part of this specification. The drawings expressing the embodiments of the present application are used for explaining the technical solutions of the present application, and should not be construed as limiting the technical solutions of the present application.
Fig. 1 is a schematic diagram of a positioning method according to an embodiment of the present invention;
FIG. 2 is a side view of a borehole microseismic observation system according to a second embodiment of the present invention: perforation, geophone, event;
FIG. 3 is a list of borehole microseismic model event space coordinates, anisotropic parameters, according to a second embodiment of the present invention;
FIG. 4 is a table of the true and inverted values of the perforation anisotropy parameters ε, δ, according to a second embodiment of the present invention;
FIG. 5 is a schematic illustration of the results of initial location of a microseismic event obtained based on the inverted perforation anisotropy parameters of FIG. 4;
FIG. 6 is error statistics of the preliminary positioning results of the inverted microseismic event of FIG. 5 and the true spatial location of the microseismic event;
FIG. 7 is a schematic illustration of the final location of the microseismic event obtained by performing further tomographic analysis based on the inverted microseismic event initial location of FIG. 5;
FIG. 8 is a statistical error between the final positioning of the microseismic event inverted from FIG. 7 and the true spatial location of the microseismic event.
Detailed Description
The following detailed description of the embodiments of the present invention will be provided with reference to the accompanying drawings and examples, so that how to apply the technical means to solve the technical problems and achieve the corresponding technical effects can be fully understood and implemented. The embodiments and the features of the embodiments can be combined without conflict, and the technical solutions formed are all within the scope of the present invention.
Example one
The invention provides a longitudinal and transverse wave travel time linear combination and nonlinear combination combined positioning method based on anisotropic media by fully utilizing longitudinal and transverse wave travel time combined positioning. Fig. 1 shows the working principle of the positioning method. The method can be roughly divided into the following four steps:
s1, establishing a longitudinal and transverse wave travel time linear combination and nonlinear combination combined positioning target equation OPJ (hereinafter referred to as target equation OPJ), that is: positioning equation OPJ of time of anisotropy longitudinal wavePAnisotropic transverse wave time-of-flight positioning equation OPJSAnd the anisotropic longitudinal and transverse travel time difference positioning equation OPJPSLinearly combining according to the height of the positioning contribution to establish a linear combination equation OPJ1(ii) a Positioning equation OPJ of time of anisotropy longitudinal wavePAnisotropic transverse wave time-of-flight positioning equation OPJSAnd the anisotropic longitudinal and transverse travel time difference positioning equation OPJPSThe non-linear combination is performed according to the height of the positioning contribution, and a non-linear combination equation OPJ is established2(ii) a And then by combining equations OPJ linearly1And nonlinear combined equation OPJ2Summing to construct target equation OPJ;
s2, obtaining perforating anisotropy parameters epsilon and delta through perforating positioning analysis by using a target equation OPJ;
s3, using the target equation OPJ and the perforation anisotropy parameters epsilon and delta obtained in S2 as the initial anisotropy parameters of the micro seismic event, carrying out preliminary positioning analysis of the micro seismic event, and obtaining the initial positioning result RT of the micro seismic eventevent={Levent,Zevent};
S4, using objective equation OPJ, perform microseismic event tomographic localization analysis, i.e.: setting corresponding disturbance range by taking the initial positioning result of the microseism event as space constraint and the initial anisotropic parameter of the microseism event as parameter constraint, inverting the space position of the microseism event according to a target equation OPJ, continuously correcting the anisotropic parameters epsilon and delta during the inversion, and straighteningThe longitudinal and transverse wave travel time of the inversion is infinitely close to the picked longitudinal and transverse wave travel time (namely infinitely close to the real value of observation), thereby obtaining a microseism event positioning result RT with higher positioning precision* event={L* event,Z* event}。
The following describes the implementation of the above steps.
First, from the target equation OPJ of anisotropic longitudinal travel timePTarget equation OPJ for anisotropic transverse wave travel timeSTarget equation OPJ for anisotropic longitudinal and transverse wave travel timePSThe three components are respectively linearly combined OPJ according to the height of the positioning contribution1Non-linear combination OPJ2The two are summed to establish the target equation OPJ of the present invention:
OPJ=OPJ1+OPJ2(1)
OPJ1=OPJP+OPJS+OPJPS(2)
OPJP=|TP-TPi| (4)
OPJS=|TS-TSi| (5)
OPJPS=|(TP-TS)-(TPi-TSi)| (6)
wherein, TP、TSRespectively, the time of longitudinal and transverse wave travel of the perforation or microseism event picked upPi、TSiRespectively, inverted perforation or micro-seismic event longitudinal and transverse wave travel time. Here, the objective equation OPJ is related to the perforation or microseismic event spatial location (radial coordinate L, depth coordinate Z), anisotropy parameters (. epsilon., Delta), and compressional-compressional velocity (V)P0、VS0) A function of the correlation. In other words, the present invention object equation OPJ has 6 arguments.
Then, the perforation information is input, and the target equation OPJ (equations (1) to (6)) is used to perform the inversion of the perforation anisotropy parameters. In particular, the picked perforation longitudinal and transverse wave travel time Tshoot,P、Tshoot,SAs an actual observed value, the known sonic logging vertical and horizontal velocities and the known perforation spatial positions are substituted into the above-mentioned target equation OPJ (equations (1) to (6)):
OPJshoot=OPJshoot,1+OPJshoot,2(7)
OPJshoot,1=OPJshoot,P+OPJshoot,S+OPJshoot,PS(8)
OPJshoot,P=|Tshoot,P-Tshoot,Pi| (10)
OPJshoot,S=|Tshoot,S-Tshoot,Si| (11)
OPJshoot,PS=|(Tshoot,P-Tshoot,S)-(Tshoot,Pi-Tshoot,Si)| (12)
equation (7) is a function of the anisotropy parameters epsilon and delta only, and the inversion of the perforation anisotropy is realized through the following partial derivative equation:
here, equation (13) may be solved by using a least square method or a grid search method, and a set of anisotropy parameters Δ ═ epsilon, δ is found so that the inverted perforation longitudinal and transverse travel time is infinitely close to the actual observed value, that is, the picked perforation longitudinal and transverse travel time.
Secondly, the target equation OPJ (equations (1) to (6)) is reused, perforation anisotropy parameters are input, micro-seismic event positioning processing is carried out, and accordingly a micro-seismic event initial positioning result RT is obtainedevent. In particular, the longitudinal and transverse wave travel time T of the picked micro-seismic eventevent,P、Tevent,SAs an actual observation value, the perforation anisotropy parameter Δ in the previous inversion is input in combination with the known sonic logging vertical and horizontal velocities, and is substituted into the above-described target equation OPJ (equations (1) to (6)):
OPJevent=OPJevent,1+OPJevent,2(14)
OPJevent,1=OPJevent,P+OPJevent,S+OPJevent,PS(15)
OPJevent,P=|Tevent,P-Tevent,Pi| (17)
OPJevent,S=|Tevent,S-Tevent,Si| (18)
OPJevent,PS=|(Tevent,P-Tevent,S)-(Tevent,Pi-Tevent,Si)| (19)
the time formula (14) is only a function of the radial coordinate L and the depth coordinate Z of the microseismic event, and the inversion of the space position of the microseismic event is realized by the following partial derivative equation:
similarly, equation (20) may be solved by a least squares method or a grid search method, and when the error between the inverted microseismic event longitudinal-transverse travel time and the actual observed value (i.e., the picked microseismic event longitudinal-transverse travel time) is minimized, the corresponding space position RT of the microseismic event is outputevent={Levent,ZeventAnd obtaining the initial positioning result of the microseism event.
Finally, the objective equation OPJ (equations (1) to (6)) is used again to perform further tomographic positioning analysis on the microseismic event, so as to obtain the space position of the microseismic event with higher positioning accuracy and the corresponding corrected anisotropic parameter.
Specifically, due to the small difference between the anisotropic parameter of the location of the micro-seismic event and the location of the perforation, the difference may cause a large error in the positioning result of the micro-seismic event by using the anisotropic parameter of the perforation. To reduce thisThe invention provides a method for further accurately positioning by utilizing a chromatography thought. Solving the microseismic event concrete expression OPJ of the inventionevent
In contrast to the previous step, the microseismic event anisotropy parameters epsilon, delta are simultaneously inverted here in addition to the radial coordinate L, the depth coordinate Z of the microseismic event spatial position. In other words, equation (14) is a function of not only the microseismic event radial coordinate L and the depth coordinate Z, but also the microseismic event anisotropy parameters ∈ and δ. Therefore, the tomographic inversion needs to be implemented by the following four partial derivatives:
likewise, the four partial derivative equations described above can be solved preferably using a least squares method or a grid search method. The specific process is as follows:
initial location of position RT with microseismic eventsevent={Levent,ZeventCentering, and establishing a space grid [ L ] of the microseism event according to the precision requirementevent-ΔL,Levent+ΔL]、[Zevent-ΔZ,Zevent+ΔZ];
Similarly, a microseism event anisotropy parameter grid [ epsilon-delta epsilon, epsilon + delta epsilon ], [ delta-delta, delta + delta ] is established by taking a perforation anisotropy parameter delta as a center;
for the microseism event, all possible values in each anisotropic parameter range are inverted, the radial coordinate and the depth coordinate of the corresponding space position of the microseism event are inverted, however, the ray tracing shows the first arrival travel time of the corresponding longitudinal and transverse waves, the formula (14) is carried, and the error between the travel time of the longitudinal and transverse waves in the process of showing and the travel time of the picked longitudinal and transverse waves is calculated; finding out the minimum value of all possible errors, and the micro-seismic event space position and the anisotropic parameter corresponding to the minimum value, namely the final micro-seismic event chromatographic positioning result RT* event={L* event,Z* eventAnd the corresponding corrected anisotropy parameter Δ*={ε**}。
Example two
In this embodiment, the existing in-well microseismic model data is used to verify the accuracy of the microseismic event location results obtained using the method of the present invention.
The microseism observation example in the well is that a 14-grade downhole detector monitors microseism signals, 1 known perforation signal and 21 microseism event signals, and the radial and depth coordinate geometrical relationship of an observation system is shown in figure 2. The list shown in FIG. 3 is the spatial coordinates of the different source point locations of the microseismic model events in the well and the anisotropy parameters ε and δ corresponding thereto. Before the positioning method is implemented, the existing high-precision ray tracing algorithm is utilized, and according to the observation mode of figure 2 and the anisotropic parameter table of figure 3, the time when each seismic source point reaches the longitudinal and transverse wave travel time of the detector is shown, and the time-travel real value is inverted and input as the known observation value. It should be noted that the effect of the lateral variation velocity, i.e., the VTI medium, is not considered here, and additionally the sonic logging provides the vertical velocity of the shear wave as a known input.
Firstly, according to the expressions (1) to (6) of the invention, the longitudinal and transverse wave nonlinear combination positioning analysis (expressions (7) to (12)) based on the known perforation positions is carried out, and the anisotropy parameters of the exit hole are inverted. In specific operation, the perturbation range of the anisotropy parameter epsilon is selected to be [0, 0.7] and the precision requirement is 0.003, and the perturbation range of the anisotropy parameter delta is selected to be [ -0.1, 0.1] and the precision requirement is 0.001. The solution is obtained by equation (13). The table of figure 4 shows the true and inverted values of the perforation anisotropy parameters epsilon, delta. As can be seen from FIG. 4, the error between the inverted value and the true value is very small, which is very beneficial for the positioning process of the microseismic event in the next step.
Then, the anisotropic parameters obtained by inverting the perforation positioning are input as initial anisotropic parameters of the micro-seismic event, and the real travel time of the longitudinal and transverse waves of the micro-seismic event is taken as an observation object, and the longitudinal and transverse wave travel time nonlinear combined positioning processing (equations (14) to (19)) is directly performed on the micro-seismic event. And (3) searching the spatial position of the micro-seismic event through a solving formula (20), so that the corresponding longitudinal and transverse wave travel time is closest to a real observation value, and taking the spatial position at the moment as an initial positioning result of the micro-seismic event.
It can be seen from fig. 5 that there is some error in the microseismic event location results obtained using the objective equation of the present invention based on the anisotropy analyzed for perforation location (fig. 6 shows the comparison of the inversion value with the true value, where dL _ deta is the radial error and dZ _ deta is the depth error). This means that the difference in anisotropy at different positions causes a certain degree of positioning error, especially in the radial direction.
Finally, in order to further improve the positioning accuracy, further tomographic positioning is performed by using the target equations (14) to (19) of the present invention again on the basis of the initial positioning result of the microseismic event obtained in the previous step, and the equation (21) is solved. Namely, with the initial positioning result of the micro-seismic event as the center, giving a radial +/-25 meter disturbance range and a depth +/-10 meter disturbance range with the precision of 1 meter, giving a disturbance range of an anisotropic parameter epsilon +/-0.3 and a disturbance range of an anisotropic parameter delta +/-0.05 with the precision of 0.001, and inverting the space position and the anisotropic parameter of the micro-seismic event until the travel time error of longitudinal and transverse waves is further reduced and is infinitely close to the true observation value, thereby realizing the final accurate positioning of the micro-seismic event (as shown in fig. 7).
FIG. 8 shows the error statistics of the above-mentioned chromatographic relocation results. As can be seen from fig. 8, the radial, depth positioning error is significantly further reduced. The method fully verifies that the method can realize the positioning processing of the micro-earthquake of the anisotropic medium and obtain the positioning result of the micro-earthquake with higher precision.
It is to be understood herein that while exemplary embodiments of the disclosed systems and methods have been described above, they have been presented for purposes of illustration only and not of limitation. The present disclosure is not intended to be exhaustive or to limit the precise forms disclosed. Thus, modifications and variations are possible in light of the above teachings or may be acquired from practice of the disclosure without departing from the breadth or scope of the disclosure.

Claims (10)

1. An anisotropic longitudinal and transverse wave travel time linear combination and nonlinear combination combined positioning method comprises the following steps:
s1: positioning equation OPJ of time of anisotropy longitudinal wavePAnisotropic transverse wave time-of-flight positioning equation OPJSAnd the anisotropic longitudinal and transverse travel time difference positioning equation OPJPSLinearly combining according to the height of the positioning contribution to establish a linear combination equation OPJ1(ii) a Positioning equation OPJ of time of anisotropy longitudinal wavePAnisotropic transverse wave time-of-flight positioning equation OPJSAnd the anisotropic longitudinal and transverse travel time difference positioning equation OPJPSThe non-linear combination is performed according to the height of the positioning contribution, and a non-linear combination equation OPJ is established2(ii) a By combining equations OPJ linearly1And nonlinear combined equation OPJ2Summing to construct target equation OPJ;
s2: longitudinal and transverse wave travel time T of pick-up perforationshoot,P、Tshoot,SPositioning analysis is carried out on the perforation by utilizing the target equation OPJ in combination with the known perforation space position and the known acoustic logging longitudinal and transverse wave velocity, and anisotropy parameters delta of the perforation are inverted to { epsilon, delta }, wherein epsilon and delta are two parameters for describing the perforation anisotropy;
s3: picking up longitudinal and transverse wave travel time T of microseism eventevent,P、Tevent,STaking inverted perforation anisotropy parameter delta ═ { epsilon, delta } as the initial anisotropy parameter of the microseism event, combining the known longitudinal and transverse wave velocities of the acoustic logging, and carrying out positioning analysis on the microseism event by using the target equation OPJ to obtain the initial positioning result RT of the microseism eventevent={Levent,ZeventIn which L isevent、ZeventRadial coordinates, depth coordinates describing the spatial location of the microseismic event;
s4: and taking the initial positioning result of the micro-seismic event as space constraint, taking the initial anisotropic parameter of the micro-seismic event as parameter constraint, and performing further chromatography positioning processing on the micro-seismic event by using the target equation OPJ in a disturbance range to obtain the final positioning result of the micro-seismic event with higher positioning precision.
2. The positioning method according to claim 1, wherein the final positioning result of the micro-seismic event obtained in the step S4 satisfies the following condition: and (4) according to the final positioning result of the micro-seismic event obtained in the step S4, the error between the longitudinal and transverse wave travel time of the micro-seismic event and the longitudinal and transverse wave travel time of the micro-seismic event picked up in the step S3 is minimized.
3. The method of claim 1, wherein the target equation OPJ is:
OPJ=OPJ1+OPJ2
OPJ1=OPJP+OPJS+OPJPS
4. the positioning method according to claim 3, wherein the step S2 specifically includes the steps of:
time T of longitudinal and transverse wave of picked perforationshoot,P、Tshoot,SAnd substituting the known perforation space position and the known longitudinal and transverse wave velocities of the acoustic logging into the target equation OPJ to obtain a perforation target equation OPJshoot
OPJshoot=OPJshoot,1+OPJshoot,2
OPJshoot,1=OPJshoot,P+OPJshoot,S+OPJshoot,PS
OPJshoot,P=|Tshoot,P-Tshoot,Pi|
OPJshoot,S=|Tshoot,S-Tshoot,Si|
OPJshoot,PS=|(Tshoot,P-Tshoot,S)-(Tshoot,Pi-Tshoot,Si)|
Wherein, OPJshoot,PFor perforation anisotropy longitudinal wave travel time localization equation, OPJshoot,SFor perforation anisotropy shear wave time-of-flight positioning equation, OPJshoot,PSFor the perforating anisotropy vertical and horizontal wave time difference positioning equation, Tshoot,Pi、Tshoot,SiThe inverted perforation longitudinal and transverse wave travel time is obtained;
and (3) inverting the perforation anisotropy, and solving a perforation anisotropy parameter delta ═ epsilon, delta ] by using the following partial derivative equation:
5. the method of claim 4, wherein inverted perforation anisotropy parameter Δ ═ { ε, δ } satisfies the following condition: the perforation anisotropy parameter Δ ═ { ε, δ } enables the perforation target equation OPJshootThe value of (c) is minimized.
6. The positioning method according to claim 3, wherein the step S3 specifically includes the steps of:
taking the inverted perforation anisotropy parameter as an initial anisotropy parameter of the microseism event;
time T of longitudinal and transverse waves of picked up microseism eventevent,P、Tevent,SSubstituting the initial anisotropy parameters of the micro-seismic event and the known longitudinal and transverse wave velocities of the acoustic logging into the target equation OPJ to obtain a micro-seismic event target equation OPJevent
OPJevent=OPJevent,1+OPJevent,2
OPJevent,1=OPJevent,P+OPJevent,S+OPJevent,PS
OPJevent,P=|Tevent,P-Tevent,Pi|
OPJevent,S=|Tevent,S-Tevent,Si|
OPJevent,PS=|(Tevent,P-Tevent,S)-(Tevent,Pi-Tevent,Si)|
Wherein, OPJevent,PPositioning equation for microseism anisotropy longitudinal wave travel time, OPJevent,SPositioning equation for microseism anisotropy transverse wave travel time, OPJevent,PSFor microseismic anisotropy longitudinal and transverse wave time difference positioning equation, Tevent,Pi、Tevent,SiThe longitudinal and transverse wave travel time of the inverted microseism event is obtained;
inverting the space position of the microseism event, and solving the initial positioning result RT of the microseism event by using the following partial derivative equationevent={Levent,Zevent}:
7. The method of claim 6, wherein the obtained initial positioning result RT of the microseismic event is obtainedevent={Levent,ZeventThe following conditions are satisfied: the initial positioning result RT of the microseism eventevent={Levent,ZeventEnable the microseismic event object equation OPJeventThe value of (c) is minimized.
8. The localization method according to claim 4 or 6, wherein each partial derivative equation is solved by using a least squares method or a grid search method.
9. The positioning method according to claim 6, wherein the step S4 specifically includes the steps of:
taking the initial positioning result of the micro-seismic event as the spatial position center, and taking the micro-seismic eventUsing the initial anisotropy parameter as the parameter center, and within the perturbation range, using the microseism event object equation OPJeventAnd inverting the radial coordinate and the depth coordinate describing the space position of the microseism event and the anisotropy parameter of the microseism event, and solving a final positioning result of the microseism event by using the following partial derivative equation:
10. the method according to claim 9, wherein the solving of the partial derivative equation in step S4 by using a least squares method or a grid search method specifically includes the following steps:
within the disturbance range, inverting the corresponding radial coordinate and depth coordinate describing the space position of the microseism event according to the possible value of each microseism event anisotropic parameter, and calculating the error between the estimated microseism event longitudinal and transverse wave travel time and the picked microseism event longitudinal and transverse wave travel time according to the estimated corresponding microseism event longitudinal and transverse wave travel time;
and searching the minimum value of all possible errors, wherein the radial coordinate, the depth coordinate and the anisotropic parameter corresponding to the minimum value are the final positioning result of the micro-seismic event and the corresponding corrected anisotropic parameter of the micro-seismic event.
CN201810839932.3A 2018-07-27 2018-07-27 Combined positioning method for time-lapse linear combination and nonlinear combination of anisotropic longitudinal and transverse waves Pending CN110764136A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810839932.3A CN110764136A (en) 2018-07-27 2018-07-27 Combined positioning method for time-lapse linear combination and nonlinear combination of anisotropic longitudinal and transverse waves

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810839932.3A CN110764136A (en) 2018-07-27 2018-07-27 Combined positioning method for time-lapse linear combination and nonlinear combination of anisotropic longitudinal and transverse waves

Publications (1)

Publication Number Publication Date
CN110764136A true CN110764136A (en) 2020-02-07

Family

ID=69327640

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810839932.3A Pending CN110764136A (en) 2018-07-27 2018-07-27 Combined positioning method for time-lapse linear combination and nonlinear combination of anisotropic longitudinal and transverse waves

Country Status (1)

Country Link
CN (1) CN110764136A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111537345A (en) * 2020-05-12 2020-08-14 西南石油大学 Rapid determination method for transverse isotropic rock sample compression-shear strength parameters

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090259406A1 (en) * 2008-04-09 2009-10-15 Schlumberger Technology Corporation Continuous microseismic mapping for real-time 3d event detection and location
RU2014136780A (en) * 2014-09-11 2016-03-27 Открытое акционерное общество "Акустический институт имени академика Н.Н. Андреева" Method for seismic monitoring of hydrocarbon field development in water areas
CN105549068A (en) * 2015-12-09 2016-05-04 中国科学院地质与地球物理研究所 3D anisotropic micro seismic interference inverse positioning method and 3D anisotropic micro seismic interference inverse positioning system
CN105589100A (en) * 2014-10-21 2016-05-18 中国石油化工股份有限公司 Micro-seismic source location and velocity model simultaneous inversion method
CN106353792A (en) * 2015-07-17 2017-01-25 中国石油化工股份有限公司 Method suitable for positioning hydraulic fracturing micro-seismic source
CN108254780A (en) * 2018-01-22 2018-07-06 河海大学 A kind of microseism positioning and anisotropic velocity structure tomographic imaging method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090259406A1 (en) * 2008-04-09 2009-10-15 Schlumberger Technology Corporation Continuous microseismic mapping for real-time 3d event detection and location
RU2014136780A (en) * 2014-09-11 2016-03-27 Открытое акционерное общество "Акустический институт имени академика Н.Н. Андреева" Method for seismic monitoring of hydrocarbon field development in water areas
CN105589100A (en) * 2014-10-21 2016-05-18 中国石油化工股份有限公司 Micro-seismic source location and velocity model simultaneous inversion method
CN106353792A (en) * 2015-07-17 2017-01-25 中国石油化工股份有限公司 Method suitable for positioning hydraulic fracturing micro-seismic source
CN105549068A (en) * 2015-12-09 2016-05-04 中国科学院地质与地球物理研究所 3D anisotropic micro seismic interference inverse positioning method and 3D anisotropic micro seismic interference inverse positioning system
CN108254780A (en) * 2018-01-22 2018-07-06 河海大学 A kind of microseism positioning and anisotropic velocity structure tomographic imaging method

Non-Patent Citations (8)

* Cited by examiner, † Cited by third party
Title
JUNLUN LI ET AL.: "Joint microseismic location and anisotropic tomography using differential arrival times and differential backazimuths", 《GEOPHYSICAL JOURNAL INTERNATIONAL》 *
JUNLUN LI ET AL.: "Locating Bakken microseismic events with simultaneous anisotropic tomography and extended double-difference method", 《SEG HOUSTON 2013 ANNUAL MEETING》 *
JUNLUN LI ET AL.: "Microseismic joint location and anisotropic velocity inversion for hydraulic fracturing in a tight Bakken reservoir", 《GEOPHYSICS》 *
WEN ZHOU ET AL.: "Microseismic event location using an inverse method of joint P–S phase arrival difference and P-wave arrival difference in a borehole system", 《JOURNAL OF GEOPHYSICS AND ENGINEERING》 *
余波等: "水平旋转与极性判断结合的井中微地震资料震相识别方法", 《石油物探》 *
康玉柱等: "《中国非常规油气地质学》", 28 February 2015, 地质出版社 *
徐奔奔: "地层各向异性对微地震反演定位的影响", 《中国地球科学联合学术年会 2015》 *
黄麟淇等: "各向异性介质中的微震监测和声搜索定位方法", 《东北大学学报(自然科学版)》 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111537345A (en) * 2020-05-12 2020-08-14 西南石油大学 Rapid determination method for transverse isotropic rock sample compression-shear strength parameters

Similar Documents

Publication Publication Date Title
CN104977618B (en) A kind of method evaluated shale gas reservoir and find dessert area
US8666668B2 (en) Multiple anisotropic parameter inversion for a TTI earth model using well data
CN102967882B (en) The modeling method of the interval velocity model on stratum
CN106353792B (en) Method suitable for positioning micro-seismic source of hydraulic fracturing
CN105589100B (en) A kind of microseism hypocentral location and rate pattern Simultaneous Inversion method
US6868037B2 (en) Use of drill bit energy for tomographic modeling of near surface layers
CN101251604B (en) Method for analyzing and NMO correcting two parameters transformation wave speed
Ashida Seismic imaging ahead of a tunnel face with three-component geophones
RU2369884C2 (en) Facility and methods of meausurement of interval time for drilling agent in borehole
US5481501A (en) Method for simulating crosswell seismic data
US7558153B2 (en) Radial profiling of slowness: methods and apparatus for near-wellbore alteration estimation
WO2016041189A1 (en) Method for evaluating shale gas reservoir and seeking desert area
CA2447245C (en) Determination of dipole shear anisotropy of earth formations
CN105652321B (en) A kind of viscous acoustic anisotropy least square reverse-time migration formation method
CN107505654B (en) Full waveform inversion method based on earthquake record integral
CN104200115B (en) Geostatistics simulation based full-formation velocity modeling method
CN105974470B (en) A kind of multi-component seismic data least square reverse-time migration imaging method and system
US7602669B2 (en) Tube-wave seismic imaging
US10768324B2 (en) Method to predict pore pressure and seal integrity using full wavefield inversion
CN102937721B (en) Limited frequency tomography method for utilizing preliminary wave travel time
CN102841376A (en) Retrieval method for chromatography speed based on undulating surface
GB2490278A (en) Multicomponent seismic inversion of VSP data
CN102112894A (en) Estimation of soil properties using waveforms of seismic surface waves
Willis et al. Quantitative quality of distributed acoustic sensing vertical seismic profile data
CN108139499B (en) Q-compensated full wavefield inversion

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination