Method and device for automatically dividing logging target layer
Technical Field
The invention relates to the field of oil and gas exploration and development, in particular to a method and a device for automatically dividing a logging target layer.
Background
With the development of oil and gas exploration technology, logging is widely applied as an important technical means in the oil and gas drilling development process. The accurate division of the logging target layer is the basis for accurately and quickly evaluating the oil-gas layer while drilling in oil-gas drilling.
In the prior art, a logging target layer is divided mainly by adopting the following two modes, wherein one mode is that a field logging technician divides the target layer according to the logging comprehensive information such as drilling time, rock debris lithology, oil gas display and the like, by combining with the comparison and analysis of the conditions of adjacent wells and according to the technical experience and capability of the field logging technician and the knowledge of the geological conditions of the area and the underground; the other mode is that target layer division is carried out by professional software according to corresponding logging information after drilling is completed halfway or after drilling is completed in oil and gas exploration.
However, the first manual partitioning method is easily affected by the technical experience and ability of people, the technical level and the recognition degree of the geological conditions of the region and the underground well. The second method is adopted, the target layer division must be carried out after the drilling is completed halfway or after the drilling is completed, the division cannot be carried out while drilling on a drilling site, and the time lag is large. The method overcomes the defects of influence of human factors and time lag in the logging target layer division in the prior art, and becomes the main research direction of the current logging target layer division.
Disclosure of Invention
In view of the above problems, the present invention provides a method and an apparatus for automatically dividing a logging target layer, so as to overcome the defects of influence of human factors and time lag in the division of the logging target layer in the prior art.
In order to achieve the above object, according to a first aspect of the present invention, there is provided a method for automatically dividing a logging target zone, the method comprising:
analyzing stratum rocks at different depth points in field logging to obtain stratum rock physical index and stratum rock hydrocarbon index corresponding to each depth point;
respectively calculating the base value of the formation rock physical property index and the base value of the formation rock hydrocarbon index corresponding to each depth point according to the formation rock physical property index and the formation rock hydrocarbon index corresponding to each depth point;
respectively calculating and obtaining the amplitude of the stratum rock physical property index and the rate of increase of the stratum rock physical property index corresponding to each depth point according to the stratum rock physical property index corresponding to each depth point and the base value of the stratum rock physical property index;
respectively calculating and obtaining the increase of the hydrocarbon index of the formation rock and the increase rate of the hydrocarbon index of the formation rock corresponding to each depth point according to the hydrocarbon index of the formation rock corresponding to each depth point and the base value of the hydrocarbon index of the formation rock;
comparing the formation rock physical property index, the increase of the formation rock physical property index, the formation rock hydrocarbon index, the increase of the formation rock hydrocarbon index and the increase of the formation rock hydrocarbon index corresponding to each depth point with corresponding preset limit values corresponding to each depth point, screening out the formation rocks corresponding to all the depth points meeting the corresponding preset limit values, and determining the formation rocks as an initial layer;
the corresponding preset limit values comprise preset formation rock physical property index limit values, preset formation rock physical property index amplification limit values, preset formation rock physical property index rate-increasing limit values, preset formation rock hydrocarbon-bearing index amplification limit values and preset formation rock hydrocarbon-bearing index rate-increasing limit values corresponding to the depth points;
and determining the highest value of the hydrocarbon index of the formation rock in the initial layer, and determining the target layer based on the highest value of the hydrocarbon index of the formation rock.
Preferably, the calculating the base value of the formation rock physical property index and the base value of the formation rock hydrocarbon index corresponding to each depth point according to the formation rock physical property index and the formation rock hydrocarbon index corresponding to each depth point includes:
calculating an average value of the stratum rock physical property indexes corresponding to the N depth points, taking the average value as a basic value of the stratum rock physical property index, wherein the value of N is a positive integer greater than 20;
calculating the average value of the hydrocarbon index of the formation rock corresponding to the N depth points, and taking the average value as the base value of the hydrocarbon index of the formation rock, wherein the value of N is a positive integer greater than 20.
Preferably, the obtaining of the increase of the formation rock physical property index and the increase of the formation rock physical property index corresponding to each depth point by calculating according to the formation rock physical property index and the base value of the formation rock physical property index corresponding to each depth point includes:
calculating a difference value between the stratum rock physical property index corresponding to each depth point and a base value of the stratum rock physical property index, and taking the difference value as the amplification of the stratum rock physical property index;
and calculating a ratio between the stratum rock physical property index corresponding to each depth point and a base value of the stratum rock physical property index, and taking the ratio as the increment rate of the stratum rock physical property index.
Preferably, the obtaining of the increase of the hydrocarbon-bearing index of formation rock and the increase of the hydrocarbon-bearing index of formation rock corresponding to each depth point by calculating according to the hydrocarbon-bearing index of formation rock and the base value of the hydrocarbon-bearing index of formation rock corresponding to each depth point includes:
calculating a difference value between the stratum rock hydrocarbon index corresponding to each depth point and a base value of the stratum rock hydrocarbon index, and taking the difference value as an increase of the stratum rock hydrocarbon index;
and calculating a ratio of the formation rock hydrocarbon index corresponding to each depth point to a base value of the formation rock hydrocarbon index, and taking the ratio as the increment rate of the formation rock hydrocarbon index.
Preferably, the determining the highest value of the hydrocarbon index of the formation rock in the initial layer and the determining the target layer based on the highest value of the hydrocarbon index of the formation rock comprise:
comparing the stratum rock hydrocarbon-bearing indexes corresponding to all depth points in the initial layer, and determining the highest value of the stratum rock hydrocarbon-bearing indexes;
searching a depth point which is greater than m% of the highest value of the hydrocarbon-bearing index of the stratum rock in the first corresponding hydrocarbon-bearing index of the stratum rock from bottom to top in a depth interval from the top boundary to the highest value of the hydrocarbon-bearing index of the initial layer as the depth of the top boundary of the target layer;
searching a depth point, which is smaller than n% of the highest value of the hydrocarbon-bearing index of the formation rock, in the first corresponding hydrocarbon-bearing index of the formation rock from bottom to top in the interval from the depth of the highest value of the hydrocarbon-bearing index in the initial layer to the bottom boundary of the initial layer as the bottom boundary depth of the target layer, wherein m and n are positive numbers smaller than 100, and m is smaller than n;
and screening out stratum rocks corresponding to all depth points between the top boundary depth of the target layer and the bottom boundary depth of the target layer from the initial layer, and determining the stratum rocks as the target layer.
According to a second aspect of the present invention, there is provided an apparatus for automatically dividing a logging target zone, the apparatus comprising:
the acquisition module is used for analyzing the stratum rocks at different depth points in the field logging to obtain stratum rock physical index and stratum rock hydrocarbon index corresponding to each depth point;
the first calculation module is used for respectively calculating the base value of the formation rock physical index and the base value of the formation rock hydrocarbon index corresponding to each depth point according to the formation rock physical index and the formation rock hydrocarbon index corresponding to each depth point;
the second calculation module is used for respectively calculating and obtaining the amplitude of the stratum rock physical property index and the increment rate of the stratum rock physical property index corresponding to each depth point according to the stratum rock physical property index and the base value of the stratum rock physical property index corresponding to each depth point;
the third calculation module is used for respectively calculating and obtaining the increase of the hydrocarbon index of the formation rock and the increase rate of the hydrocarbon index of the formation rock corresponding to each depth point according to the hydrocarbon index of the formation rock and the base value of the hydrocarbon index of the formation rock corresponding to each depth point;
the first determining module is used for respectively comparing the formation rock physical property index, the increase of the formation rock physical property index, the increase rate of the formation rock physical property index, the formation rock hydrocarbon index, the increase rate of the formation rock hydrocarbon index and the increase rate of the formation rock hydrocarbon index corresponding to each depth point with corresponding preset limit values, screening out the formation rocks corresponding to all the depth points meeting the corresponding preset limit values, and determining the formation rocks as an initial layer;
the corresponding preset limit values comprise preset formation rock physical property index limit values, preset formation rock physical property index amplification limit values, preset formation rock physical property index rate-increasing limit values, preset formation rock hydrocarbon-bearing index amplification limit values and preset formation rock hydrocarbon-bearing index rate-increasing limit values corresponding to the depth points;
and the second determination module is used for determining the highest value of the hydrocarbon index of the formation rock in the initial layer and determining the target layer based on the highest value of the hydrocarbon index of the formation rock.
Preferably, the first calculation module includes:
the first calculation unit is used for calculating the average value of the stratum rock physical property indexes corresponding to the N depth points, the average value is used as the base value of the stratum rock physical property indexes, and the value of N is a positive integer larger than 20;
and the second calculation unit is used for calculating the average value of the hydrocarbon index of the formation rock corresponding to the N depth points, the average value is used as the base value of the hydrocarbon index of the formation rock, and the value of N is a positive integer greater than 20.
Preferably, the second calculation module includes:
a third calculating unit, configured to calculate a difference between the formation rock property index corresponding to each depth point and a base value of the formation rock property index, and use the difference as an increase of the formation rock property index;
and the fourth calculating unit is used for calculating a ratio between the stratum rock physical property index corresponding to each depth point and a base value of the stratum rock physical property index, and taking the ratio as the increment rate of the stratum rock physical property index.
Preferably, the third computing module comprises:
a fifth calculating unit, configured to calculate a difference between the formation rock hydrocarbon index corresponding to each depth point and a base value of the formation rock hydrocarbon index, and use the difference as an increase of the formation rock hydrocarbon index;
and the sixth calculating unit is used for calculating the ratio of the formation rock hydrocarbon index corresponding to each depth point to the base value of the formation rock hydrocarbon index, and taking the ratio as the increment rate of the formation rock hydrocarbon index.
Preferably, the second determining module includes:
the first determining unit is used for comparing the stratum rock hydrocarbon-bearing indexes corresponding to all depth points in the initial layer and determining the highest value of the stratum rock hydrocarbon-bearing indexes;
a second determining unit, configured to find, from bottom to top, a depth point in the depth interval from the top boundary in the initial layer to the highest value of the hydrocarbon-bearing index, where the depth point is greater than m% of the highest value of the hydrocarbon-bearing index of the formation rock, in the first corresponding formation rock hydrocarbon-bearing index, as the depth of the top boundary of the target layer;
a third determining unit, configured to find, from bottom to top, a depth point in a range from a depth at which a highest value of the hydrocarbon-bearing index in the initial layer is located to a bottom boundary of the initial layer, where m and n are positive numbers smaller than 100 and m is smaller than n, where the depth point is smaller than n% of the highest value of the hydrocarbon-bearing index of the formation rock in the first corresponding formation rock hydrocarbon-bearing index, and the depth point is used as the bottom boundary depth of the target layer;
and the fourth determining unit is used for screening out the stratum rocks corresponding to all depth points between the top boundary depth of the target layer and the bottom boundary depth of the target layer from the initial layer and determining the stratum rocks as the target layer.
Compared with the prior art, the method and the device have the advantages that the formation rocks at different depth points in the field logging are analyzed, the formation rock physical index and the formation rock hydrocarbon index corresponding to each depth point are obtained, and various characteristic values corresponding to the formation rock physical index and the formation rock hydrocarbon index are obtained, so that the initial layer is determined, the target layer is further determined in the initial layer according to the highest value of the formation rock hydrocarbon index, and the defects of influence of human factors and time delay in the logging target layer division in the prior art are overcome.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
Fig. 1 is a schematic flow chart of a method for automatically dividing a logging target layer according to an embodiment of the present invention;
fig. 2 is a flowchart illustrating a detailed process in step S12 of the method for automatically dividing a logging target layer shown in fig. 1 according to an embodiment of the present invention;
fig. 3 is a flowchart illustrating a detailed process in step S13 of the method for automatically dividing a logging target layer shown in fig. 1 according to an embodiment of the present invention;
fig. 4 is a flowchart illustrating a detailed process in step S14 of the method for automatically dividing a logging target layer shown in fig. 1 according to an embodiment of the present invention;
fig. 5 is a flowchart illustrating a detailed process in step S16 of the method for automatically dividing a logging target layer shown in fig. 1 according to an embodiment of the present invention;
fig. 6 is a schematic structural diagram of an apparatus for automatically dividing a logging target layer according to a third embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The terms "first" and "second," and the like in the description and claims of the present invention and the above-described drawings are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "comprising" and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not set forth for a listed step or element but may include steps or elements not listed.
Example one
Referring to fig. 1, a schematic flow chart of a method for automatically dividing a logging target layer according to an embodiment of the present invention is shown, where the method includes the following steps:
s11, analyzing the stratum rocks at different depth points in the field logging, and executing S12 after obtaining stratum rock physical index and stratum rock hydrocarbon index corresponding to each depth point;
the method mainly adopts a comprehensive interpretation technology of oil and gas layers, namely, the stratum rocks are analyzed by applying a mathematical and geological analysis method by utilizing comprehensive data such as real drilling engineering logging while drilling, geological logging, gas logging, materialized logging and the like.
S12, respectively calculating a base value of the formation rock physical property index and a base value of the formation rock hydrocarbon index corresponding to each depth point according to the formation rock physical property index and the formation rock hydrocarbon index corresponding to each depth point, and then executing S13;
s13, respectively calculating and obtaining the amplitude of the stratum rock physical property index and the increment rate of the stratum rock physical property index corresponding to each depth point according to the stratum rock physical property index and the base value of the stratum rock physical property index corresponding to each depth point, and then executing S14;
s14, respectively calculating and obtaining the increase of the hydrocarbon index of the formation rock and the increase rate of the hydrocarbon index of the formation rock corresponding to each depth point according to the hydrocarbon index of the formation rock and the base value of the hydrocarbon index of the formation rock corresponding to each depth point, and then executing S15;
after step S12 is executed, step S13 may be executed first, and then step S14 is executed, or step S14 may be executed first, and then step S13 is executed, that is, step S13 and step S14 do not have a sequential point.
S15, comparing the formation rock physical property index, the increase of the formation rock physical property index, the increase rate of the formation rock physical property index, the formation rock hydrocarbon index, the increase rate of the formation rock hydrocarbon index and the increase rate of the formation rock hydrocarbon index corresponding to each depth point with corresponding preset limit values corresponding to each depth point, screening out the formation rocks corresponding to all the depth points meeting the corresponding preset limit values, and determining the formation rocks as an initial layer;
the corresponding preset limit values comprise preset formation rock physical property index limit values, preset formation rock physical property index amplification limit values, preset formation rock physical property index rate-increasing limit values, preset formation rock hydrocarbon-bearing index amplification limit values and preset formation rock hydrocarbon-bearing index rate-increasing limit values corresponding to the depth points;
specifically, a preset formation rock physical property index threshold value corresponding to each depth point can be preset to be 5, an increase limit value of the preset formation rock physical property index is 3, an increase rate threshold value of the preset formation rock physical property index is 0.35, a preset formation rock hydrocarbon-containing index threshold value is 3, an increase rate threshold value of the preset formation rock hydrocarbon-containing index is 0.2, and an increase rate threshold value of the preset formation rock hydrocarbon-containing index is 0.35; and screening out stratum rocks corresponding to depth points meeting the following requirements: and determining the stratum rock as an initial layer, wherein the corresponding stratum rock physical index value is greater than 5, the increment of the stratum rock physical index is greater than 3, the increment of the stratum rock physical index is greater than 0.35, the stratum rock hydrocarbon index value is greater than 3, the increment of the stratum rock hydrocarbon index is greater than 0.2, and the increment of the stratum rock hydrocarbon index is greater than 0.35.
And S16, determining the highest value of the hydrocarbon index of the formation rock in the initial layer, and determining the target layer based on the highest value of the hydrocarbon index of the formation rock.
According to the method, the stratum rocks at different depth points in field logging are analyzed, the stratum rock physical index and the stratum rock hydrocarbon index corresponding to each depth point are obtained, and various characteristic values corresponding to the stratum rock physical index and the stratum rock hydrocarbon index are obtained, so that an initial layer is determined, a target layer is further determined in the initial layer according to the highest value of the stratum rock hydrocarbon index, and the defects of influence of human factors and time delay in the division of a logging target layer in the prior art are overcome.
Example two
Reference is made to the first embodiment of the present invention and the specific process from S11 to S16 described in fig. 1, which are not described herein again. Specifically, as shown in fig. 2, the step S12 of respectively calculating a base value of the formation rock physical property index and a base value of the formation rock hydrocarbon-bearing index corresponding to each depth point according to the formation rock physical property index and the formation rock hydrocarbon-bearing index corresponding to each depth point specifically includes:
s21, calculating the average value of the stratum rock physical property indexes corresponding to N depth points, taking the average value as the basic value of the stratum rock physical property index, wherein the value of N is a positive integer greater than 20;
s22, calculating the average value of the hydrocarbon index of the formation rock corresponding to the N depth points, and taking the average value as the base value of the hydrocarbon index of the formation rock, wherein the value of N is a positive integer larger than 20.
Preferably, as shown in fig. 3, referring to the first embodiment of the present invention, in step S13 in fig. 1, the respectively calculating and obtaining the increase of the formation rock physical property index and the increase rate of the formation rock physical property index corresponding to each depth point according to the formation rock physical property index and the base value of the formation rock physical property index corresponding to each depth point specifically includes:
s31, calculating a difference value between the stratum rock physical property index corresponding to each depth point and a basic value of the stratum rock physical property index, and taking the difference value as the amplification of the stratum rock physical property index;
s32, calculating a ratio between the stratum rock property index corresponding to each depth point and a base value of the stratum rock property index, and taking the ratio as the increment rate of the stratum rock property index.
Correspondingly, as shown in fig. 4, referring to the first embodiment of the present invention, in step S14 in fig. 1, respectively calculating and obtaining the increase of the hydrocarbon content index of the formation rock and the increase rate of the hydrocarbon content index of the formation rock corresponding to each depth point according to the hydrocarbon content index of the formation rock and the base value of the hydrocarbon content index of the formation rock corresponding to each depth point specifically includes:
s41, calculating a difference value between the formation rock hydrocarbon index corresponding to each depth point and a base value of the formation rock hydrocarbon index, and taking the difference value as the increase of the formation rock hydrocarbon index;
s42, calculating the ratio of the hydrocarbon index of the formation rock corresponding to each depth point to the base value of the hydrocarbon index of the formation rock, and taking the ratio as the increment rate of the hydrocarbon index of the formation rock.
Preferably, as shown in fig. 5, referring to the first embodiment of the present invention, in step S16 in fig. 1, determining the highest value of the hydrocarbon-bearing index of formation rock in the initial layer, and based on the highest value of the hydrocarbon-bearing index of formation rock, determining the target layer specifically includes:
s51, comparing the hydrocarbon index of the formation rock corresponding to each depth point in the initial layer, and determining the highest value of the hydrocarbon index of the formation rock;
s52, searching a depth point which is greater than m% of the highest value of the hydrocarbon-bearing index of the formation rock in the first corresponding hydrocarbon-bearing index of the formation rock from bottom to top in a depth interval from the top boundary in the initial layer to the highest value of the hydrocarbon-bearing index as the depth of the top boundary of the target layer;
s53, searching a depth point, which is smaller than n% of the highest value of the hydrocarbon-bearing index of the formation rock, in the first corresponding hydrocarbon-bearing index of the formation rock from bottom to top in the interval from the depth of the highest value of the hydrocarbon-bearing index in the initial layer to the bottom of the initial layer as the depth of the bottom of the target layer, wherein m and n are positive numbers and m is smaller than n;
s54, screening out stratum rocks corresponding to all depth points between the top boundary depth of the target layer and the bottom boundary depth of the target layer from the initial layer, and determining the stratum rocks as the target layer.
Specifically, for example, taking a real well in the original region as an example, comparing the hydrocarbon content indexes of the formation rocks corresponding to each depth point in the initial layer, determining that the highest value of the hydrocarbon content indexes of the formation rocks is a, and searching a depth point which is greater than 80% of the highest value a of the hydrocarbon content indexes of the formation rocks in the first corresponding hydrocarbon content indexes of the formation rocks from bottom to top in a depth interval from the top boundary in the initial layer to the highest value of the hydrocarbon content indexes as the depth of the top boundary of the target layer; searching a depth point which is smaller than 90% of the highest value a of the hydrocarbon-bearing index of the formation rock in the first corresponding hydrocarbon-bearing index of the formation rock from bottom to top in the interval from the depth of the highest value of the hydrocarbon-bearing index in the initial layer to the bottom boundary of the initial layer as the bottom boundary depth of the target layer; and screening out stratum rocks corresponding to all depth points between the top boundary depth of the target layer and the bottom boundary depth of the target layer from the initial layer, and determining the stratum rocks as the target layer. In the above examples, the values of m% and n% may be set according to the geographical location of the actual well or specific indexes, but the values of m and n are not particularly limited in the present invention to ensure that m and n are positive numbers less than 100 and m is less than n.
According to the technical scheme disclosed by the second embodiment of the invention, the steps of obtaining various characteristic values corresponding to the physical property index of the stratum rock and the hydrocarbon index of the stratum rock corresponding to each depth point and determining the initial layer and the target layer are specifically described, so that the purpose of analyzing and determining the target layer according to the characteristic index of the stratum rock is realized, and the defects of influence of human factors and time lag in the division of the logging target layer in the prior art are overcome.
EXAMPLE III
Corresponding to the method for automatically dividing the logging target layer disclosed in the first embodiment and the second embodiment of the present invention, a third embodiment of the present invention further provides a device for automatically dividing the logging target layer, referring to fig. 6, which is a schematic structural diagram of the device for automatically dividing the logging target layer provided in the third embodiment of the present invention, and the device specifically includes:
the acquisition module 601 is used for analyzing the stratum rocks at different depth points in the field logging to obtain stratum rock physical index and stratum rock hydrocarbon index corresponding to each depth point;
the first calculation module 602 is configured to calculate, according to the formation rock physical property index and the formation rock hydrocarbon index corresponding to each depth point, a base value of the formation rock physical property index and a base value of the formation rock hydrocarbon index corresponding to each depth point respectively;
a second calculating module 603, configured to respectively calculate and obtain an increase rate of the formation rock physical property index and an increase rate of the formation rock physical property index corresponding to each depth point according to the formation rock physical property index and the base value of the formation rock physical property index corresponding to each depth point;
a third calculating module 604, configured to respectively calculate and obtain an increase rate of the hydrocarbon-bearing index of the formation rock and an increase rate of the hydrocarbon-bearing index of the formation rock corresponding to each depth point according to the hydrocarbon-bearing index of the formation rock and the base value of the hydrocarbon-bearing index of the formation rock corresponding to each depth point;
the first determining module 605 is configured to compare the formation rock physical property index, the increase of the formation rock physical property index, the increase rate of the formation rock physical property index, the formation rock hydrocarbon index, the increase rate of the formation rock hydrocarbon index, and the increase rate of the formation rock hydrocarbon index corresponding to each depth point with corresponding preset limit values, screen out formation rocks corresponding to all depth points that satisfy the corresponding preset limit values, and determine the formation rocks as an initial layer;
the corresponding preset limit values comprise preset formation rock physical property index limit values, preset formation rock physical property index amplification limit values, preset formation rock physical property index rate-increasing limit values, preset formation rock hydrocarbon-bearing index amplification limit values and preset formation rock hydrocarbon-bearing index rate-increasing limit values corresponding to the depth points;
a second determining module 606 for determining a highest value of a formation rock hydrocarbon index in the initial layer, and determining the target layer based on the highest value of the formation rock hydrocarbon index.
Specifically, the first calculating module 602 includes:
a first calculating unit 6021, configured to calculate an average value of the formation rock property indexes corresponding to N depth points, where the average value is used as a base value of the formation rock property index, and a value of N is a positive integer greater than 20;
a second calculating unit 6022, configured to calculate an average value of the formation rock hydrocarbon-bearing index corresponding to the N depth points, and use the average value as a base value of the formation rock hydrocarbon-bearing index, where a value of N is a positive integer greater than 20.
The second computing module 603 includes:
a third calculation unit 6031 configured to calculate a difference between the formation rock property index corresponding to each depth point and a base value of the formation rock property index, and use the difference as an increase of the formation rock property index;
a fourth calculating unit 6032, configured to calculate a ratio between the formation rock property index corresponding to each depth point and a base value of the formation rock property index, where the ratio is used as a rate of increase of the formation rock property index.
The third computing module 604, comprising:
a fifth calculation unit 6041 configured to calculate a difference between the formation rock hydrocarbon index corresponding to each depth point and a base value of the formation rock hydrocarbon index, and use the difference as an increase of the formation rock hydrocarbon index;
a sixth calculating unit 6042, configured to calculate a ratio between the formation rock hydrocarbon index corresponding to each depth point and a base value of the formation rock hydrocarbon index, and use the ratio as a rate of increase of the formation rock hydrocarbon index.
The second determining module 606 includes:
a first determining unit 6061, configured to compare the formation rock hydrocarbon-bearing indexes corresponding to the depth points in the initial layer, and determine a highest value of the formation rock hydrocarbon-bearing indexes;
a second determining unit 6062, configured to find, from bottom to top, a depth point in the depth interval from the top boundary in the initial layer to the highest value of the hydrocarbon-bearing index, where the depth point is greater than m% of the highest value of the hydrocarbon-bearing index of the formation rock in the first corresponding formation rock hydrocarbon-bearing index, as the depth of the top boundary of the target layer;
a third determining unit 6063, configured to find, from bottom to top, a depth point in the interval from the depth at which the highest value of the hydrocarbon-bearing index in the initial layer to the initial layer bottom boundary, where m and n are positive numbers smaller than 100 and m is smaller than n, in the first corresponding depth point of the hydrocarbon-bearing index of formation rock, where the depth point is smaller than n% of the highest value of the hydrocarbon-bearing index of formation rock, and the depth point is used as the target layer bottom boundary depth;
a fourth determining unit 6064, configured to screen out, in the initial layer, formation rocks corresponding to all depth points between the target layer top boundary depth and the target layer bottom boundary depth, and determine the formation rocks as the target layer.
In the device for automatically dividing the logging target layer in the third embodiment of the invention, the formation rock physical index and the formation rock hydrocarbon index corresponding to each depth point are obtained through the obtaining module, then the base value of the formation rock physical index and the base value of the formation rock hydrocarbon index corresponding to each depth point are obtained through the first calculating module, then the amplification of the formation rock physical index and the amplification rate of the formation rock physical index corresponding to each depth point, the amplification of the formation rock hydrocarbon index and the amplification rate of the formation rock hydrocarbon index corresponding to each depth point are obtained through the second calculating module and the third calculating module respectively, the initial layer is determined through the first determining module, and finally the target layer is determined through the second determining module, so that the purpose of automatically dividing the target layer according to the characteristics of the formation rock is realized, and the defects of influence of human factors and time delay in the division of the logging target layer in the prior art are overcome.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.