Method and device for determining distribution range of rock stratum

Abstract

The invention discloses a rock stratum distribution range determination method and device, and the method comprises the steps: obtaining a drilled wave impedance curve of a target stratum, a single-frequency amplitude body of the target stratum, and recognizing a wave impedance threshold value of the target stratum; the single-frequency amplitude body is a data body representing the distribution state of the corresponding seismic frequency of the target rock stratum in the target stratum, sparse pulse inversion is performed on the single-frequency amplitude body according to the wave impedance curve, an inversion data body of the target rock stratum can be obtained, and the target rock stratum can be obtained according to the inversion data body and the wave impedance threshold value. According to the method, the rock stratum thickness data of the target rock stratum in the target stratum is obtained, equal-height thickness statistics is conducted on the rock stratum thickness data, the rock stratum distribution range of the target rock stratum in the target stratum is determined, the rock stratum position is calculated and determined from the two dimensions of the stratum section and the plane, and then the accuracy of determination of the rock stratum distribution range is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of determining the distribution range of rock strata, and in particular to a method and device for determining the distribution range of rock strata. Background Art

[0002] The study of fan delta phase is an important part of sedimentary phase research. Fan delta phase is defined as an alluvial fan that advances from adjacent highlands to stable water bodies such as seas and lakes. Fan delta belongs to the steep slope sedimentary environment, with a large terrain slope, close to the source, and a large number of sand and gravel mixed sediments with high mud content, poor sorting and roundness, low maturity of mineral components, coarse sediment grain size, and the main lithology is conglomerate.

[0003] At present, the research on fan delta is limited to the identification of its rock distribution range, and its main technical means is to determine the rock distribution range through the attributes of seismic data. Since seismic data is the superposition of seismic waves in different frequency domains, the attributes of seismic data will be interfered by irrelevant information, resulting in low identification accuracy, especially when fan delta is superimposed and intertwined with other sedimentary environments, it is more difficult to identify and determine the rock distribution range. Moreover, the identification of the rock distribution range cannot determine the depth position of the rock layer, resulting in insufficient accuracy in determining the rock distribution.

[0004] Therefore, how to improve the accuracy of determining the distribution range of rock formations is a technical problem that needs to be solved urgently. Summary of the invention

[0005] The method and device for determining the rock stratum distribution range of the present invention can improve the accuracy of determining the rock stratum distribution range.

[0006] The embodiment of the present invention provides the following solution:

[0007] In a first aspect, an embodiment of the present invention provides a method for determining a rock layer distribution range, the method comprising:

[0008] Obtaining a wave impedance curve of a drilled well of a target formation, a single-frequency amplitude body of the target formation, and a wave impedance threshold for identifying the target formation, wherein the single-frequency amplitude body is a data body characterizing the distribution state of the corresponding seismic frequency of the target formation in the target formation;

[0009] Performing sparse pulse inversion on the single-frequency amplitude volume according to the wave impedance curve to obtain an inversion data volume of the target rock formation;

[0010] Obtaining rock layer thickness data of the target rock layer located in the target stratum according to the inversion data volume and the wave impedance threshold;

[0011] The rock formation thickness data is subjected to iso-thickness statistics to determine the distribution range of the target rock formation in the target stratum.

[0012] In an optional embodiment, obtaining a single-frequency amplitude volume of a target rock formation includes:

[0013] Acquire the target frequency of the target rock formation and the regional seismic data of the target formation, wherein the regional seismic data is the post-stack time domain seismic data of the area where the well has been drilled;

[0014] Data with the same frequency are extracted from the regional seismic data according to the target frequency, and the extracted result is determined as the single-frequency amplitude volume.

[0015] In an optional embodiment, obtaining the target frequency of the target rock formation includes:

[0016] Obtaining the lithology amplitude relationship of the drilled well, wherein the lithology amplitude relationship is the corresponding relationship between different lithologies and seismic amplitudes;

[0017] The frequency of the maximum amplitude corresponding to the target rock layer in the lithology-amplitude relationship is determined as the target frequency.

[0018] In an optional embodiment, after acquiring the regional seismic data of the target formation, the method further includes:

[0019] Acquiring an AC logging curve and a DEN curve of the drilled well;

[0020] A synthetic log calibration is performed based on the AC logging curve and the DEN curve to generate a time-depth scale for quantifying the formation depth corresponding to the regional seismic data.

[0021] In an optional embodiment, obtaining a wave impedance threshold for identifying the target rock formation includes:

[0022] Generating a histogram according to the wave impedance data of the drilled well and the sandstone and mudstone information in the well;

[0023] Determine whether there is a curve intersection in the histogram;

[0024] If so, the wave impedance corresponding to the intersection of the curves is determined as the wave impedance threshold.

[0025] In an optional embodiment, obtaining the rock layer thickness data of the target rock layer located in the target stratum according to the inversion data volume and the wave impedance threshold comprises:

[0026] Traversing the inversion data volume, and determining the inversion data in the inversion data volume that is greater than the wave impedance threshold as target data;

[0027] All the target data are vertically counted, and the statistical results are determined as the rock layer thickness data.

[0028] In an optional embodiment, performing vertical statistics on all the target data and determining the statistical results as the rock layer thickness data includes:

[0029] Accumulating and calculating the target data of each single column in the vertical direction to obtain the vertical data volume of each single column of data;

[0030] According to the formula H=N×T×S, the thickness H of a single rock layer is obtained, wherein N is the amount of vertical data, T is the sampling period of the target data, and S is the seismic wave velocity of the target rock layer;

[0031] The rock layer thickness data is obtained according to the horizontal distribution results of all the single-column rock layer thicknesses.

[0032] In an optional embodiment, performing height-contact thickness statistics on the rock formation thickness data to determine the rock formation distribution range of the target rock formation in the target stratum includes:

[0033] Importing the rock layer thickness data into a contour mapping tool to obtain a rock layer thickness map;

[0034] The areas within different thickness contours in the rock layer thickness map are calculated using an area statistics tool to obtain the distribution range of rock layers at different deposition heights of the target stratum.

[0035] In a second aspect, an embodiment of the present invention further provides a device for determining a rock layer distribution range, the device comprising:

[0036] An acquisition module, used to acquire a wave impedance curve of a drilled well of a target formation, a single-frequency amplitude body of a target formation, and a wave impedance threshold for identifying the target formation, wherein the single-frequency amplitude body is a data body characterizing a distribution state of a corresponding seismic frequency of the target formation in the target formation;

[0037] A first acquisition module is used to perform sparse pulse inversion on the single-frequency amplitude volume according to the wave impedance curve to obtain an inversion data volume of the target rock formation;

[0038] A second acquisition module is used to obtain the rock layer thickness data of the target rock layer located in the target stratum according to the inversion data volume and the wave impedance threshold;

[0039] The determination module is used to perform contour thickness statistics on the rock formation thickness data to determine the distribution range of the target rock formation in the target stratum.

[0040] In a third aspect, an embodiment of the present invention further provides an electronic device, comprising a processor and a memory, wherein the memory is coupled to the processor, and the memory stores instructions, which, when executed by the processor, enable the electronic device to perform the steps of any one of the methods described in the first aspect.

[0041] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any one of the methods described in the first aspect.

[0042] Compared with the prior art, the method and device for determining the distribution range of rock formations of the present invention have the following advantages:

[0043] The present invention obtains the wave impedance curve of the drilled target stratum, the single-frequency amplitude body of the target rock stratum and the wave impedance threshold for identifying the target rock stratum. Since the single-frequency amplitude body is a data body that characterizes the distribution state of the corresponding seismic frequency of the target rock stratum in the target stratum, sparse pulse inversion is performed on the single-frequency amplitude body according to the wave impedance curve to obtain the inversion data body of the target rock stratum. According to the inversion data body and the wave impedance threshold, the rock thickness data of the target rock stratum located in the target stratum is obtained, and the rock distribution range of the target rock stratum in the target stratum is determined by performing contour thickness statistics on the rock thickness data. The method calculates and determines the rock stratum position from two dimensions, namely, the stratum profile and the plane, thereby improving the accuracy of determining the rock stratum distribution range. At the same time, a more accurate understanding of the stratum and lithology can be obtained, which is of great significance for finding lithological oil and gas reservoirs and improving the accuracy of calculating the area and reserves of oil and gas reservoirs. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 A flow chart of a method for determining a rock layer distribution range provided in an embodiment of the present invention;

[0046] Figure 2 A flow chart for determining the deposition range of a fan delta sand body provided for a fan in an embodiment of the present invention;

[0047] Figure 3-1 A schematic diagram of the lithology of Well Y in the time domain seismic section provided by an embodiment of the present invention;

[0048] Figure 3-2 A spectrum amplitude statistical diagram of sandstone-mudstone interlayers and conglomerate provided in an embodiment of the present invention;

[0049] Figure 4 A synthetic record calibration diagram provided by an embodiment of the present invention;

[0050] Figure 5-1 A graph showing the relationship between the frequency spectrum amplitude of the sandstone-mudstone interlayer provided in an embodiment of the present invention;

[0051] Figure 5-2 A graph showing the relationship between the frequency spectrum amplitude of sandstone provided by an embodiment of the present invention;

[0052] Figure 6 A schematic diagram of 15Hz data of the Y well after frequency division provided by an embodiment of the present invention;

[0053] Figure 7 The Y-well wave impedance curve and sandstone and mudstone histograms provided by the embodiment of the present invention;

[0054] Figure 8 An inversion data volume generated by calculation provided by an embodiment of the present invention;

[0055] Fig. 9 A thickness map of the sedimentary range of the gravel body in Well Y provided in an embodiment of the present invention;

[0056] Fig.10 A schematic structural diagram of a device for determining a rock stratum distribution range provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0057] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention belong to the scope of protection of the embodiments of the present invention.

[0058] The rock layer distribution range determination method of the embodiment of the present invention can be applied to the distribution range determination of various rock layers, such as conglomerate or volcanic rock. The embodiment of the present invention will take the identification of the conglomerate deposition range in the northern part of the eastern depression of the Liaohe Depression as an example to specifically explain how to improve the accuracy of its distribution range determination.

[0059] See also Figure 1 , Figure 1 The present invention is a flowchart of a method for determining a rock layer distribution range according to an embodiment of the present invention, the method comprising:

[0060] S11, obtaining the wave impedance curve of the drilled target formation, the single-frequency amplitude body of the target rock formation, and the wave impedance threshold for identifying the target rock formation, wherein the single-frequency amplitude body is a data body that characterizes the distribution state of the corresponding seismic frequency of the target rock formation in the target formation.

[0061] Specifically, the target formation is a formation whose internal rock formation distribution range is to be determined. It can be a formation for oil and gas exploration or development, or a formation with similar sedimentary phases of sandstone and conglomerate that needs to be studied. It is sufficient that there is a drilled well on the target formation. The wave impedance curve can be obtained by fitting the wave impedance data. The wave impedance data is obtained based on the logging data of the drilled well. For example, the wave impedance curve (or IMP curve) of the drilled well is calculated based on the AC curve (or acoustic wave time difference curve) and DEN curve (or density curve) of the drilled well. The wave impedance curve represents the calculation results of the AC curve and DEN curve of the drilled well. The single-frequency amplitude body and wave impedance threshold can be obtained through the database, or can be calculated based on the information data of the drilled well and the logging data.

[0062] In practical applications, since logging data is expressed in time as logging depth, if there is a deviation in the correspondence between seismic wave time and logging depth, the accuracy of single-frequency amplitude volume calculation will be insufficient. Figure 2 , Figure 2 This is a flow chart for determining the range of fan delta sand body deposition. Taking the study area in the northern part of the eastern sag of Liaohe Depression as the target stratum, the upper layer of the sandstone in the stratum in this area is sandstone and mudstone interbedded. According to regional geological knowledge, the sandstone and conglomerate in the drilled well (Y well) are fan delta facies deposits. Please refer to Figure 3-1 , Figure 3-1 This is a time domain seismic profile of the region. In the upper sub-section of Sha San that has been drilled in the region, 276 meters of sandstone and conglomerate were encountered from 3309 meters to 3585 meters (well depth 3585 meters). The lithology profiles at depths of 3350-3450 meters and 3500-3600 meters in the figure are all sandstone and conglomerate, and the corresponding logging curve amplitude is small. In order to ensure the accuracy of the calculation of the single-frequency amplitude body, the synthetic records of the drilled wells are first calibrated to establish an accurate time-depth relationship, and then the spectral amplitude statistics of the seismic data of the sandstone-mudstone interlayer and the sandstone and conglomerate are performed. Therefore, the calculation and acquisition of the single-frequency amplitude body can be implemented in the following ways, including:

[0063] The first step is to obtain the target frequency of the target rock formation and the regional seismic data of the target formation, where the regional seismic data is the post-stack time domain seismic data of the area where the well is located, such as the seismic data of the target formation. Regional seismic data is the corresponding data of seismic acquisition data. By releasing seismic waves (such as blasting) at a preset position in the area and receiving the reflected signal at another position, multiple blasting points and receiving points are set, and after processing, it can become seismic data. For example: the seismic team collects 300m 2 Seismic data, this 300m 2 As long as there are AC curves for all wells within the range, the time-depth relationship can be calculated by synthetic record calibration and displayed on the time domain seismic data. This is not the seismic data of a certain well, but the post-stack time domain seismic data within the range of the drilled wells.

[0064] In order to quantify the corresponding stratum depth of the regional seismic data, in a specific embodiment, after obtaining the regional seismic data of the target stratum, the method further includes:

[0065] Get the AC logging curve and DEN curve of the drilled well; perform synthetic record calibration based on the AC logging curve and DEN curve to generate a time-depth scale corresponding to the formation depth of the quantitative regional seismic data. Figure 3-2 In the figure, the vertical axis 1500-2500 is time, in ms. The AC logging curve and the initial seismic data can be calibrated by synthetic recording to establish an accurate time-depth relationship. The Y well lithology data, logging data and post-stack time domain seismic data can be accurately matched to obtain regional seismic data with accurate time-depth relationship. Figure 3-2 That is, it represents the shape of regional seismic data. It can be understood that when implementing calibration, since the lithology at different depths in Well Y is determined, different lithologies correspond to different curve amplitudes; the amplitude shape represented by the logging curve is also determined, and calibration can be implemented based on the lithology of Well Y and the curve amplitude of the logging curve. It should be noted that Figure 3-2 The bottom area of ​​Well Y is Figure 3-1 There is a corresponding relationship between the lithological profiles of the wells, and the lithology they illustrate is the same.

[0066] See also Figure 4 , Figure 4 For synthetic record calibration diagram, the unit of depth data of the drilled well is m (meter), and the unit of time domain data of seismic data is ms (milliseconds). It is impossible to characterize the formation depth corresponding to the seismic data. Synthetic record calibration can be performed based on AC logging curve and DEN curve to establish the corresponding relationship between formation depth and seismic wave transmission time. After characterization through time-depth scale, synthetic record calibration can obtain a certain time on the seismic data corresponding to a certain depth of the drilled well. Synthetic record calibration uses AC curve and DEN curve to calculate wave impedance curve, wave impedance curve, sub-wave and reflection coefficient to calculate seismic waves, and compares the calculated seismic waves with the collected wellside seismic data to determine the time-depth scale, that is, to correspond the formation depth and seismic wave transmission time, so that the depth data of the drilled well can be displayed on the time-domain seismic data.

[0067] The target frequency is the frequency corresponding to the target rock formation, and the lithology amplitude relationship of the drilled well is obtained. The lithology amplitude relationship is the corresponding relationship between different lithologies and seismic amplitudes. The spectrum amplitude analysis tool can be used to perform spectrum amplitude analysis on different depth ranges of Well Y, and the frequency corresponding to the maximum amplitude of the target rock formation in the lithology amplitude relationship is determined as the target frequency. Figure 5-1 From the frequency spectrum amplitude relationship of the sand-mud interlayer in Well Y, it can be concluded that the frequency corresponding to the maximum amplitude is 20 Hz. Figure 5-2It can be concluded that the frequency corresponding to the maximum amplitude of conglomerate is 15 Hz, and the amplitude of conglomerate reaches its maximum at 15 Hz. Therefore, it can be concluded that the amplitude of 15 Hz frequency seismic data has a good correlation with conglomerate, and 15 Hz can be determined as the target frequency of conglomerate.

[0068] The second step is to extract data with the same frequency from the regional seismic data according to the target frequency, and determine the extracted results as single-frequency amplitude volumes. Extracting data with the same frequency can be implemented based on software tools. Taking the distribution range of conglomerate as an example, the Single Frequency function in the Geoeast software attribute module can be used to extract a 15Hz single-frequency amplitude volume. The extraction results can be found in Figure 6 , Figure 6 Characterizes the Figure 3-2 The result of extracting data at the target frequency of 15 Hz shows that the red part (type a area) has a high amplitude value, indicating that the area is sandstone, and the blue part (type b area) has a low amplitude value, indicating that the area is mudstone.

[0069] Similarly, the wave impedance threshold can also be calculated, including generating a histogram based on the wave impedance data of the drilled well and the sandstone and mudstone information in the well. The sandstone and mudstone information in the well characterizes the distribution information of sandstone and mudstone in the drilled well. The wave impedance curve generated when the synthetic record of Well Y is calibrated and the lithology distribution in Well Y can be used to generate a histogram. Please refer to Figure 7 , the solid line in the figure is the wave impedance curve of mudstone (or mudstone), and the dotted line in the figure is the wave impedance curve of sandstone (or sandstone); determine whether there is a curve intersection in the histogram; in the histogram, the value greater than the curve intersection is identified as sandstone, and the value less than the curve intersection is identified as mudstone, so the wave impedance value corresponding to the curve intersection is determined as the wave impedance threshold. After obtaining the wave impedance curve, the single-frequency amplitude body and the wave impedance threshold, enter step S12.

[0070] S12. Perform sparse pulse inversion on the single-frequency amplitude volume according to the wave impedance curve to obtain an inversion data volume of the target rock formation.

[0071] Specifically, sparse pulse inversion is to use the advantages of sparsely generated signals and the gain reverse integration method to calculate the reflection, attenuation, scattering and other characteristics of the signal in space. Sparse pulse inversion can be performed on the single-frequency amplitude volume based on the wave impedance curve through software tools to obtain the inversion data volume. Sparse pulse inversion can also be performed based on the wave impedance curve, seismic data generated by frequency division data, and seismic wavelets extracted from the seismic traces near the Y well. Please refer to Figure 8 , Figure 8 In order to implement the characterization result of the inversion data volume after the sparse pulse inversion, step S13 is entered after the inversion data volume is obtained.

[0072] S13. Obtaining rock thickness data of the target rock layer located in the target stratum according to the inversion data volume and the wave impedance threshold.

[0073] Specifically, the wave impedance threshold represents the minimum wave impedance for identifying the target rock formation. The data in the inversion data body can be binarized based on the wave impedance threshold, and the rock formation thickness data can be determined based on the data in the inversion data body that is greater than the wave impedance threshold. The rock formation thickness data represents the thickness distribution state of the target rock formation in the target stratum.

[0074] In a specific implementation, obtaining the rock thickness data of the target rock layer located in the target stratum according to the inversion data volume and the wave impedance threshold includes:

[0075] The first step is to traverse the inversion data body and determine the inversion data in the inversion data body that is greater than the wave impedance threshold as the target data; this can be processed based on the calculator of the geoeast software, the wave impedance threshold is set to 11000, variable A is set, and the current data of the inversion data body is assigned to variable A, and the judgment statement if A>11000, y=1, else A=0 is used. After calculation, the values ​​in the inversion data body that are greater than 11000 are assigned a value of 1, and those that are less than 11000 are assigned a value of 0. In this way, the data that the inversion data body considers to be sandstone is 1, that is, the target data, and the other data that is not sandstone is 0.

[0076] In the second step, all target data are vertically counted and the statistical results are determined as rock thickness data. The inversion data body is a three-dimensional structure, and the target data after wave impedance threshold comparison and screening is also a three-dimensional structure, which is used to characterize the distribution of the target rock layer in the target stratum. Vertical statistics are used to determine the number of each single column of data, and then determine the rock layer thickness represented by the single column position based on the number of data. Specifically, it includes accumulating the target data of each single column in the vertical direction to obtain the vertical data volume of each single column data; obtaining the single column rock layer thickness H according to the formula H=N×T×S, wherein N is the vertical data volume, T is the sampling period of the target data, S is the seismic wave velocity of the target rock layer, the sampling period represents the interval time between two adjacent target data in the single column data, the product of the vertical data volume and the sampling period represents the total time of the column target data, and the single column rock layer thickness can be obtained by multiplying it with the seismic wave velocity; according to the horizontal distribution results of all the single column rock layer thicknesses, the rock layer thickness data is obtained, and in this way, the rock layer thickness represented by each single column data can be accurately calculated, and the rock layer thickness data of the target rock layer can be obtained based on the rock layer thickness of all columns, and after obtaining the rock layer thickness data, step S14 is entered.

[0077] S14, performing height-contact thickness statistics on the rock formation thickness data to determine the distribution range of the target rock formation in the target stratum.

[0078] Specifically, the contour thickness statistics can be calculated based on the contour mapping tool or the sequence stratigraphic statistics tool. The contour thickness statistics is to determine the distribution range of the target rock layer with the same thickness. The data with the same thickness in the rock layer thickness data can be selected to fit the curve of the rock layer distribution range, and the rock layer distribution range can be determined based on the range curve. For example, the rock layer thickness data with a contour line of 0 is counted, and the fitted curve is the rock layer distribution range of the target rock layer in the target stratum.

[0079] In one possible implementation, the formation thickness data can be imported into a contour mapping tool to obtain a formation thickness map; see Fig. 9 The 0-line range in the figure is the distribution of the target stratum. The thickness of the rock strata can also be calculated at 150m, 200m and 300m to accurately obtain the depositional range of gravel bodies at different heights. The area statistics tool can then be used to calculate the areas within different thicknesses in the rock stratum thickness map to obtain the distribution range of rock strata at different depositional heights of the target stratum.

[0080] Based on the same inventive concept as the determination method, the embodiment of the present invention also provides a device for determining the distribution range of rock formations, see Fig.10 , the device comprises:

[0081] An acquisition module 101 is used to acquire a wave impedance curve of a target formation that has been drilled, a single-frequency amplitude body of the target formation, and a wave impedance threshold for identifying the target formation, wherein the single-frequency amplitude body is a data body that characterizes the distribution state of the corresponding seismic frequency of the target formation in the target formation;

[0082] A first acquisition module 102 is used to perform sparse pulse inversion on the single-frequency amplitude volume according to the wave impedance curve to obtain an inversion data volume of the target rock formation;

[0083] A second obtaining module 103 is used to obtain the rock thickness data of the target rock layer located in the target stratum according to the inversion data volume and the wave impedance threshold;

[0084] The determination module 104 is used to perform contour thickness statistics on the rock formation thickness data to determine the distribution range of the target rock formation in the target stratum.

[0085] In an optional embodiment, the acquisition module includes:

[0086] An acquisition submodule, used for acquiring a target frequency of the target rock formation and regional seismic data of the target formation, wherein the regional seismic data is post-stack time domain seismic data of the area where the well has been drilled;

[0087] The first determination submodule is used to extract data with the same frequency from the regional seismic data according to the target frequency, and determine the extraction result as the single-frequency amplitude volume.

[0088] In an optional embodiment, the acquisition submodule includes:

[0089] A first acquisition unit is used to acquire the lithology amplitude relationship of the drilled well, wherein the lithology amplitude relationship is a correspondence relationship between different lithologies and seismic amplitudes;

[0090] A determination unit is used to determine the frequency of the maximum amplitude corresponding to the target rock layer in the lithology amplitude relationship as the target frequency.

[0091] In an optional embodiment, the acquisition module further includes:

[0092] A second acquisition unit is used to acquire the AC logging curve and the DEN curve of the drilled well;

[0093] The first acquisition unit is used to perform synthetic record calibration according to the AC logging curve and the DEN curve to generate a time-depth scale for quantifying the formation depth corresponding to the regional seismic data.

[0094] In an optional embodiment, the acquisition module further includes:

[0095] A generating submodule, used for generating a histogram according to the wave impedance data of the drilled well and the sandstone and mudstone information in the well;

[0096] A judgment submodule, used to judge whether there is a curve intersection in the histogram;

[0097] The second determining submodule is used to determine the wave impedance corresponding to the curve intersection as the wave impedance threshold when there is a curve intersection in the histogram.

[0098] In an optional embodiment, the second obtaining module includes:

[0099] A third determination submodule, configured to traverse the inversion data volume, and determine inversion data in the inversion data volume that is greater than the wave impedance threshold as target data;

[0100] The fourth determination submodule is used to perform vertical statistics on all the target data and determine the statistical results as the rock layer thickness data.

[0101] In an optional embodiment, the fourth determining submodule includes:

[0102] A second obtaining unit is used to perform cumulative calculation on the target data of each single column in the vertical direction to obtain the vertical data volume of each single column of data;

[0103] A third obtaining unit is used to obtain a single-column rock layer thickness H according to a formula H=N×T×S, wherein N is the vertical data volume, T is the sampling period of the target data, and S is the seismic wave velocity of the target rock layer;

[0104] The fourth obtaining unit is used to obtain the rock layer thickness data according to the horizontal distribution results of all the single-column rock layer thicknesses.

[0105] In an optional embodiment, the determining module includes:

[0106] A fifth obtaining unit, used for importing the rock layer thickness data into a contour mapping tool to obtain a rock layer thickness map;

[0107] The sixth obtaining unit is used to calculate the areas within different thickness contours in the rock layer thickness map according to an area statistics tool to obtain the distribution range of rock layers at different deposition heights of the target stratum.

[0108] Based on the same inventive concept as the determination method, an embodiment of the present invention also provides an electronic device, including a processor and a memory, wherein the memory is coupled to the processor, and the memory stores instructions, which, when executed by the processor, enable the electronic device to perform the steps of any one of the methods described in the determination method.

[0109] An embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the steps of any one of the methods described in the determination method are implemented.

[0110] The technical solution provided in the embodiments of the present invention has at least the following technical effects or advantages:

[0111] By obtaining the wave impedance curve of the drilled well of the target formation, the single-frequency amplitude body of the target rock formation and the wave impedance threshold for identifying the target rock formation, since the single-frequency amplitude body is a data body that characterizes the distribution state of the corresponding seismic frequency of the target rock formation in the target formation, sparse pulse inversion is performed on the single-frequency amplitude body according to the wave impedance curve, and the inversion data body of the target rock formation can be obtained. According to the inversion data body and the wave impedance threshold, the rock thickness data of the target rock formation located in the target formation is obtained, and the rock distribution range of the target rock formation in the target formation is determined by performing contour thickness statistics on the rock thickness data. This method calculates and determines the rock position from two dimensions, namely, the stratigraphic profile and the plane, thereby improving the accuracy of determining the rock distribution range. At the same time, a more accurate understanding of the stratigraphy and lithology can be obtained, which is of great significance for finding lithologic oil and gas reservoirs and improving the accuracy of calculating the area and reserves of oil and gas reservoirs.

[0112] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0113] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (modules, systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0114] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0115] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0116] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0117] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for determining the distribution range of rock formations, characterized in that: The method comprises: Obtaining a wave impedance curve of a drilled well of a target formation, a single-frequency amplitude body of the target formation, and a wave impedance threshold for identifying the target formation, wherein the single-frequency amplitude body is a data body characterizing the distribution state of the corresponding seismic frequency of the target formation in the target formation; Performing sparse pulse inversion on the single-frequency amplitude volume according to the wave impedance curve to obtain an inversion data volume of the target rock formation; Obtaining rock layer thickness data of the target rock layer located in the target stratum according to the inversion data volume and the wave impedance threshold; The rock formation thickness data is subjected to iso-thickness statistics to determine the distribution range of the target rock formation in the target stratum.

2. The method for determining the rock layer distribution range according to claim 1, characterized in that: Obtain the single-frequency amplitude volume of the target rock formation, including: Acquire the target frequency of the target rock formation and the regional seismic data of the target formation, wherein the regional seismic data is the post-stack time domain seismic data of the area where the well has been drilled; Data with the same frequency are extracted from the regional seismic data according to the target frequency, and the extracted result is determined as the single-frequency amplitude volume.

3. The method for determining the rock layer distribution range according to claim 2, characterized in that: Acquiring a target frequency of the target rock formation includes: Obtaining the lithology amplitude relationship of the drilled well, wherein the lithology amplitude relationship is the corresponding relationship between different lithologies and seismic amplitudes; The frequency of the maximum amplitude corresponding to the target rock layer in the lithology-amplitude relationship is determined as the target frequency.

4. The method for determining the distribution range of rock formations according to claim 2, characterized in that: After acquiring the regional seismic data of the target stratum, the method further comprises: Acquiring an AC logging curve and a DEN curve of the drilled well; A synthetic log calibration is performed based on the AC logging curve and the DEN curve to generate a time-depth scale for quantifying the formation depth corresponding to the regional seismic data.

5. The method for determining the distribution range of rock formations according to claim 1, characterized in that: Obtaining a wave impedance threshold for identifying the target rock formation includes: Generating a histogram according to the wave impedance data of the drilled well and the sandstone and mudstone information in the well; Determine whether there is a curve intersection in the histogram; If so, the wave impedance corresponding to the intersection of the curves is determined as the wave impedance threshold.

6. The method for determining the distribution range of rock formations according to claim 1, characterized in that: The step of obtaining the rock layer thickness data of the target rock layer located in the target stratum according to the inversion data volume and the wave impedance threshold comprises: Traversing the inversion data volume, and determining the inversion data in the inversion data volume that is greater than the wave impedance threshold as target data; All the target data are vertically counted, and the statistical results are determined as the rock layer thickness data.

7. The method for determining the distribution range of rock formations according to claim 6, characterized in that: The vertical statistics of all the target data are performed, and the statistical results are determined as the rock layer thickness data, including: Accumulating and calculating the target data of each single column in the vertical direction to obtain the vertical data volume of each single column of data; According to the formula H=N×T×S, the thickness H of a single rock layer is obtained, wherein N is the amount of vertical data, T is the sampling period of the target data, and S is the seismic wave velocity of the target rock layer; The rock layer thickness data is obtained according to the horizontal distribution results of all the single-column rock layer thicknesses.

8. The method for determining the distribution range of rock formations according to claim 1, characterized in that: Performing height-contact thickness statistics on the rock formation thickness data to determine the distribution range of the target rock formation in the target stratum includes: Importing the rock layer thickness data into a contour mapping tool to obtain a rock layer thickness map; The areas within different thickness contours in the rock layer thickness map are calculated using an area statistics tool to obtain the distribution range of rock layers at different deposition heights of the target stratum.

9. A device for determining the distribution range of rock formations, characterized in that: The device comprises: An acquisition module, used to acquire a wave impedance curve of a drilled well of a target formation, a single-frequency amplitude body of a target formation, and a wave impedance threshold for identifying the target formation, wherein the single-frequency amplitude body is a data body characterizing a distribution state of a corresponding seismic frequency of the target formation in the target formation; A first acquisition module is used to perform sparse pulse inversion on the single-frequency amplitude volume according to the wave impedance curve to obtain an inversion data volume of the target rock formation; A second acquisition module is used to obtain the rock layer thickness data of the target rock layer located in the target stratum according to the inversion data volume and the wave impedance threshold; The determination module is used to perform contour thickness statistics on the rock formation thickness data to determine the distribution range of the target rock formation in the target stratum.

10. An electronic device, characterized in that: The electronic device comprises a processor and a memory, wherein the memory is coupled to the processor and stores instructions, and when the instructions are executed by the processor, the electronic device executes the steps of the method according to any one of claims 1 to 8.

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