Method and device for identifying types of hydrocarbon source rocks in offshore sea-land transition phase less well area

Abstract

The invention relates to a method and a device for identifying hydrocarbon source rock types in a well area with less offshore sea-land transition facies. The identification method comprises the following steps: S1, acquiring required data; s2, according to the sporopollen phase analysis data, determining a hydrocarbon source rock division threshold value based on the sporopollen phase component content; s3, according to the hydrocarbon source rock division threshold value based on the sporopollen phase component content, determining the threshold value of the biogenic indication parameter of the biomarker compound corresponding to the hydrocarbon source rock and the condensate oil; s4, according to the threshold value of the biogenic indication parameter of the biomarker compound corresponding to the condensate oil, determining the threshold value of the natural gas light hydrocarbon parameter; and S5, drawing a cross plot according to the natural gas light hydrocarbon parameters, and dividing ranges corresponding to different types of hydrocarbon source rocks according to the threshold values of the natural gas light hydrocarbon parameters. According to the identification method and device provided by the invention, the identification accuracy of the hydrocarbon source rock type of the offshore sea-land transition facies sedimentary environment less-well area is remarkably improved, and the problem of limited samples in the less-well area is solved.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas exploration, and in particular to a method and a device for identifying the type of source rock in an offshore marine-continental transitional phase well-pollinated area. Background Art

[0002] The marine-continental transitional sedimentary environment is widely developed in China's offshore areas, and the oil and gas resources are rich. Under the marine-continental transitional background, various types of sedimentary facies are developed, including delta, tidal flat, lagoon, coastal shallow sea and other sedimentary environments. The understanding of the types of marine-continental transitional source rocks and the distribution range of source rocks are of decisive significance to the exploration deployment strategy.

[0003] At present, the identification of source rock types mainly adopts the methods of rock pyrolysis and molecular geochemical indicators. A series of parameters have been applied relatively maturely in terrestrial delta phase, lacustrine phase and marine source rocks. Different types of source rocks can be identified based on the characteristic geochemical parameter values ​​and the corresponding intersection plates. However, the sedimentary environment of marine-continental transitional source rocks is different from both the terrestrial and marine phases, and it is difficult to distinguish them with commonly used indicators. In addition, the number of offshore drilling is small, and oil and gas discoveries are the main ones. The revelation of source rocks is limited, and it is impossible to collect enough source rock samples for testing and analysis.

[0004] Therefore, providing a method for identifying source rock types in offshore marine-continental transitional phase areas with few wells is a technical problem that needs to be solved in the current field. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method and device for identifying the type of source rock in offshore marine-continental transitional phase areas with few wells. Compared with the prior art, the identification method provided by the present invention comprehensively utilizes sporophase analysis data, biomarker compound parameters and natural gas light hydrocarbon parameters, which significantly improves the accuracy of identifying the type of source rock in offshore marine-continental transitional phase sedimentary environments with few wells, and solves the problem of limited samples in areas with few wells.

[0006] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a method for identifying source rock types in offshore marine-continental transitional phase areas with few wells, the identification method comprising the following steps:

[0008] S1, obtain the palynological data of source rocks, saturated hydrocarbon chromatography-mass spectrometry data of source rocks, saturated hydrocarbon chromatography-mass spectrometry data of condensate oil and chromatographic data of light hydrocarbons of natural gas in the study area;

[0009] S2, according to the palynological phase analysis data described in step S1, determining the boundary value of source rock division based on the content of palynological phase components;

[0010] S3, determining the boundary value of the source rock and the source rock corresponding to the condensate oil according to the source rock classification boundary value based on the content of the sporofacies component in step S2;

[0011] S4, determining the limit value of the natural gas light hydrocarbon parameter according to the limit value of the source indicator parameter of the biomarker compound corresponding to the condensate oil in step S3;

[0012] S5, drawing an intersection diagram according to the natural gas light hydrocarbon parameters, and dividing the ranges corresponding to different types of source rocks according to the limit values ​​of the natural gas light hydrocarbon parameters in step S4.

[0013] In the identification method provided by the present invention, the source rocks in the drilled area are divided into delta-swamp and tidal flat-lagoon types according to the palynological phase analysis data of the source rocks. On this basis, the limit values ​​of the biomarker compound source indicator parameters of the two types of source rocks are established, and then the limit values ​​of the natural gas light hydrocarbon parameters are determined by the condensate oil biomarker compound source indicator parameters. Finally, the division area of ​​the source rock type is obtained through the intersection plate of the drilled natural gas light hydrocarbons.

[0014] In the present invention, the biogenic indicator parameters of the biomarker compounds are mainly used to indicate the source and environment of organic matter.

[0015] Preferably, the source rock palynological phase analysis data in step S1 includes existing palynological phase data of the study area and / or palynological phase data collected from source rock samples.

[0016] Preferably, the method for acquiring the sporopollen phase data of the source rock sample comprises: subjecting the source rock sample to acid treatment to obtain sporopollen organic matter, and performing transmitted light and fluorescence analysis under a microscope to obtain the sporopollen organic matter data.

[0017] In the present invention, the acid treatment method is a conventional method in the art, for example, using hydrochloric acid and hydrofluoric acid for treatment in sequence.

[0018] Preferably, the saturated hydrocarbon chromatography-mass spectrometry data of source rocks in step S1 include saturated hydrocarbon chromatography-mass spectrometry data of existing source rocks in the study area and / or saturated hydrocarbon chromatography-mass spectrometry data of source rock samples.

[0019] Preferably, the method for acquiring saturated hydrocarbon chromatography-mass spectrometry data from source rock samples comprises: extracting and separating components of source rock samples in sequence to obtain saturated hydrocarbons, and performing chromatography-mass spectrometry analysis on the saturated hydrocarbons.

[0020] Preferably, the condensate oil saturated hydrocarbon chromatography-mass spectrometry data include existing condensate oil saturated hydrocarbon chromatography-mass spectrometry data in the study area and / or saturated hydrocarbon chromatography-mass spectrometry data collected from condensate oil samples.

[0021] Preferably, the method for acquiring chromatography-mass spectrometry data of saturated hydrocarbons collected from the condensate oil sample comprises: separating the components of the condensate oil sample to obtain saturated hydrocarbons, and performing chromatography-mass spectrometry analysis on the saturated hydrocarbons.

[0022] Preferably, the natural gas light hydrocarbon chromatographic data in step S1 include existing natural gas light hydrocarbon chromatographic data in the study area and / or light hydrocarbon chromatographic data collected from natural gas samples.

[0023] Preferably, the method for determining the boundary value of source rock division in step S2 includes: determining the type and content ratio of each palynological phase component in different types of source rocks according to palynological phase analysis data, comparing the content ratio data, and determining the boundary value of source rock division based on the content of palynological phase components.

[0024] Preferably, the types of the sporopollenic components include any one of coal components, wood components, grass components or amorphous components, or a combination of at least two of them.

[0025] Preferably, the method for obtaining the source indicator parameters of the biomarker compounds corresponding to the source rock in step S3 includes: calculating the parameters using the integrated area of ​​the biomarker compounds based on the saturated hydrocarbon chromatography-mass spectrometry data of the source rock.

[0026] Preferably, the biogenic indicator parameters of the biomarker compounds corresponding to the source rock include any one of steranes C27 / C29, Pr / Ph, Ts / Tm or gammacerane / C30 hopane, or a combination of at least two thereof.

[0027] Preferably, the method for acquiring the source indicator parameters of the biomarker compounds corresponding to the condensate oil comprises: calculating and obtaining the parameters using the integrated area of ​​the biomarker compounds according to the saturated hydrocarbon chromatography-mass spectrometry data of the condensate oil.

[0028] Preferably, the biogenic indicator parameters of the biomarker compounds corresponding to the condensate oil include any one of sterane C27 / C29, Pr / Ph, Ts / Tm or gammacerane / C30 hopane, or a combination of at least two thereof.

[0029] In the present invention, sterane C27 / C29, Pr / Ph, Ts / Tm or gammacerane / C30 hopane are all conventional biomarker compound source indicator parameters in the art. Specifically, the sterane C27 / C29 refers to the ratio of the content of 5α(H), 14α(H), 17α(H)-C27(20R) sterane to 24-ethyl-5α(H), 14α(H), 17α(H)-C29 sterane (20R) compounds in the chromatography-mass spectrometry data of the compound with a charge-to-mass ratio of 2:17 in the condensate oil; Pr / Ph refers to the ratio of the contents of pristane and phytane compounds in the chromatogram of saturated hydrocarbons; Ts / Tm refers to the ratio of the contents of 18α(H)-22,29,30-trinorhopane to 17α(H)-22,29,30-trinorhopane in the chromatography-mass spectrometry data of compounds with a mass-to-charge ratio of 191 in condensate oil; Gammacerane / C30 Hopane refers to the ratio of the contents of gammacerane to 17α(H), 21β(H)-C30 Hopane in the chromatography-mass spectrometry data of compounds with a mass-to-charge ratio of 191 in condensate oil.

[0030] Preferably, the method for determining the boundary value of the biogenic indicator parameter in step S3 includes: drawing an intersection diagram according to the content of palynological phase components and the biogenic indicator parameters, and determining the boundary value of the biogenic indicator parameter of the biomarker compound corresponding to the source rock according to the boundary value of the source rock division based on the content of palynological phase components, and the boundary value of the biogenic indicator parameter of the biomarker compound corresponding to the condensate oil is consistent with the boundary value of the biogenic indicator parameter of the biomarker compound corresponding to the source rock.

[0031] In the present invention, the main idea of ​​determining the limit value of the source indicator parameter is: the type of source rock is determined by organic matter, and organic matter is directly composed of sedimentary organic matter formed by biological organic matter under geological action. The content of sporophase components is the most intuitive parameter indicating the composition of biological organic matter. The source indicator parameters determined by the relationship between sporophase components and biomarker compound parameters can avoid the ambiguity of empirical source indicator parameters. The source indicator parameters of source rocks and condensate oil formed by this method can more accurately indicate the type of source rocks.

[0032] Preferably, the method for acquiring the natural gas light hydrocarbon parameters in step S4 includes: calculating the parameters based on the natural gas light hydrocarbon chromatographic data using the integrated area of ​​typical compounds, wherein the typical compounds include methylcyclohexane, toluene and benzene.

[0033] Preferably, the natural gas light hydrocarbon parameters include methylcyclohexane index and toluene / benzene.

[0034] In the present invention, the methylcyclohexane index and toluene / benzene are both conventional natural gas light hydrocarbon parameters in the art. Specifically, the methylcyclohexane index refers to the content ratio of methylcyclohexane / (methylcyclohexane+dimethylcyclopentane+n-heptane) in the natural gas light hydrocarbon chromatogram, multiplied by 100%; toluene / benzene refers to the ratio of the content of toluene to benzene compounds in the natural gas light hydrocarbon chromatogram.

[0035] Preferably, the method for determining the limit value of the natural gas light hydrocarbon parameter includes: drawing an intersection diagram based on the source indicator parameters of the biomarker compounds corresponding to the condensate oil and the natural gas light hydrocarbon parameters, and determining the limit value of the natural gas light hydrocarbon parameter based on the limit value of the source indicator parameters of the biomarker compounds corresponding to the condensate oil.

[0036] In the present invention, the main idea for determining the limit values ​​of natural gas light hydrocarbon parameters is that natural gas and its associated condensate oil are generated simultaneously from source rocks in the condensate oil gas-wet gas stage and are the same hydrocarbon-forming parent materials. Based on this homology, the established relationship between condensate oil and natural gas light hydrocarbons can determine the limit values ​​of natural gas light hydrocarbon parameters.

[0037] Preferably, the identification method further comprises step S6: determining the source rock type of the well to be measured according to the position where the natural gas light hydrocarbon parameter of the well to be measured falls into the intersection diagram of step S5.

[0038] In a second aspect, the present invention provides a device for identifying the type of source rock in an offshore marine-continental transitional facies with few wells, the identification device being used in the method for identifying the type of source rock in an offshore marine-continental transitional facies with few wells described in the first aspect of the present invention, the identification device comprising:

[0039] The acquisition module is used to obtain the sporophase analysis data of source rocks, the chromatography-mass spectrometry data of saturated hydrocarbons of source rocks, the chromatography-mass spectrometry data of saturated hydrocarbons of condensate oil, and the chromatography data of light hydrocarbons of natural gas in the study area;

[0040] A sporo-pollen phase component content calculation module is used to determine the boundary value of source rock division based on the sporo-pollen phase component content according to the sporo-pollen phase analysis data;

[0041] A source indicator parameter calculation module is used to determine the boundary value of the source indicator parameter of the biomarker compound corresponding to the source rock and the condensate oil according to the source rock division boundary value based on the content of the sporofacies component;

[0042] A natural gas light hydrocarbon parameter calculation module is used to determine the limit value of the natural gas light hydrocarbon parameter according to the limit value of the source indicator parameter of the biomarker compound corresponding to the condensate oil;

[0043] The hydrocarbon source rock intersection diagram division module is used to draw the intersection diagram according to the natural gas light hydrocarbon parameters, and divide the corresponding ranges of different types of hydrocarbon source rocks according to the limit values ​​of the natural gas light hydrocarbon parameters.

[0044] Preferably, the identification device further comprises an identification module for determining the source rock type of the well to be measured according to the position where the natural gas light hydrocarbon parameter of the well to be measured falls into the intersection diagram.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] In the identification method provided by the present invention, the biomarker compound corresponding to the sporophase of the source rock, the saturated hydrocarbons of the source rock and the saturated hydrocarbons of the condensate oil is used to clarify the biomarker compound boundary values ​​of the source rock and the natural gas light hydrocarbon parameter boundary values, draw a natural gas light hydrocarbon parameter intersection diagram, and divide the ranges corresponding to the different types of source rocks according to the boundary values ​​of the natural gas light hydrocarbon parameters, thereby providing key information for the evaluation of source rocks and the calculation of oil and gas resources in oil and gas basins, significantly improving the accuracy of identifying source rock types in offshore marine-continental transitional phase sedimentary environments with few wells, and solving the problem of limited samples in areas with few wells. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 is a flow chart of the identification method provided by Embodiment 1 and Embodiment 2 of the present invention;

[0048] Figure 2 is a diagram of the types and contents of the components of the source rock sporopollen phase in Example 2 of the present invention;

[0049] Figure 3 is the chromatographic-mass spectrometric data of the tidal flat-lagoon source rock in Example 2 of the present invention, wherein (a) is the chromatographic-mass spectrometric data of a compound with a mass-to-charge ratio of 217, and (b) is the chromatographic-mass spectrometric data of a compound with a mass-to-charge ratio of 191;

[0050] Figure 4 is the chromatographic-mass spectrometric data of the delta-swamp source rock in Example 2 of the present invention, wherein (a) is the chromatographic-mass spectrometric data of a compound with a mass-to-charge ratio of 217, and (b) is the chromatographic-mass spectrometric data of a compound with a mass-to-charge ratio of 191;

[0051] Figure 5 It is an intersection diagram of the coal component content and the source indicator parameter sterane C27 / C29 in Example 2 of the present invention;

[0052] Figure 6 It is an intersection diagram of the coal quality component content and the source indicator parameter gammacerane / C30 hopane in Example 2 of the present invention;

[0053] Figure 7 is the intersection diagram of sterane C27 / C29 and methylcyclohexane index in Example 2 of the present invention;

[0054] Figure 8 is the intersection diagram of sterane C27 / C29 and toluene / benzene in Example 2 of the present invention;

[0055] Fig. 9 is a cross-plot of natural gas light hydrocarbon parameters in Example 2 of the present invention;

[0056] Fig.10 It is a schematic diagram of the structure of the identification device provided in Example 3 of the present invention. DETAILED DESCRIPTION

[0057] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0058] Example 1

[0059] The present embodiment provides a method for identifying source rock types in offshore marine-continental transitional facies with few wells. The identification method comprehensively utilizes palynological phase analysis data, biomarker compound parameters, and natural gas light hydrocarbon parameters to identify source rock types in offshore marine-continental transitional facies with few wells. The identification method can be performed by an identification device for source rock types in offshore marine-continental transitional facies with few wells, and the identification device can be implemented in the form of hardware and / or software.

[0060] like Figure 1 As shown, the identification method provided in this embodiment includes:

[0061] S1, obtain the palynological data of source rocks, saturated hydrocarbon chromatography-mass spectrometry data of source rocks, saturated hydrocarbon chromatography-mass spectrometry data of condensate oil and chromatographic data of light hydrocarbons of natural gas in the study area;

[0062] In step S1, the pollen phase analysis data of the source rock includes the existing pollen phase data of the study area and / or the pollen phase data of the source rock sample collection, and the method for obtaining the pollen phase data of the source rock sample collection includes: subjecting the source rock sample to acid treatment to obtain pollen organic matter, and performing transmitted light and fluorescence analysis under a microscope to obtain pollen organic matter data;

[0063] In step S1, the saturated hydrocarbon chromatography-mass spectrometry data of source rocks include the saturated hydrocarbon chromatography-mass spectrometry data of existing source rocks in the study area and / or the saturated hydrocarbon chromatography-mass spectrometry data of source rock samples, and the method for obtaining the saturated hydrocarbon chromatography-mass spectrometry data of source rock samples includes: extracting and separating components of source rock samples in sequence to obtain saturated hydrocarbons, and performing chromatography-mass spectrometry analysis on the saturated hydrocarbons;

[0064] In step S1, the saturated hydrocarbon chromatography-mass spectrometry data of condensate oil includes the existing saturated hydrocarbon chromatography-mass spectrometry data of condensate oil in the study area and / or the saturated hydrocarbon chromatography-mass spectrometry data collected from condensate oil samples. The method for acquiring the saturated hydrocarbon chromatography-mass spectrometry data collected from condensate oil samples includes: separating the components of the condensate oil sample to obtain saturated hydrocarbons, and performing chromatography-mass spectrometry analysis on the saturated hydrocarbons;

[0065] In step S1, the natural gas light hydrocarbon chromatographic data includes existing natural gas light hydrocarbon chromatographic data in the study area and / or light hydrocarbon chromatographic data collected from natural gas samples.

[0066] S2, according to the palynological phase analysis data described in step S1, determining the boundary value of source rock division based on the content of palynological phase components;

[0067] In step S2, the method for determining the boundary value of source rock division includes: determining the type and content ratio of each sporofacies component in different types of source rocks according to sporofacies analysis data, comparing the content ratio data, and determining the boundary value of source rock division based on the content of sporofacies components;

[0068] Specifically, the types of the sporopollenic components include any one of coal components, wood components, grass components or amorphous components, or a combination of at least two of them.

[0069] S3, determining the boundary value of the source rock and the source rock corresponding to the condensate oil according to the source rock classification boundary value based on the content of the sporofacies component in step S2;

[0070] In step S3, the method for obtaining the source indicator parameters of the biomarker compounds corresponding to the source rock includes: calculating the parameters using the integrated area of ​​the biomarker compounds according to the saturated hydrocarbon chromatography-mass spectrometry data of the source rock;

[0071] Specifically, the biogenic indicator parameters of the biomarker compounds corresponding to the source rock include any one or a combination of at least two of sterane C27 / C29, Pr / Ph, Ts / Tm or gammacerane / C30 hopane;

[0072] In step S3, the method for obtaining the source indicator parameters of the biomarker compounds corresponding to the condensate oil includes: calculating and obtaining the parameters using the integrated area of ​​the biomarker compounds according to the saturated hydrocarbon chromatography-mass spectrometry data of the condensate oil;

[0073] Specifically, the biogenic indicator parameters of the biomarker compounds corresponding to the condensate oil include any one or a combination of at least two of sterane C27 / C29, Pr / Ph, Ts / Tm or gammacerane / C30 hopane;

[0074] In step S3, the method for determining the boundary value of the biomarker compound's source indicator parameter includes: drawing an intersection diagram according to the content of palynological phase components and the source indicator parameter, and determining the boundary value of the biomarker compound's source indicator parameter corresponding to the source rock according to the source rock division boundary value based on the palynological phase component content, and the boundary value of the biomarker compound's source indicator parameter corresponding to the condensate oil is consistent with the boundary value of the biomarker compound's source indicator parameter corresponding to the source rock.

[0075] S4, determining the limit value of the natural gas light hydrocarbon parameter according to the limit value of the source indicator parameter of the biomarker compound corresponding to the condensate oil in step S3;

[0076] In step S4, the method for acquiring the parameters of natural gas light hydrocarbons includes: calculating the parameters based on the natural gas light hydrocarbon chromatographic data using the integrated area of ​​typical compounds, wherein the typical compounds include methylcyclohexane, toluene and benzene;

[0077] Specifically, natural gas light hydrocarbon parameters include methylcyclohexane index and toluene / benzene;

[0078] In step S4, the method for determining the limit value of the natural gas light hydrocarbon parameter includes: drawing an intersection diagram based on the source indicator parameters of the biomarker compounds corresponding to the condensate oil and the natural gas light hydrocarbon parameters, and determining the limit value of the natural gas light hydrocarbon parameter based on the limit value of the source indicator parameters of the biomarker compounds corresponding to the condensate oil.

[0079] S5, drawing an intersection diagram according to the natural gas light hydrocarbon parameters, and dividing the ranges corresponding to different types of source rocks according to the limit values ​​of the natural gas light hydrocarbon parameters in step S4.

[0080] S6, determining the source rock type of the well to be tested according to the position where the natural gas light hydrocarbon parameter of the well to be tested falls into the intersection diagram described in step S5.

[0081] Example 2

[0082] This embodiment takes the XH sag in the East China Sea Basin, where offshore marine-continental transitional phase source rocks are widely distributed, as an example to identify the types of source rocks therein in order to further explain the composition of the specific technical solution.

[0083] like Figure 1 As shown, the prediction method provided in this embodiment includes:

[0084] S1, obtain the palynological data of source rocks, saturated hydrocarbon chromatography-mass spectrometry data of source rocks, saturated hydrocarbon chromatography-mass spectrometry data of condensate oil and chromatographic data of light hydrocarbons of natural gas in the study area;

[0085] In this embodiment, the palynological phase analysis data of the source rock includes the existing palynological phase data of the study area, and the palynological organic matter data obtained by treating the source rock samples with hydrochloric acid, hydrofluoric acid, etc., and then classifying and identifying the palynological organic matter under a microscope through transmitted light and fluorescence. Specifically, this embodiment collects and supplements the palynological phase analysis data of 30 source rock samples from wells such as XH-3, and the sample wells cover the slope zone with more drilling to the depression zone with less drilling.

[0086] In this embodiment, the saturated hydrocarbon chromatography-mass spectrometry data of source rocks include the saturated hydrocarbon chromatography-mass spectrometry data of existing source rocks in the study area, and the data obtained by sequentially extracting soluble organic matter and separating components of source rock samples to obtain saturated hydrocarbons and then conducting chromatography-mass spectrometry analysis; specifically, this embodiment collects and supplements the saturated hydrocarbon chromatography-mass spectrometry data of 30 source rock samples from wells such as XH-3, and the sample wells cover the main hydrocarbon-generating intervals in the XH Sag;

[0087] In this embodiment, the saturated hydrocarbon chromatography-mass spectrometry data of condensate oil includes the existing saturated hydrocarbon chromatography-mass spectrometry data of condensate oil in the study area, and the data obtained by performing chromatography-mass spectrometry analysis after separating the components of the condensate oil sample to obtain saturated hydrocarbons; specifically, this embodiment collects and supplements the saturated hydrocarbon chromatography-mass spectrometry data of 15 condensate oil samples from wells such as XH-7, and the sample wells cover the main structures and layers where oil and gas have been discovered in the XH Sag;

[0088] In this embodiment, the natural gas light hydrocarbon chromatographic data includes the existing natural gas light hydrocarbon chromatographic data in the study area, as well as the data obtained by collecting natural gas samples for light hydrocarbon chromatographic analysis; specifically, this embodiment collects and supplements the testing of 24 natural gas light hydrocarbon chromatographic data from wells such as XH-1, and the sample wells cover the main structures and layers where natural gas has been discovered in the XH Depression.

[0089] S2, according to the palynological phase analysis data described in step S1, determining the boundary value of source rock division based on the content of palynological phase components;

[0090] In this embodiment, according to the palynological phase analysis data, the contents of coal components, wood components, herbaceous components and amorphous components in each well of the two types of source rocks in the slope zone and the near-sag zone are respectively counted, and the content proportion data are compared to determine the boundary value of the source rock division based on the content of palynological phase components; specifically, taking the slope zone source rock (specifically the delta-swamp in this embodiment) as an example, the content of coal components is more than 60%, and 60% is the boundary value of the source rock division based on the content of coal components (the same applies below), and the contents of herbaceous components and amorphous components are less than 30%; taking the near-sag zone source rock as an example (specifically the tidal flat-lagoon in this embodiment), the content of coal components is less than 60%, and the contents of herbaceous components and amorphous components are more than 30%, such as Figure 2 shown.

[0091] S3, determining the boundary value of the source rock and the source rock corresponding to the condensate oil according to the source rock classification boundary value based on the content of the sporofacies component in step S2;

[0092] In this embodiment, based on the saturated hydrocarbon chromatography-mass spectrometry data of the source rock, the biomarker compound's source indicator parameters are calculated using the integrated area of ​​the biomarker compound, including sterane C27 / C29, Pr / Ph, Ts / Tm and gammacerane / C30 hopane; Figure 3 and Figure 4 As shown, Figure 3 (a) and Figure 4 (a) is the chromatographic-mass spectrometric data of a compound with a charge-to-mass ratio of 2.17, used to calculate sterane C27 / C29, Figure 3 (b) and Figure 4 (b) is the chromatography-mass spectrometry data of the compound with a charge-to-mass ratio of 191, used to calculate Ts / Tm;

[0093] In this embodiment, based on the condensate oil saturated hydrocarbon chromatography-mass spectrometry data, the biomarker compound's origin indicator parameters are calculated using the integrated area of ​​the biomarker compound, including sterane C27 / C29, Pr / Ph, Ts / Tm and gammacerane / C30 hopane;

[0094] In this embodiment, an intersection diagram is drawn according to the content of the sporophase components in the slope zone and the near-sag zone and the source indicator parameters of the biomarker compounds, and the limit values ​​of the source indicator parameters of the biomarker compounds corresponding to the source rock are determined according to the source rock division boundary value based on the sporophase component content. The limit values ​​of the source indicator parameters of the biomarker compounds corresponding to the condensate oil are consistent with the limit values ​​of the source indicator parameters of the biomarker compounds corresponding to the source rock. Specifically, in this embodiment, after calculation, the limit value of sterane C27 / C29 in the slope zone and the near-sag zone is 1.2, the limit value of Pr / Ph is 3.0, the limit value of Ts / Tm is 0.6, and the limit value of gamma cerane / C30 hopane is 0.2; taking the determination of the limit values ​​of the source indicator parameters such as sterane C27 / C29 and gamma cerane / C30 hopane as an example, as shown in the following figure: Figure 5-6 As shown in the figure, the limit value of sterane C27 / C29 is determined based on the limit value of the content of the coal components in the source rock ( Figure 5 ) and the limit value of gamma cerane / C30 hopane ( Figure 6 ).

[0095] S4, determining the limit value of the natural gas light hydrocarbon parameter according to the limit value of the source indicator parameter of the biomarker compound corresponding to the condensate oil in step S3;

[0096] In this embodiment, the methylcyclohexane index and toluene / benzene of the natural gas light hydrocarbon parameters are calculated based on the natural gas light hydrocarbon chromatographic data and the integrated area of ​​the typical compounds, and an intersection diagram is drawn based on the source indicator parameters of the biomarker compounds corresponding to the condensate oil and the natural gas light hydrocarbon parameters, and the limit values ​​of the natural gas light hydrocarbon parameters are determined based on the limit values ​​of the source indicator parameters of the biomarker compounds corresponding to the condensate oil; specifically, Figure 7 and Figure 8 As shown, in this embodiment, after calculation, the limit value of the methylcyclohexane index of the slope zone and the depression zone is 60 ( Figure 7 ), the toluene / benzene parameter limit value is 3.0( Figure 8 ).

[0097] S5, draw an intersection diagram based on the natural gas light hydrocarbon parameters, such as Fig. 9 As shown, the ranges corresponding to different types of source rocks are divided according to the limit values ​​of the natural gas light hydrocarbon parameters in step S4.

[0098] S6, determining the source rock type of the well to be tested according to the position where the natural gas light hydrocarbon parameter of the well to be tested falls into the intersection diagram described in step S5.

[0099] In this embodiment, from Fig. 9 It can be seen that the boundary values ​​of the natural gas light hydrocarbon parameters calculated by the aforementioned method divide the intersection diagram into regions. The delta-swamp-method data and tidal flat-lagoon-method data in the figure refer to the natural gas light hydrocarbon parameter data used in the aforementioned steps S4 and S5, the delta-swamp-division result and the tidal flat-lagoon-division result refer to the natural gas light hydrocarbon parameter data of the well to be tested, the method data indicates that the source rock type in the lower left corner is a delta-swamp type source rock, and the source rock type in the upper right corner is a tidal flat-lagoon type source rock. The natural gas light hydrocarbon parameters of the wells to be tested are calculated respectively, and the source rock type is indicated according to the area where the parameters fall.

[0100] Example 3

[0101] This embodiment provides a device for identifying the type of source rock in offshore marine-continental transitional phase with few wells. Fig.10 As shown, the identification device includes: an acquisition module 110, a sporofacies component content calculation module 120, a source indication parameter calculation module 130, a natural gas light hydrocarbon parameter calculation module 140, a source rock intersection diagram division module 150 and an identification module 160. Among them:

[0102] Acquisition module 110, for acquiring the sporofacies analysis data of source rocks, saturated hydrocarbon chromatography-mass spectrometry data of source rocks, saturated hydrocarbon chromatography-mass spectrometry data of condensate oil, and light hydrocarbon chromatography data of natural gas in the study area;

[0103] The sporo-pollen phase component content calculation module 120 is used to determine the boundary value of source rock division based on the sporo-pollen phase component content according to the sporo-pollen phase analysis data;

[0104] The source indicator parameter calculation module 130 is used to determine the boundary value of the source indicator parameter of the biomarker compound corresponding to the source rock and the condensate oil according to the source rock classification boundary value based on the content of the sporofacies component;

[0105] The natural gas light hydrocarbon parameter calculation module 140 is used to determine the limit value of the natural gas light hydrocarbon parameter according to the limit value of the source indicator parameter of the biomarker compound corresponding to the condensate oil;

[0106] The hydrocarbon source rock intersection diagram division module 150 is used to draw an intersection diagram according to the natural gas light hydrocarbon parameters, and divide the ranges corresponding to different types of hydrocarbon source rocks according to the limit values ​​of the natural gas light hydrocarbon parameters;

[0107] The identification module 160 is used to determine the source rock type of the well to be tested according to the position where the natural gas light hydrocarbon parameters of the well to be tested fall into the intersection diagram.

[0108] In the acquisition module 110, the source rock palynological phase analysis data, the source rock saturated hydrocarbon chromatography-mass spectrometry data, the condensate oil saturated hydrocarbon chromatography-mass spectrometry data and the natural gas light hydrocarbon chromatography data each independently include existing data of the study area and sample collection data.

[0109] In the palynological component content calculation module 120, the type of each palynological component in different types of source rocks and their content ratio are determined according to the palynological analysis data, and the content ratio data are compared to determine the boundary value of the source rock division based on the palynological component content. The type of the palynological component includes any one of coal component, wood component, grass component or amorphous component, or a combination of at least two of them.

[0110] In the source indicator parameter calculation module 130, the source indicator parameters are calculated using the integral area of ​​the biomarker compound according to the saturated hydrocarbon chromatography-mass spectrometry data of the source rock, and the source indicator parameters are calculated using the integral area of ​​the biomarker compound according to the saturated hydrocarbon chromatography-mass spectrometry data of the condensate oil. The source indicator parameters include any one of sterane C27 / C29, Pr / Ph, Ts / Tm or gammacerane / C30 hopane or a combination of at least two of them; an intersection diagram is drawn according to the content of sporopollen phase components and the source indicator parameters, and the limit value of the source indicator parameter of the biomarker compound corresponding to the source rock is determined according to the source rock division boundary value based on the sporopollen phase component content, and the limit value of the source indicator parameter of the biomarker compound corresponding to the condensate oil is consistent with the limit value of the source indicator parameter of the biomarker compound corresponding to the source rock.

[0111] In the natural gas light hydrocarbon parameter calculation module 140, the natural gas light hydrocarbon parameters are calculated based on the natural gas light hydrocarbon chromatographic data using the integrated area of ​​typical compounds, the typical compounds including methylcyclohexane, toluene and benzene, and an intersection diagram is drawn based on the source indicator parameters of the biomarker compounds corresponding to the condensate oil and the natural gas light hydrocarbon parameters, and the limit values ​​of the natural gas light hydrocarbon parameters are determined based on the limit values ​​of the source indicator parameters of the biomarker compounds corresponding to the condensate oil.

[0112] The device provided in this embodiment can execute the method for identifying the type of source rocks in the offshore marine-continental transitional phase with few wells provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0113] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for identifying source rock types in offshore marine-continental transitional facies with few wells, characterized in that: The identification method comprises the following steps: S1, obtain the palynological data of source rocks, saturated hydrocarbon chromatography-mass spectrometry data of source rocks, saturated hydrocarbon chromatography-mass spectrometry data of condensate oil and chromatographic data of light hydrocarbons of natural gas in the study area; S2, according to the palynological phase analysis data described in step S1, determining the boundary value of source rock division based on the content of palynological phase components; S3, determining the boundary value of the source rock and the source rock corresponding to the condensate oil according to the source rock classification boundary value based on the content of the sporofacies component in step S2; S4, determining the limit value of the natural gas light hydrocarbon parameter according to the limit value of the source indicator parameter of the biomarker compound corresponding to the condensate oil in step S3; S5, drawing an intersection diagram according to the natural gas light hydrocarbon parameters, and dividing the ranges corresponding to different types of source rocks according to the limit values ​​of the natural gas light hydrocarbon parameters in step S4.

2. The identification method according to claim 1, characterized in that: The source rock palynological phase analysis data in step S1 includes existing palynological phase data in the study area and / or palynological phase data collected from source rock samples; Preferably, the method for acquiring the sporopollen phase data of the source rock sample comprises: subjecting the source rock sample to acid treatment to obtain sporopollen organic matter, and performing transmitted light and fluorescence analysis under a microscope to obtain the sporopollen organic matter data.

3. The identification method according to claim 1 or 2, characterized in that: The saturated hydrocarbon chromatography-mass spectrometry data of the source rock in step S1 includes the saturated hydrocarbon chromatography-mass spectrometry data of the existing source rock in the study area and / or the saturated hydrocarbon chromatography-mass spectrometry data of the source rock sample; Preferably, the method for acquiring saturated hydrocarbon chromatography-mass spectrometry data from source rock samples comprises: extracting and separating components of source rock samples in sequence to obtain saturated hydrocarbons, and performing chromatography-mass spectrometry analysis on the saturated hydrocarbons; Preferably, the condensate oil saturated hydrocarbon chromatography-mass spectrometry data include existing condensate oil saturated hydrocarbon chromatography-mass spectrometry data in the study area and / or condensate oil sample collection saturated hydrocarbon chromatography-mass spectrometry data; Preferably, the method for acquiring chromatography-mass spectrometry data of saturated hydrocarbons collected from the condensate oil sample comprises: separating the components of the condensate oil sample to obtain saturated hydrocarbons, and performing chromatography-mass spectrometry analysis on the saturated hydrocarbons.

4. The identification method according to any one of claims 1 to 3, characterized in that: The natural gas light hydrocarbon chromatographic data in step S1 include existing natural gas light hydrocarbon chromatographic data in the study area and / or light hydrocarbon chromatographic data collected from natural gas samples.

5. The identification method according to any one of claims 1 to 4, characterized in that: The method for determining the boundary value of source rock division in step S2 includes: determining the type and content ratio of each sporofacies component in different types of source rocks according to sporofacies analysis data, comparing the content ratio data, and determining the boundary value of source rock division based on the content of sporofacies components; Preferably, the types of the sporopollenic components include any one of coal components, wood components, grass components or amorphous components, or a combination of at least two of them.

6. The identification method according to any one of claims 1 to 5, characterized in that: The method for obtaining the source indicator parameters of the biomarker compounds corresponding to the source rock in step S3 includes: calculating the parameters using the integrated area of ​​the biomarker compounds according to the saturated hydrocarbon chromatography-mass spectrometry data of the source rock; Preferably, the biogenic indicator parameters of the biomarker compounds corresponding to the source rock include any one or a combination of at least two of sterane C27 / C29, Pr / Ph, Ts / Tm or gammacerane / C30 hopane; Preferably, the method for obtaining the source indicator parameters of the biomarker compounds corresponding to the condensate oil comprises: calculating the parameters using the integrated area of ​​the biomarker compounds according to the saturated hydrocarbon chromatography-mass spectrometry data of the condensate oil; Preferably, the biogenic indicator parameters of the biomarker compounds corresponding to the condensate oil include any one or a combination of at least two of sterane C27 / C29, Pr / Ph, Ts / Tm or gammacerane / C30 hopane; Preferably, the method for determining the boundary value of the biogenic indicator parameter in step S3 includes: drawing an intersection diagram according to the content of palynological phase components and the biogenic indicator parameters, and determining the boundary value of the biogenic indicator parameter of the biomarker compound corresponding to the source rock according to the boundary value of the source rock division based on the content of palynological phase components, and the boundary value of the biogenic indicator parameter of the biomarker compound corresponding to the condensate oil is consistent with the boundary value of the biogenic indicator parameter of the biomarker compound corresponding to the source rock.

7. The identification method according to any one of claims 1 to 6, characterized in that: The method for obtaining the natural gas light hydrocarbon parameters in step S4 includes: calculating the parameters based on the natural gas light hydrocarbon chromatographic data using the integrated area of ​​typical compounds, wherein the typical compounds include methylcyclohexane, toluene and benzene; Preferably, the natural gas light hydrocarbon parameters include methylcyclohexane index and toluene / benzene; Preferably, the method for determining the limit value of the natural gas light hydrocarbon parameter includes: drawing an intersection diagram based on the source indicator parameters of the biomarker compounds corresponding to the condensate oil and the natural gas light hydrocarbon parameters, and determining the limit value of the natural gas light hydrocarbon parameter based on the limit value of the source indicator parameters of the biomarker compounds corresponding to the condensate oil.

8. The identification method according to any one of claims 1 to 7, characterized in that: The identification method further comprises step S6: determining the source rock type of the well to be tested according to the position where the natural gas light hydrocarbon parameter of the well to be tested falls into the intersection diagram of step S5.

9. A device for identifying the type of source rock in offshore marine-continental transitional phase with few wells, characterized in that: The identification device is used in the method for identifying the type of source rock in offshore marine-continental transitional phase with few wells as claimed in any one of claims 1 to 8, and the identification device comprises: The acquisition module is used to obtain the sporophase analysis data of source rocks, the chromatography-mass spectrometry data of saturated hydrocarbons of source rocks, the chromatography-mass spectrometry data of saturated hydrocarbons of condensate oil, and the chromatography data of light hydrocarbons of natural gas in the study area; A sporo-pollen phase component content calculation module is used to determine the boundary value of source rock division based on the sporo-pollen phase component content according to the sporo-pollen phase analysis data; A source indicator parameter calculation module is used to determine the boundary value of the source indicator parameter of the biomarker compound corresponding to the source rock and the condensate oil according to the source rock division boundary value based on the content of the sporofacies component; A natural gas light hydrocarbon parameter calculation module is used to determine the limit value of the natural gas light hydrocarbon parameter according to the limit value of the source indicator parameter of the biomarker compound corresponding to the condensate oil; The hydrocarbon source rock intersection diagram division module is used to draw the intersection diagram according to the natural gas light hydrocarbon parameters, and divide the corresponding ranges of different types of hydrocarbon source rocks according to the limit values ​​of the natural gas light hydrocarbon parameters.

10. The identification device according to claim 9, characterized in that: The identification device further comprises an identification module for determining the type of source rock of the well to be measured according to the position where the natural gas light hydrocarbon parameter of the well to be measured falls into the intersection diagram.

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