Method for tracing magma invasion path and activity intensity based on polycyclic aromatic hydrocarbon

Abstract

The invention discloses a method for tracing a magma invasion path and activity intensity based on polycyclic aromatic hydrocarbon. The method comprises the following steps: S1, selecting a crude oil sample in an active magma region, and detecting polycyclic aromatic hydrocarbon in the crude oil sample and a relative peak area; the polycyclic aromatic hydrocarbon comprises indeno [1, 2, 3-cd] pyrene, benzo [g, h, i] perylene and a halo benzene compound; s2, the ratio of 100 * (A indeno [1, 2, 3-cd] pyrene + A halobenzene) / (A benzo [g, h, i] perylene + A indeno [1, 2, 3-cd] pyrene + A halobenzene) is determined according to the peak area obtained in S1, and the ratio is gt; when the concentration is 25%, the crude oil is subjected to magma baking; s3, drawing a plane contour map of a formula (1); and tracing the magma invasion path and the activity intensity according to the plane contour map. The method and the system for tracing the magma invasion path and indicating the magma activity intensity, which are provided by the invention, are rapid, visual and simple and convenient to operate, and the accuracy of tracing the magma invasion path and indicating the magma activity intensity is greatly improved.

Description

Technical Field

[0001] The present invention relates to a method for tracing magma intrusion paths and activity intensities based on polycyclic aromatic hydrocarbons, and belongs to the technical field of petroleum exploration. Background Art

[0002] Magma, as a high-temperature silicate molten substance rich in volatile components deep underground, usually has a temperature distribution between 800 - 1200 °C. During its upward intrusion from underground, it will bake the surrounding rocks along the way. Since the formation of the basin, multiple stages of magma intrusion events usually occur. Magma intrusion not only has a significant impact on oil and gas resources, but also causes serious troubles to oil and gas development (such as restricting drilling).

[0003] Generally, technical means such as petrological research, seismic observation, and numerical simulation can be used to speculate on the intrusion paths and activity intensities of magma. For example, Fang Weixuan, Guo Yuqian, Li Tiancheng, etc. published "Penetration mechanism of hydrothermal activities in magma-deficient areas of slow - ultraslow spreading centers" in Acta Geologica Sinica, and analyzed the intrusion sequence of intrusive rocks based on large-scale structural lithofacies mapping methods to reveal its activity intensity. Niu Yuemeng, Han Jun, Yu Yixin, etc. published "Development characteristics of igneous intrusions in the Shunbei western region of the Tarim Basin and their coupling relationship with faults" in Oil & Gas Geology, and finely characterized the morphological characteristics of igneous intrusions based on two-dimensional and three-dimensional seismic data to identify the development stages and intrusion channels of igneous intrusions. Fan Qingkai, Cheng Peng, Feng Bo, etc. published "Penetration mechanism of hydrothermal activities in magma-deficient areas of slow - ultraslow spreading centers" in Geotectonica et Metallogenia, and explored the intrusion - heating - cooling - fracture process of deep multi-stage magma intrusions through numerical simulation methods based on the lithosphere cooling - fracture theoretical model. However, the above methods are usually applied to mature exploration blocks, require accurate knowledge of regional geological conditions, have high requirements for time cost and economic cost, and require researchers to have rich experience and a series of problems. Most importantly, there are many influencing factors for the processing results and the accuracy is low.

[0004] Therefore, how to provide a method for quickly, simply and accurately tracing magma intrusion paths and indicating magma activity intensities is an urgent problem to be solved. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for tracing magma intrusion paths and indicating magma activity intensities. The method of the present invention is fast, intuitive and easy to operate, and can greatly improve the speed and accuracy of tracing magma intrusion paths and indicating magma activity intensities.

[0006] The method for tracing magma intrusion paths and activity intensities based on polycyclic aromatic hydrocarbons provided by the present invention includes the following steps:

[0007] S1. Select crude oil samples from areas with magmatic activity, and detect the polycyclic aromatic hydrocarbons and their relative peak areas in the crude oil samples;

[0008] The polycyclic aromatic hydrocarbons include indeno[1,2,3-cd]pyrene, benzo[g,h,i]perylene, and coronene compounds;

[0009] S2. Determine the ratio of formula (1) based on the peak areas obtained in S1. When the ratio > 25%, it indicates that the crude oil has been baked by magma;

[0010] 100×(A 茚并[1,2,3-cd]芘 +A 晕苯 ) / (A 苯并[g,h,i]苝 +A 茚并[1,2,3-cd]芘 +A 晕苯 )(1)

[0011] In the formula, A 茚并[1,2,3-cd]芘 represents the peak area of indeno[1,2,3-cd]pyrene, A 晕苯 represents the peak area of coronene compounds, and A 苯并[g,h,i]苝 represents the peak area of benzo[g,h,i]perylene;

[0012] S3. Draw a planar contour map of formula (1); the tracing of the magma intrusion path and activity intensity can be realized according to the planar contour map.

[0013] Preferably, in step S1, the polycyclic aromatic hydrocarbons are obtained according to the following steps:

[0014] Perform group component separation on the crude oil sample to obtain a saturated hydrocarbon component, an aromatic hydrocarbon component, a non-hydrocarbon component, and the asphaltene component;

[0015] The steps of the group component separation are as follows: First, dissolve and precipitate the asphaltene with petroleum ether, filter the asphaltene through filter paper to obtain the remaining components after removing the asphaltene; add the remaining components to a chromatography column containing aluminum oxide and silica gel, and rinse successively with petroleum ether, dichloromethane, and a dichloromethane-methanol mixture (93:7) to obtain the saturated hydrocarbon component, the aromatic hydrocarbon component, and the non-hydrocarbon component.

[0016] Preferably, in step S1, the polycyclic aromatic hydrocarbons in the aromatic hydrocarbon component are detected by gas chromatography-mass spectrometry, and the detection conditions are as follows:

[0017] The initial temperature is 50°C, held for 1 min, then raised to 250°C at a rate of 20°C / min, then raised to 310°C at a rate of 20°C / min, and finally held at 310°C for 10 min. The mass spectrometer operates in the selected ion monitoring mode with electron ionization of 70 eV.

[0018] Preferably, in step S1, the peak areas of the polycyclic aromatic hydrocarbons are determined according to the following method:

[0019] Manually integrate on compound analysis software (such as MSD ChemStation), select the ion signal as DATASIM.MS, extract the ion chromatogram, input ion 276, identify and authenticate indeno[1,2,3-cd]pyrene and benzo[g,h,i]perylene, and manually integrate to complete the calculation of the peak areas of indeno[1,2,3-cd]pyrene and benzo[g,h,i]perylene. Then extract the ion chromatogram, input ion 300, identify and authenticate coronene compounds, and manually integrate to complete the calculation of the peak areas of coronene compounds.

[0020] Preferably, in step S3, draw the plane isogram in combination with the distribution characteristics of the magma intrusion body.

[0021] Preferably, in step S3, trace the magma intrusion path and activity intensity according to the following principles:

[0022] The magma surges upward along the fracture and starts to intrude along the layer when it encounters fine-grained sediments. The higher the ratio of formula (1), the stronger the influence of the magma on the crude oil. Therefore, the highest value of the ratio of formula (1) can indicate the initial intrusion point of the magma, and the decreasing ratio indicates the intrusion path of the magma.

[0023] Based on the method of the present invention, the present invention also provides a system for tracing the magma intrusion path and activity intensity based on polycyclic aromatic hydrocarbons, including:

[0024] A pretreatment module; the pretreatment module processes the crude oil sample to obtain the polycyclic aromatic hydrocarbons;

[0025] An analysis and detection module; the analysis and detection module detects the polycyclic aromatic hydrocarbons to obtain the peak areas of indeno[1,2,3-cd]pyrene, benzo[g,h,i]perylene and coronene compounds;

[0026] A data processing module; the data processing module calculates the ratio of formula (1) of the crude oil sample and draws the plane isogram.

[0027] The present invention has the following beneficial technical effects:

[0028] The present invention provides a method and system for quickly, intuitively and simply tracing the magma intrusion path and indicating the magma activity intensity, which greatly improves the accuracy of tracing the magma intrusion path and indicating the magma activity intensity. Description of the Drawings

[0029] Figure 1 It is the identification and authentication results of indeno[1,2,3-cd]pyrene, benzo[g,h,i]perylene and coronene compounds in the crude oil sample in the Shunbei area in Example 1.

[0030] Figure 2 To identify the intensity of magmatic activity using the ternary diagram of indeno[1,2,3-cd]pyrene, benzo[g,h,i]perylene, and coronene in the Paleozoic of the Shunbei area in Example 1.

[0031] Figure 3 For the planar distribution range and characteristics of igneous intrusions in the Paleozoic of the Shunbei area in Example 1.

[0032] Figure 4 To trace the magmatic intrusion path and indicate the intensity of magmatic activity by using the isogram drawn in combination with the distribution range of igneous intrusions in Example 1.

[0033] Figure 5 For the seismic profile of the F8 fault zone and the identification results of magmatic intrusion in Example 1. Specific implementation mode

[0034] The following non-limiting examples can enable those of ordinary skill in the art to understand the present invention more comprehensively, but do not limit the present invention in any way. The following content is merely an exemplary illustration of the scope claimed by the present invention. Those skilled in the art can make various changes and modifications to the invention of the present invention based on the disclosed content, and it should also fall within the scope claimed by the present invention.

[0035] When numerical ranges are given in the examples, it should be understood that unless otherwise specified in the present invention, both endpoints of each numerical range and any value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those skilled in the technical field of the present invention. In addition to the specific methods, devices, and materials used in the examples, according to the knowledge of those skilled in the art of the present technology and the description of the present invention, any methods, devices, and materials similar to or equivalent to the methods, devices, and materials described in the embodiments of the present invention can also be used to implement the present invention.

[0036] The present invention will be further described below by way of specific examples. All kinds of chemical reagents used in the embodiments of the present invention are obtained through conventional commercial channels unless otherwise specified.

[0037] Example 1

[0038] Trace the magmatic intrusion path and the intensity of magmatic activity for 36 crude oil samples in the Shunbei area

[0039] Step S1: Weigh 30 - 40 mg of crude oil samples with diabase rock body distribution in the Shunbei area for group component separation to obtain saturated hydrocarbon components, aromatic hydrocarbon components, non-hydrocarbon components, and asphaltene components;

[0040] Family component separation method: First, dissolve and precipitate asphaltenes with petroleum ether, filter the asphaltenes through filter paper to obtain the remaining components after removing asphaltenes; add the remaining components to a chromatography column containing aluminum oxide and silica gel, and rinse successively with petroleum ether, dichloromethane, and dichloromethane + methanol (93:7) to obtain saturated hydrocarbon components, aromatic hydrocarbon components, and non-hydrocarbon components successively.

[0041] Dilute the obtained aromatic hydrocarbon components with 0.2 mL of dichloromethane, then transfer them to a sample injection vial and perform chromatographic-mass spectrometric analysis in a gas chromatography-mass spectrometry (GC-MS) instrument;

[0042] GC-MS analysis conditions: The initial temperature is 50 °C, hold for 1 min, then increase the temperature to 250 °C at a rate of 20 °C / min, then increase the temperature to 310 °C at a rate of 20 °C / min, and finally hold at 310 °C for 10 min. The mass spectrometer operates with electron ionization at 70 eV in the selected ion monitoring mode.

[0043] Perform identification, recognition, and manual integration on a compound analysis software (e.g., MSD ChemStation) ( Figure 1 ).

[0044] Compound identification, recognition, and manual integration method: Select the ion signal as DATASIM.MS, extract the ion chromatogram, input the ion 276, identify and authenticate indeno[1,2,3-cd]pyrene and benzo[g,h,i]perylene, and then manually integrate to complete the calculation of the peak areas of indeno[1,2,3-cd]pyrene and benzo[g,h,i]perylene. Extract the ion chromatogram, input the ion 300, identify and authenticate coronene, and then manually integrate to complete the calculation of the peak area of coronene ( Figure 1 ).

[0045] Step S2: Calculate the ratio of 100×(indeno[1,2,3-cd]pyrene + coronene) / (benzo[g,h,i]perylene + indeno[1,2,3-cd]pyrene + coronene) based on the integrated peak area results. Figure 2 It is shown that there are obvious differences in the distribution characteristics of crude oil samples with igneous rock intrusion and affected by magma intrusion in the triangular diagram compared with those without igneous rock intrusion and not affected by magma intrusion. And according to the calculation result of the ratio of 100×(A 茚并[1,2,3-cd]芘 +A 晕苯 ) / (A 苯并[g,h,i]苝 +A 茚并[1,2,3-cd]芘 +A 晕苯 ), it is found that when the ratio is equal to 25%, it should be the boundary value for distinguishing the two types of samples, that is, when the ratio > 25%, it indicates that the crude oil has been baked by magma.

[0046] Calculate 100×(A 茚并[1,2,3-cd]芘 +A晕苯 ) / (A 苯并[g,h,i]苝 +A 茚并[1,2,3-cd]芘 +A 晕苯 ) ratio. In this embodiment, A1 is 31.59, A2 is 30.08, A3 is 25.48, A4 is 25.00, B1 is 26.10, C1 is 42.16, C2 is 38.30, C3 is 50.84, C4 is 31.48, C5 is 25.99, C6 is 21.25, C7 is 31.48, C8 is 17.48, C9 is 17.46, C10 is 31.41, D1 is 48.28, D2 is 29.05, D3 is 55.62, D4 is 24.77, D5 is 15.95, D6 is 20.03, E1 is 34.10, E2 is 31.48, F1 is 35.34, G1 is 27.81, G2 is 35.91, G3 is 43.55, G4 is 46.42, G5 is 47.90, G6 is 16.82, G7 is 11.07, G8 is 40.48, H1 is 30.58, I1 is 28.48, J1 is 47.89.

[0047] Step S3: Combine the distribution characteristics of the magma intrusion body ( Figure 3 ) to draw an isogram of the ratio of 100×(A 茚并[1,2,3-cd]芘 +A 晕苯 ) / (A 苯并[g,h,i]苝 +A 茚并[1,2,3-cd]芘 +A 晕苯 ) ( Figure 4 ).

[0048] Step S4: The magma surges upward along the fault and starts to intrude along the bedding when it meets fine-grained sediments. The higher the ratio of 100×(indeno[1,2,3-cd]pyrene + coronene) / (benzo[g,h,i]perylene + indeno[1,2,3-cd]pyrene + coronene) indicates that the crude oil is more strongly affected by the magma. Therefore, the highest value of 100×(indeno[1,2,3-cd]pyrene + coronene) / (benzo[g,h,i]perylene + indeno[1,2,3-cd]pyrene + coronene) can indicate the initial intrusion point of the magma, and the decreasing ratio indicates the intrusion path of the magma. The results are as Figure 4 shown. There are 1-2 high points of the ratio of 100×(A 茚并[1,2,3-cd]芘 +A 晕苯 ) / (A 苯并[g,h,i]苝 +A 茚并[1,2,3-cd]芘 +A 晕苯 ) in each magma intrusion body. Figure 4 Several high points of the ratio in

[0049] The results show that the method of the present invention can quickly trace the magma intrusion path and indicate the intensity of magma activity. The seismic profile of the F8 fault zone shows that the positions where Wells G3 and G8 are located are indeed closest to the initial point of magma intrusion ( Figure 5 ). This result confirms that the identification result of the method of the present invention is highly accurate and can be widely promoted.

[0050] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than limiting the protection scope of the present invention. Any simple modification or equivalent replacement made by those of ordinary skill in the art to the technical solution of the present invention shall not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A method for tracing the path and activity intensity of magma intrusion based on polycyclic aromatic hydrocarbons, comprising the following steps: S1. Select crude oil samples from areas with active magma, and detect polycyclic aromatic hydrocarbons in the crude oil samples and the peak areas thereof; The polycyclic aromatic hydrocarbons include indeno[1,2,3-cd]pyrene, benzo[g,h,i]perylene and coronene compounds; S2, determining the ratio of formula (1) according to the peak area obtained in S1, when the ratio is greater than 25%, it indicates that the crude oil has been baked by magma; 100×(A 茚并[1,2,3-cd]芘 +A 晕苯 ) / (A 苯并[g,h,i]苝 +A 茚并[1,2,3-cd]芘 +A 晕苯 )(1) In the formula, A 茚并[1,2,3-cd]芘 represents the peak area of ​​indeno[1,2,3-cd]pyrene, A 晕苯 represents the peak area of ​​coronene compounds, A 苯并[g,h,i]苝 represents the peak area of ​​benzo[g,h,i]perylene; S3, drawing a plane contour map of formula (1); tracing the magma intrusion path and activity intensity based on the plane contour map.

2. The method according to claim 1, characterized in that: In step S1, the polycyclic aromatic hydrocarbons are obtained according to the following steps: Separating the crude oil sample into group components to obtain saturated hydrocarbon components, aromatic hydrocarbon components, non-hydrocarbon components and the asphaltene component; The steps of separating the group components are: using petroleum ether to dissolve and precipitate asphaltene, filtering the asphaltene through filter paper to obtain the remaining components after removing the asphaltene; adding the remaining components to a chromatography column, washing them with petroleum ether, dichloromethane, and a dichloromethane-methanol mixture in sequence, and successively obtaining the saturated hydrocarbon component, the aromatic hydrocarbon component, and the non-hydrocarbon component.

3. The method according to claim 1 or 2, characterized in that: In step S1, the polycyclic aromatic hydrocarbons are detected by gas chromatography-mass spectrometry, and the detection conditions are as follows: The initial temperature was 50 °C, maintained for 1 min, then increased to 250 °C at a rate of 20 °C / min, then increased to 310 °C at a rate of 20 °C / min, and finally maintained at 310 °C for 10 min. The mass spectrometer was operated with electron ionization at 70 eV in the selected ion monitoring mode.

4. The method according to any one of claims 1 to 3, characterized in that: In step S1, the peak area of ​​the polycyclic aromatic hydrocarbons is determined according to the following method: Manual integration was performed on the compound analysis software, the ion signal was selected as DATASIM.MS, the ion chromatogram was extracted, and ion 276 was input. Indeno[1,2,3-cd]pyrene and benzo[g,h,i]perylene were identified and qualified, and the peak area calculation of indeno[1,2,3-cd]pyrene and benzo[g,h,i]perylene was completed by manual integration. The ion chromatogram was extracted, ion 300 was input, the coronene compounds were identified and qualified, and the peak area calculation of the coronene compounds was completed by manual integration.

5. The method according to any one of claims 1 to 4, characterized in that: In step S3, the plane contour map is drawn in combination with the distribution characteristics of the magma intrusion body.

6. The method according to any one of claims 1 to 5, characterized in that: In step S3, the magma intrusion path and activity intensity are traced according to the following principles: The magma rises along the fault and begins to invade along the layer when it encounters fine-grained sediments. The higher the ratio of formula (1), the stronger the impact of magma on the crude oil. Therefore, the highest value of the ratio of formula (1) can indicate the initial invasion point of magma, and the decrease of the ratio indicates the path of magma invasion.

7. A system for tracing the path and activity intensity of magma intrusion based on polycyclic aromatic hydrocarbons, comprising: Pre-processing module; The pre-processing module processes the crude oil sample to obtain the polycyclic aromatic hydrocarbons; An analysis and detection module; the analysis and detection module detects the polycyclic aromatic hydrocarbons to obtain the peak areas of indeno[1,2,3-cd]pyrene, benzo[g,h,i]perylene and coronene compounds; Data processing module; the data processing module calculates the ratio of formula (1) of the crude oil sample and draws the plane contour map.

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