A fast seismic interpretation method based on formation trends

Abstract

The present invention discloses a rapid seismic interpretation method based on formation trends, including steps such as seismic pre-interpretation, determination of zonal interpretation, preliminary interpretation using the formation trend method, generation of a preliminary depth map, intersection closure interpretation, interpretation of areas within high-risk polygons, precise tracking of the interpreted formation, and other formation interpretations; during specific interpretation, first interpret low-risk areas and then high-risk areas. Following the interpretation idea of starting from the easy ones and then dealing with the difficult ones, through a series of technical methods such as seismic pre-interpretation, zonal interpretation, and trend interpretation, the interpretation efficiency is effectively improved, good results are achieved in practice, and at the same time, the interpretation time is greatly compressed, having broad reference and popularization value.

Description

Technical Field

[0001] The present invention belongs to the field of marine seismic data interpretation, and particularly relates to a fast seismic interpretation method based on formation trend. Background Art

[0002] Seismic interpretation generally refers to structural interpretation, which mainly determines the outline and structural characteristics of geological bodies. For large-scale high-resolution marine engineering exploration projects, the time span often spans a period of 5 - 10 years. Due to different exploration purposes and tasks in different years, different exploration equipment is used, and there are significant differences in the types of high-resolution seismic data collected in different years. When these different types of seismic data are uniformly subjected to seismic interpretation, the difficulty increases exponentially compared to single-type seismic data.

[0003] Traditional interpretation methods, such as the method of first interpreting faults and then horizons, are difficult to apply to this kind of high-resolution seismic data. The main reasons are that the detection depth of the high-resolution seismic data profile is shallow, it is difficult to determine the controlling faults, and at the same time, there are too many shallow faults and it is difficult to accurately classify them, resulting in the ineffectiveness of traditional methods. In addition, the seismic data of this kind of project is often very large. According to the conventional interpretation method, a project often requires half a year or even longer, and the interpretation efficiency is too low. Summary of the Invention

[0004] In order to solve the defects such as low interpretation efficiency in the prior art according to the conventional interpretation method, the present invention proposes a fast seismic interpretation method based on formation trend to effectively improve the interpretation efficiency.

[0005] The present invention is implemented by adopting the following technical solutions: A fast seismic interpretation method based on formation trend, comprising the following steps:

[0006] Step A, seismic pre-interpretation: including the determination of the formation trend of the main survey line and the connecting survey line, the selection of the control survey line, and the division of high-risk survey lines, and generating a seismic pre-interpretation result map;

[0007] Step B, determination of zonal interpretation, further clarifying the distribution range of the high-risk area according to the seismic pre-interpretation result map, and interpreting horizons based on the formation trend:

[0008] Step B1, first interpret the low-risk area outside the high-risk area;

[0009] Step B11, perform preliminary interpretation using the formation trend method: make a trend interpretation of the interpreted horizons without paying attention to specific details, only make accurate interpretations near the intersections of the survey lines, and use the closure of the survey lines as the final quality evaluation criterion to complete the interpretation of the main survey line and the connecting survey line;

[0010] Step B12. Generate a preliminary depth map: After the main survey line and connection survey line are interpreted, generate a preliminary depth map, and mark the areas where the intersections are not closed and the fault areas to provide a reference for the next intersection closure interpretation;

[0011] Step B13. Intersection closure interpretation: Continuously adjust the horizons based on the intersection closure principle to conform to the geological structure law;

[0012] Step B2. Interpret the high-risk areas: Follow the idea of Step B1 and repeat Steps B11 - B13 to complete the interpretation of the high-risk areas;

[0013] Step C. Precise tracing of the interpreted strata: After the horizon interpretation is completed, conduct precise tracing of the interpreted horizons;

[0014] Step D. According to the interpretation ideas of Steps A - C, complete the interpretation of key horizons, basement interpretation, and other secondary horizon interpretations.

[0015] Furthermore, the specific method for Step A is as follows:

[0016] Step A1. First, compare the main survey lines to determine the trend of the strata in the main structural direction in the work area: By comparing the stratigraphic strikes of the main survey line and the strata on both sides, if the survey line density is large, select the control survey lines, and determine the stratigraphic strike through the control survey lines;

[0017] Step A2. Then, determine the stratigraphic strike of the connection survey lines according to the same idea as in Step A1;

[0018] Step A3. Divide the high-risk survey lines based on shallow gas, imaging fuzzy areas, etc.

[0019] Furthermore, in Step B, when conducting zonal interpretation:

[0020] If the distribution range of the high-risk survey lines is small, they are directly involved in the interpretation work without zoning, but attention should be paid to the high-risk survey lines during the interpretation;

[0021] If the distribution range of the high-risk survey lines is concentrated in a certain area and is distributed in a grid pattern, the high-risk area should be divided, and this area should be excluded during the interpretation, that is, wait until the interpretation of other areas is completed and then conduct the interpretation of this high-risk area.

[0022] Furthermore, in Step B11, when conducting preliminary interpretation, it is specifically as follows:

[0023] Step (1): First, conduct a trend interpretation of the main survey line: Interpret according to the stratigraphic trend, and only mark the stratigraphic strike. For the areas near the intersections of the survey lines, conduct precise interpretation, that is, interpret along the isophase axis, and complete the interpretation of the remaining main survey lines according to the same plan;

[0024] Step (2): After the main survey line interpretation is completed, the connection survey line shows the interpretation points of the main survey line. If the interpretation plan is correct, connecting each interpretation point completes the interpretation of the connection survey line.

[0025] Furthermore, after connecting each interpretation point in step (2), the following situations may occur:

[0026] 1) The interpretation points switch back and forth between multiple sets of strata. In this case, precise interpretation is not required. Only the middle stratum needs to be found according to the principle of linear regression for trend stratum interpretation.

[0027] 2) There is an obvious deviation between a certain interpretation point and other interpretation points. Excluding the possibility of a drastic change in the stratum structure, interpolation interpretation is relied on other points at this time, and then the corresponding interpretation points on the main survey line are corrected.

[0028] 3) The interpretation points are concentrated between two sets of horizons. At this time, it is necessary to first determine whether there is a fault near the conversion point:

[0029] If there is a fault and the stratum strike conforms to the objective law, it indicates that the interpretation is correct, and the fault and its strike are marked on the seismic pre-interpretation result map.

[0030] If there is no fault and there is no drilling control or other index control, it should be processed according to the principle of simplification, that is, the simpler interpretation plan is adopted, and the selected stratum strike is described in the interpretation plan. In addition, it should be noted that if the distance between the two sets of strata is far, an additional set of interpretation horizons can also be considered.

[0031] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0032] This solution proposes to interpret such seismic data according to the stratum trend. According to the interpretation idea of starting from the easy and then dealing with the difficult, a series of technical methods such as seismic pre-interpretation, zonal interpretation, and trend interpretation are used to effectively improve the interpretation efficiency, achieving good results in practice, and at the same time greatly shortening the interpretation time, which has important reference significance for some large-scale or long-span projects and has wide reference and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a flow chart of the fast seismic interpretation method described in the embodiment of the present invention;

[0034] Figure 2 It is the seismic pre-interpretation result map described in the embodiment of the present invention, where the black line is marked as the high-risk survey line;

[0035] Figure 3 It is a schematic diagram of the quality difference of seismic profiles collected by different devices in the embodiment of the present invention;

[0036] Figure 4 Schematic diagram of a typical seismic pre - interpretation survey line for the embodiments of the present invention;

[0037] Figure 5 Schematic diagram of the division of high - risk areas and non - control survey lines in seismic interpretation for the embodiments of the present invention;

[0038] Figure 6 Schematic diagram of preliminary interpretation using formation trends for the embodiments of the present invention;

[0039] Figure 7 Schematic diagram of the preliminary depth map generated for the embodiments of the present invention;

[0040] Figure 8 Schematic diagram of the interpretation results of typical survey lines in the work area for the embodiments of the present invention. Detailed implementation manners

[0041] In order to more clearly understand the above - mentioned objects, features and advantages of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0042] This embodiment proposes a fast seismic interpretation method based on formation trends, and its basic idea is as follows:

[0043] Step A, seismic pre - interpretation: including the determination of formation trends of main survey lines and connecting survey lines, the selection of control survey lines, and the division of high - risk survey lines, and generating a seismic pre - interpretation result map;

[0044] Step B, determination of zonal interpretation: clarify the distribution range of difficult areas and interpret horizons based on the formation trend method;

[0045] Step B1, first interpret the low - risk areas outside the high - risk areas. The high - risk areas are also called difficult interpretation areas:

[0046] Step B11, perform preliminary interpretation using the formation trend method: make a trend interpretation of the horizons to be interpreted without focusing on specific details, and only make a fine interpretation near the intersections of survey lines, and use the closed points of the survey lines as the final quality evaluation criteria;

[0047] Step B12, generate a preliminary depth map: generate a preliminary depth map after the interpretation of main survey lines and connecting survey lines, and mark areas where intersections are not closed and faults, etc., to provide a reference for the next intersection closure interpretation;

[0048] Step B13, Explanation of intersection closure: Repeatedly infer and modify by comprehensively considering factors such as faults, formation trends, and structures, and continuously adjust the horizons to conform to the laws of geological structures.

[0049] Step B2, Explanation of high-risk areas: According to the explanation idea in Step B1, repeat Steps B11 - B13 to complete the regional explanation within the high-risk polygons.

[0050] Step C, Precise tracing of formations.

[0051] Repeat Steps A - C to successively complete tasks such as basement interpretation, key horizon interpretation, and other horizon interpretations.

[0052] As Figure 1 shown, the present invention will be described in detail below in combination with specific operation methods:

[0053] Step 1, Seismic pre-interpretation:

[0054] Seismic pre-interpretation means that no formal interpretation work has started yet, but some preparatory work is done for the formal interpretation. The main work includes determining the formation trends of main survey lines and connecting survey lines, selecting control survey lines, and dividing high-risk survey lines, where high-risk survey lines are divided based on shallow gas, imaging blurred areas, etc.

[0055] First, compare the main survey lines to determine the formation trend of the main tectonic direction in the work area. This is mainly done by comparing the formation strikes of the main survey line and the formations on both sides of it. If the survey line density is large, control survey lines can be selected. The criterion is that the formation strike of the survey lines inside two control survey lines is basically the same as that of the control survey lines, that is, the control survey lines can determine the formation strikes of the internal survey lines. Generally, the formation structure of the main survey line is easier to determine.

[0056] Then, determine the formation strike of the connecting survey lines. The method is the same as that of the main survey lines. The formation strike of the connecting survey lines is generally more complex, and the difficulty of seismic interpretation is often greater than that of the main survey lines. Also, the number of connecting survey lines is often less. Therefore, generally, control survey lines are not set for connecting survey lines under normal circumstances. However, if necessary, control survey lines for connecting survey lines can also be set, and the method is the same as the method for setting control survey lines for main survey lines.

[0057] It should be emphasized that seismic pre-interpretation work is very necessary and important. By continuously comparing survey lines and initially establishing a spatial formation structure model (spatial trend model of formations), it is beneficial to guide the next formal interpretation work. The selection of control survey lines can reduce a large amount of unnecessary interpretation work before the establishment of the interpretation framework and improve the interpretation efficiency, especially when the interpretation plan is adjusted. The probability of incorrect interpretation plans in difficult interpretation areas is higher. Identifying the difficult areas in the work area in advance helps with the next interpretation work.

[0058] After seismic pre-interpretation, seismic pre-interpretation results diagrams need to be formed. For example, Figure 2 as shown, it mainly includes determining non-control lines (lines other than control lines are non-control lines), which are not interpreted temporarily during formal interpretation and will be interpreted after the late-stage stratigraphic framework plan is determined, which will improve the interpretation efficiency; in addition, by establishing a spatial trend model of the strata, uncertain interpretation areas such as shallow gas and complex structural imaging areas are clarified and marked on the diagram, and based on this, high-risk lines are divided, and such areas will be avoided first during formal interpretation.

[0059] Seismic pre-interpretation work is very important in the whole process. Traditional seismic interpretation generally directly interprets without the step of pre-interpretation at all. But in fact, pre-interpretation is quite important. Through pre-interpretation, a series of risk points during later formal interpretation can be avoided, and the chance of making mistakes can be reduced. Therefore, in fact, the later interpretation speed will be more organized and targeted, and the interpretation efficiency is actually higher. Generally speaking, seismic pre-interpretation takes at least more than 1 day, and large-scale interpretation projects even require more than 3 days.

[0060] Step 2: Determination of zonal interpretation

[0061] During the actual operation of zonal interpretation, high-risk polygons are divided on the interpretation results diagram according to the seismic pre-interpretation diagram, and the areas within the high-risk polygons do not participate in the preliminary interpretation work for the time being, as follows:

[0062] First, further clarify the distribution range of difficult areas (high-risk areas) according to the pre-interpretation results diagram. If the distribution range is small and cannot form a grid, it can directly participate in the interpretation work without zoning, and only need to pay attention to the relevant areas during interpretation;

[0063] If the distribution range is concentrated in a certain area and forms a grid-like distribution, then this area needs to be excluded during interpretation, that is, it does not participate in the construction of the preliminary interpretation framework first, and waits until the interpretation of other areas is completed before concentrating on tackling this complex area.

[0064] The basic guiding principle of zonal interpretation is to start with the easy and then deal with the difficult, and interpret the areas with high certainty first and then the areas with low certainty. The advantage of this is that it can simplify the complex, improve the success rate of interpretation, and further reduce the modification of the plan during later interpretation. Even if the plan is modified, it is mainly concentrated in complex areas and has little impact on other areas. In this way, the modification range can be further reduced, and the situation where the modification of a small part of the area affects the whole area will not occur.

[0065] Step 3: Conduct preliminary interpretation using the stratigraphic trend method

[0066] When making a preliminary interpretation, the main core idea regarding the specific interpretation work is not to get bogged down in specific details. Instead, a trend interpretation is made for the horizons of the interpretation (the so-called trend interpretation only requires a general interpretation according to the approximate trend of the formation strike. For example, if the strike of a certain formation first goes up, then down, and then up again, a general interpretation can be made according to the up-down-up trend). Only a detailed interpretation is carried out near the intersection points of the survey lines (the detailed interpretation can be understood as an accurate interpretation, and more precision is required during the interpretation), and the closing points of the survey lines are used as the final quality evaluation criteria. The specific approach is as follows:

[0067] First, make a trend interpretation for the main survey lines. When it is difficult to determine formation tracing in cases such as encountering faults and shallow gas fuzzy zones, since it is very difficult to judge the formation strike at this time and there must be multiple solutions in the interpretation scheme, there is no need to get too entangled here. Just interpret according to the formation trend. For the areas near the intersection points of the survey lines, the interpretation needs to be refined, that is, it is necessary to interpret along the isophase axis, and only the general formation strike needs to be marked for the rest. Complete the interpretation of the other main survey lines according to the same scheme.

[0068] After the interpretation of the main survey lines is completed, the connecting survey lines will show the interpretation points of the main survey lines. If the interpretation scheme is correct, only the individual interpretation points need to be connected. However, practice has proved that this situation is relatively rare. Generally, after connecting the individual interpretation points, the following situations will occur:

[0069] 1) The interpretation points switch back and forth between multiple sets of formations. At this time, there is no need for an accurate interpretation. Just find the middle formation according to the principle of linear regression for a trend formation interpretation;

[0070] 2) There is an obvious deviation between a certain interpretation point and other interpretation points. Excluding the possibility of a drastic change in the formation structure, generally there is a problem in the interpretation at this time. Since the number of such interpretation points is usually small, interpolation interpretation generally needs to be carried out relying on other points, and then return to the main survey line to correct the corresponding interpretation points;

[0071] 3) The interpretation points are concentrated between two sets of horizons. For example, the first half is in the upper horizon and the second half is in the lower horizon. At this time, it is necessary to first determine whether there is a fault near the conversion point:

[0072] If there is a fault and the formation strike conforms to the objective law, it indicates that the interpretation is correct. Only mark the fault and the fault strike on the interpretation plan;

[0073] If there is no fault and there is no drilling control or other index control, it should be handled according to the principle of simplicity, that is, adopt the simpler interpretation scheme and explain the selected formation strike in the interpretation scheme; in addition, if the distance between the two sets of formations is relatively far, an additional set of interpretation horizons can also be considered.

[0074] Complete the preliminary interpretation after the interpretation of the connecting survey lines is completed.

[0075] Step 4: Generate the preliminary depth map

[0076] After the preliminary interpretations of the main survey lines and the connecting survey lines are completed, although the intersections are not completely closed, a preliminary depth map of the strata can still be generated. On the depth map, mainly determine whether the interpreted strata trend is consistent with the expectation, that is, there will be no principled error problems.

[0077] Secondly, for the areas where the depth isolines of the strata cross and the intersections are not closed during interpretation, etc., make markings. Generally, it is not necessary to divide high-risk polygons at this time, and only simple markings are required.

[0078] In the areas where the isolines are dense on the depth map, it is generally related to faults. It is necessary to comprehensively judge in combination with the seismic profiles, and preliminarily mark the extension of the faults on the depth map, providing an important reference for the next intersection closure interpretation.

[0079] Step 5: Intersection closure interpretation

[0080] Intersection closure is the fundamental principle of interpretation and also the ultimate quantitative index of seismic interpretation. The intersection closure interpretation generally uses comprehensive factors such as faults, strata trends, and structures to continuously infer and modify repeatedly, and continuously adjust the horizons to conform to the laws of geological structures. This is basically the same as the traditional interpretation method and will not be elaborated here.

[0081] Step 6: Interpretation of the areas within the high-risk polygons

[0082] After the interpretation of the low-risk areas is completed, then interpret the high-risk areas. The interpretation method for the high-risk areas is basically the same as that for the low-risk areas, but it is relatively more complex and more difficult, and basically repeats steps 3 - 5.

[0083] Step 7: Precise tracing of the interpreted strata

[0084] After the interpretation of the horizons is completed, that is, all the intersections of the survey lines are closed and the interpretation results conform to the geological laws, then conduct precise tracing of the interpreted horizons. The advantage of doing this is to speed up the interpretation speed and avoid the repeated workload caused by repeatedly modifying the interpretation plan. In fact, it is to refine the previous interpretation, which is a relatively mature and commonly used technical means.

[0085] Step 8: Interpretation of other horizons

[0086] According to the operation methods in steps 1 - 7, complete the work of key horizon interpretation, basement interpretation, and other minor horizon interpretations in sequence (generally, a certain work area includes key horizons, basement, and other minor horizons, which are professional terms). Generally, key horizon and basement interpretations need to be completed first, which can be used as constraint horizons for other horizon interpretations and reduce the difficulty of other horizon interpretations.

[0087] To further understand the solution of the present invention, the method of the present invention will be illustrated below by taking the interpretation project of the cross - sea channel in Sea A as an example:

[0088] The cross - sea channel project in Sea A is mainly for the preliminary feasibility analysis of building an undersea tunnel across the Strait of Sea A, and seismic exploration is the most important work in the early stage. This project was approved in 1992, and during nearly 30 years of preliminary research, more than 10,000 kilometers of high - resolution seismic data have been accumulated. Figure 3 These are several typical seismic profiles. It can be seen that the seismic profiles collected by different devices vary greatly, and their differences are mainly related to the devices used. However, even for the seismic profiles collected by the air - gun single - channel method in 2016 and 2017, their signal - to - noise ratios are relatively low, and it is simply impossible to start with the traditional interpretation method of first faults and then strata. At the same time, these seismic data have approximately 4 million points. If the traditional interpretation method is used, even just tracking the seabed (the event is clear and there is no ambiguity) will take about 1 week, and the entire project will take more than 5 months, with a total of 5 sets of horizons to be interpreted. On average, it takes nearly 1 month to interpret a single set of horizons. Therefore, the time cost is huge.

[0089] In addition, due to the large scope of the work area, it is very difficult to interpret a large number of cross - lines. The main difficulty is that it is more difficult to close the intersections. If the interpretation scheme is unreasonable and needs to be revised, then all the associated cross - lines need to be reinterpreted, which is extremely likely to cause the collapse of the interpretation project. This is because the scope involved after modification is too large, which is likely to cause chaos in the overall interpretation scheme, and even it is easy to forget which places need to be modified. The present invention is precisely formed by continuously researching new technical methods and continuously correcting during the interpretation in view of the many difficulties existing in this project.

[0090] After analyzing the seismic profiles in the work area, the work area as a whole shows obvious three - part tectonic units. Figure 4 This is a typical main survey line in the work area (the thick black line in the figure). From its basement characteristics, it can be seen that the entire work area is divided into the large - scale subsidence area of the A Bay Basin, the uplift area of Island B, and the secondary subsidence area of the C Sea Basin. Through the connecting survey lines, it can be obtained that the survey lines perpendicular to the tectonic direction as a whole show a sedimentary characteristic of being thicker in the south and thinner in the north. Generally, the basement of the survey lines is relatively clear, but in the area of the A Bay Basin within the box, due to the large burial depth of the basement, the interpretation uncertainty is high, which is mainly located in the northwest of the work area, as Figure 4shown by the thin black line. Since the area where it is located shows a grid distribution, the area where it is located is defined as a high-risk area. For example, Figure 5 shown, during the later interpretation, this part of the area will not be interpreted temporarily.

[0091] Figure 5 It also involves the division of non-control survey lines. The main problems of the seismic profiles at the positions of the thicker survey lines are too low signal-to-noise ratio and unclear basement. Therefore, they are divided into non-control survey lines. The division of other non-control survey lines is mainly because there are seismic profiles with basically the same seismic appearance near them. Therefore, these non-control survey lines can be not interpreted first during the interpretation.

[0092] The preliminary interpretation results using the stratigraphic trend method are as shown in Figure 6 shown. It can be seen that during the interpretation, only the general trend of the strata is traced roughly, not paying attention to details. Therefore, the actual interpretation speed is very fast. For the closed points with small deviations, if they do not cause ambiguity in the stratum interpretation, there is no need to pay excessive attention. For the closed points with large deviations (such as those shown in the circles in Figure 6 ), it is necessary to find the corresponding survey lines again for interpretation.

[0093] Figure 7 is the preliminary generated depth map. As can be seen from Figure 7 shown, its overall trend is basically the same as that in the pre-interpretation, indicating that there are no major problems in the overall interpretation. The area with dense contour lines in the upper right part of the map sheet is related to the fault and is confirmed by the surrounding survey lines. The contour lines in some areas change chaotically, which is related to the possible problems still existing in the preliminary interpretation and is also the key area for the intersection closure interpretation. The depth map can further guide the interpretation work and make the interpretation work more targeted.

[0094] The intersection closure interpretation is actually a kind of step-by-step convergence and refinement work for the trend interpretation. Since the stratigraphic trend is basically correct, it ensures that there will be no principled error problems in the overall interpretation and will not lead to serious consequences of a large number of overthrows and reconstructions, which greatly improves the interpretation speed. Subsequently, the interpretation work in the high-risk area is carried out. The method is the same as the above method. However, due to the too low signal-to-noise ratio in this area, most of them can only ensure the correctness of the stratigraphic trend. Its interpretation reliability and accuracy are still lacking compared with other areas. After all areas are interpreted and the interpretation results are more in line with the objective reality and meet the overall interpretation requirements, finally, the precise tracing of the strata is carried out. After using this method, the interpretation speed is greatly improved. The original one-month work is compressed to be completed within one week and good results are obtained in practice.

[0095] Figure 8This is the result of the formation trend method interpretation in this work area. After interpreting the basement, the trends of other formations are generally consistent with that of the basement formation. Thus, the basement formation can serve as a good constraint condition for the interpretation of other formations. The interpretation method for other formations is the same as the aforementioned method. From the results, this interpretation is relatively reasonable and basically meets the requirements and purposes of the interpretation. This method has been well verified in the cross-sea channel interpretation project, and at the same time, it greatly reduces the interpretation time, reflecting the effectiveness of this method.

[0096] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention in other forms. Any person skilled in the art may use the technical content disclosed above to make changes or modifications into equivalent embodiments with equivalent changes and apply them to other fields. However, as long as it does not depart from the technical solution content of the present invention, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A fast seismic interpretation method based on formation trend, characterized in that, it includes the following steps: Step A, seismic pre-interpretation: including determination of formation trends of main survey lines and connecting survey lines, selection of control survey lines, and division of high-risk survey lines, generating a seismic pre-interpretation result map; Step B, determination of zonal interpretation, further clarifying the distribution range of high-risk survey lines according to the seismic pre-interpretation result map to determine high-risk areas, and interpreting horizons based on formation trends: Step B1, first interpret the low-risk areas outside the high-risk areas; Step B11, perform preliminary interpretation using the formation trend method: make a trend interpretation of the interpreted horizons, only make precise interpretations near the intersections of survey lines, and use the closure of survey lines as the final quality evaluation criterion to complete the interpretation of main survey lines and connecting survey lines; Step B12, generate a preliminary depth map: generate a preliminary depth map after the interpretation of main survey lines and connecting survey lines, and mark the non-closed intersections and fault areas; Step B13, intersection closure interpretation: continuously adjust the horizons based on the intersection closure principle to conform to the geological structure law; Step B2, interpret the high-risk areas: repeat Steps B11 - B13 according to the idea of Step B1 to complete the interpretation of high-risk areas; Step C, precise tracing of interpreted formations: after completing the horizon interpretation, perform precise tracing of the interpreted horizons; Step D, complete the interpretation of key horizons, basement interpretation, and interpretation of other secondary horizons according to the interpretation ideas of Steps A - C.

2. The fast seismic interpretation method based on formation trend according to claim 1, characterized in that: The specific implementation of Step A is as follows: Step A1, first compare the main survey lines to determine the trend of the formation in the main tectonic direction in the work area: by comparing the formation strikes of the main survey lines and the formations on both sides of them, select control survey lines, and determine the formation strike through the control survey lines; Step A2, then determine the formation strike of the connecting survey lines according to the same idea as Step A1; Step A3, divide high-risk survey lines based on shallow gas and imaging fuzzy areas.

3. The fast seismic interpretation method based on formation trend according to claim 1, characterized in that: In Step B, when performing zonal interpretation: If the distribution range of high-risk survey lines is small, no division of high-risk areas and low-risk areas is carried out, and directly interpret the formation, and pay attention to the following high-risk survey lines; If the distribution range of high-risk survey lines is concentrated in a certain area and is distributed in a grid pattern, then divide high-risk areas and low-risk areas.

4. The fast seismic interpretation method based on formation trend according to claim 1, characterized in that: In Step B11, when performing preliminary interpretation, it is specifically as follows: Step (1): First make a trend interpretation of the main survey lines: interpret according to the formation trend, mark the formation strike, and for the areas near the intersections of survey lines, interpret along the same-phase axis to achieve precise interpretation near the intersections of survey lines, and complete the interpretation of the remaining main survey lines according to the same plan; Step (2): After the interpretation of the main survey lines is completed, the connecting survey lines show the interpretation points of the main survey lines. If the interpretation plan is correct, then connect each interpretation point to complete the interpretation of the connecting survey lines.

5. The rapid seismic interpretation method based on formation trend according to claim 4, characterized in that: In step B11, after connecting each interpretation point in step (2), the following situations may occur: 1) The interpretation points switch back and forth between multiple sets of formations. In this case, only the middle formation needs to be found according to the principle of linear regression for trend formation interpretation; 2) There is a deviation between an interpretation point and other interpretation points. In this case, interpolation interpretation is performed relying on other points, and then the corresponding interpretation points are corrected on the main survey line; 3) The interpretation points are concentrated between two sets of horizons. In this case, it is necessary to first determine whether there is a fault near the conversion point: If there is a fault and the formation strike conforms to the objective law, it indicates that the interpretation is correct, and the fault and its strike are marked on the seismic pre-interpretation result map; If there is no fault and there is no drilling control or other index control, it should be processed according to the principle of simplification, and the selected formation strike should be described.

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