A structural interpretation correction method for model forward and stack profile interactive analysis

Abstract

This invention discloses a structural interpretation correction method based on model forward modeling and interleaved profile analysis, which proceeds in the following steps: S1. For structurally complex areas where seismic profile interpretation has multiple solutions, perform multi-scheme interpretation to obtain various structural interpretation schemes; S2. For each structural interpretation scheme, design a corresponding geological model to obtain multiple geological models; S3. Perform model forward modeling on each of the multiple geological models to obtain multiple forward modeling horizontally stacked profiles; S4. Interleave the multiple forward modeling horizontally stacked profiles with the processed horizontally stacked profiles for analysis; S5. Determine the optimal structural interpretation scheme. This invention belongs to the field of seismic exploration technology for oil and gas. It can correct and verify structural interpretation schemes during the structural interpretation process, making the interpreted structural results closer to the actual subsurface structural morphology, fundamentally improving the accuracy of structural results, and achieving the goal of accurately predicting subsurface structural morphology.

Description

Technical Field

[0001] This invention belongs to the field of seismic exploration technology for oil and gas, and relates to an interpretation method for improving the accuracy of structural results. Specifically, it is a structural interpretation and correction method based on model forward modeling and overlapping profile interactive analysis. Background Technology

[0002] For steep, mountainous structures with complex surface and subsurface features, the structural morphology on seismic depth profiles is often influenced by various factors and cannot fully reflect the attitude of strata, fault locations, etc., resulting in significant differences between the seismic profile and the actual underground structural morphology. This is especially true when strata are steeply dipping, have complex velocity structures, and low signal-to-noise ratios; seismic migration profiles often contain numerous artifacts. Following the conventional principle of interpreting seismic profiles in the same direction, these profiles often differ significantly from the structural morphology of later actual drilling geological profiles, thus greatly impacting the size of structural traps, drilling deployment, and oil and gas reserve assessment.

[0003] Currently, in production practice, interpreters often use time migration or depth migration profiles for stratigraphic correlation interpretation. In structurally complex areas, they reconstruct formation thickness and dip using surface structures and drilled well data, then combine this with seismic interpretation methods to interpret the structural results of the inland area. However, due to the lack of analysis and correction processes, these results often introduce significant errors in structurally complex regions, distorting all extensions built upon them and leading to incorrect well placement. How to utilize effective methods to ensure accurate and reliable formation dip and fault locations, enabling correct judgments in actual structural interpretation work and obtaining accurate and reliable structural interpretation results, thus providing reliable trap information for well placement and reservoir evaluation, is a crucial challenge that interpreters need to solve. Summary of the Invention

[0004] The purpose of this invention is to provide a structural interpretation correction method for model forward modeling and superimposed profile interactive analysis. This method can back-test and modify the processed offset profiles and structural interpretation schemes, make reasonable judgments on the steepness of strata dip and fault location on some complex structural seismic profiles, ensure their rationality, and make the structural interpretation schemes of seismic profiles closer to the actual structural morphology. This plays a positive role in realizing the structural morphology and traps in complex structural areas.

[0005] To achieve the above objectives, the technical solution adopted by this invention is as follows:

[0006] A method for constructing interpretation and correction of model forward modeling and superimposed profile interactive analysis, which proceeds in the following steps:

[0007] S1. For structurally complex areas, multiple interpretation schemes are carried out for structural parts where there are multiple solutions for seismic profile interpretation, resulting in various structural interpretation schemes.

[0008] S2. For each structural interpretation scheme, design a corresponding geological model to obtain multiple geological models;

[0009] S3. Perform forward modeling on various geological models to obtain multiple forward modeling horizontally superimposed profiles.

[0010] S4. Perform interactive analysis on multiple forward-modeled horizontal stacked profiles and the processed horizontal stacked profiles, and select a set of the closest forward-modeled horizontal stacked profiles and processed horizontal stacked profiles.

[0011] If the parameters of the selected closest forward-modeled horizontal stacked profile and the processed horizontal stacked profile meet the requirements, then the interpretation scheme corresponding to the forward-modeled horizontal stacked profile is the best construction interpretation scheme; otherwise, proceed to step S5.

[0012] S5. Based on the selected closest forward-modeled horizontal stacked profile, adjust the parameters of the selected processed horizontal stacked profile, and use the adjusted processed horizontal stacked profile to deduce the corresponding geological model. Then, further perform forward modeling to obtain the corresponding forward-modeled horizontal stacked profile. Stop parameter adjustment when the parameters of the obtained forward-modeled horizontal stacked profile meet the requirements of the closest forward-modeled horizontal stacked profile selected in step S4. Use the geological model corresponding to the last obtained forward-modeled horizontal stacked profile to deduce the corresponding structural interpretation scheme, which is the optimal structural interpretation scheme.

[0013] As a limitation, in step S3, when performing forward modeling, the structural interpretation results of the stratigraphy and faults are used to perform model-based forward modeling.

[0014] As a second limitation, when performing interactive analysis between multiple forward-modeled horizontally stacked profiles and the processed horizontally stacked profiles, the two are compared to see whether they are consistent in terms of structural morphology, attitude, and stratigraphic thickness variations.

[0015] As a third limitation, in step S5, when the geological model corresponding to the last obtained forward-modeled horizontally stacked profile is used to deduce the corresponding structural interpretation scheme, the forward-modeled time migration profile and depth migration profile in the last obtained forward-modeled horizontally stacked profile are used to correct the structural interpretation scheme in step S1, and the dip angle of the strata and the location of the faults in the structural interpretation scheme are corrected and adjusted, so as to finally obtain the optimal structural interpretation scheme.

[0016] The present invention, by adopting the above-described technical solution, achieves the following technical advancements compared to existing technologies:

[0017] (1) This invention provides a technical method for back-testing the processed offset profile and structural interpretation scheme, and for modifying and correcting the interpretation results during the interpretation process. This method integrates geological, seismic, structural modeling and model forward modeling comprehensive interpretation technology, which can make reasonable judgments on the steep dip of strata and the location of fault points on some complex structural seismic profiles, so that the structural interpretation results of the seismic profile are closer to the actual structural morphology, and play a positive role in realizing the structural morphology and traps of complex structural areas.

[0018] (2) For areas with drilled wells, the results of structural interpretation can be corrected by restoring the wells. However, for areas without drilled wells, where the underground structure is complex, the signal-to-noise ratio of seismic data is low, and there may be multiple interpretation schemes for structural interpretation, traditional methods cannot correct structural results. Therefore, this invention will conduct a detailed analysis of structural parts with multiple interpretation schemes and provide multiple possible structural interpretation schemes to ensure the accuracy of the results.

[0019] This invention belongs to the field of seismic exploration technology for oil and gas. It can correct and verify the structural interpretation scheme during the structural interpretation process, making the interpreted structural results closer to the actual underground structural morphology, thereby fundamentally improving the accuracy of structural results and achieving the goal of accurately predicting the underground structural morphology. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0021] In the attached diagram:

[0022] Figure 1 This is a flowchart of an embodiment of the present invention;

[0023] Figure 2 This is a depth cross-sectional view of an embodiment of the present invention;

[0024] Figure 3 a is the seismic depth profile corresponding to the construction interpretation scheme 1 in the embodiment of the present invention;

[0025] Figure 3 b is an embodiment of the present invention. Figure 3 a corresponds to the geological model diagram;

[0026] Figure 3 c is the forward modeling horizontal overlay cross-section corresponding to the construction explanation scheme 1 of the present invention;

[0027] Figure 3 d is the seismic depth profile corresponding to the construction interpretation scheme 2 in this embodiment of the invention;

[0028] Figure 3 e is an embodiment of the present invention. Figure 3 The geological model corresponding to d;

[0029] Figure 3 f is the forward modeling horizontal overlay cross-section corresponding to the construction explanation scheme 2 of the present invention;

[0030] Figure 4 a is a horizontal overlay cross-sectional view of the processing in an embodiment of the present invention;

[0031] Figure 4 b is a forward-modeling horizontally superimposed cross-sectional view corresponding to the construction explanation scheme 1 of the present invention;

[0032] Figure 4 c is the forward-modeling horizontal overlay cross-section corresponding to the construction explanation scheme 2 of the present invention;

[0033] Figure 5 a is a forward-modeling horizontally superimposed cross-sectional view corresponding to the construction explanation scheme 1 of the present invention;

[0034] Figure 5 b is a horizontal overlay cross-sectional view of the processing in an embodiment of the present invention;

[0035] Figure 5 c is the seismic depth profile corresponding to the construction explanation scheme 1 of the present invention. Detailed Implementation

[0036] The preferred embodiments of the present invention will now be described with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0037] Example: A construction interpretation and correction method for interactive analysis of model forward modeling and superimposed profiles.

[0038] like Figure 1 As shown, this embodiment is performed in the following order:

[0039] S1. Perform structural interpretation on the processed depth migration profile, adopt the principle of phase tracking as much as possible, eliminate obvious distortions and artifacts on the seismic profile, and make a structural interpretation scheme that conforms to the seismic geological law.

[0040] For structurally complex regions, multiple interpretation schemes are applied to structural parts where seismic profile interpretation has multiple solutions, resulting in various structural interpretation schemes; for example... Figure 2In structural interpretation scheme 1, based on the fault segmentation of the same-direction axis, the fault can be interpreted as being located near the bottom of the syncline. However, based on the stratigraphic geological conditions and the relationship between wave groups and wave systems, the fault can also be interpreted as being located on the slope of the structure. Therefore, the structural interpretation scheme has multiple solutions in this case. Thus, in areas where structural interpretation is uncertain, we present multiple interpretation schemes for verification. In this embodiment, two cases are presented: structural interpretation scheme 1 and structural interpretation scheme 2, such as... Figure 3 Figure a shows the depth profile of the seismic profile corresponding to structural interpretation scheme 1. Figure 3 d is the depth profile of the seismic profile corresponding to interpretation scheme 2;

[0041] S2. For each structural interpretation scheme, a corresponding geological model is designed, resulting in multiple geological models. This embodiment presents two possibilities. Figure 3 b is Figure 3 a corresponds to the geological model diagram; Figure 3 e is Figure 3 The geological model diagram corresponding to d;

[0042] S3. Perform forward modeling on various geological models to obtain the corresponding forward-modeled horizontally stacked profiles, such as... Figure 3 Figure c shows the forward-modeled horizontal stacking profile corresponding to interpretation scheme 1. Figure 3 f shows the forward modeling horizontal stacking profile corresponding to interpretation scheme 2;

[0043] When conducting model forward modeling, the structural interpretation results of stratigraphy and faults are used to carry out model-based forward modeling;

[0044] S4, such as Figure 4 As shown in a, 4b, and 4c, multiple forward-modeled horizontal stacked profiles are interactively analyzed with the treated horizontal stacked profiles to compare whether they are consistent in terms of structural morphology, attitude, and stratigraphic thickness variations. A set of forward-modeled horizontal stacked profiles that is closest to the treated horizontal stacked profiles is selected. The interpretation scheme corresponding to this set of forward-modeled horizontal stacked profiles is the most reasonable interpretation scheme. In this case, the forward-modeled horizontal stacked profile corresponding to structural interpretation scheme 1 is consistent with the treated horizontal stacked profile. Therefore, structural interpretation scheme 1 is determined as the final interpretation scheme.

[0045] If the parameters of the selected closest forward-modeled horizontal stacked profile and the processed horizontal stacked profile meet the requirements, then construction interpretation scheme 1 is the best construction interpretation scheme; otherwise, proceed to step S5.

[0046] S5. Based on the selected closest forward-modeled horizontal stacked profile, adjust the parameters of the selected processed horizontal stacked profile, and use the adjusted processed horizontal stacked profile to deduce the corresponding geological model. Then, further perform forward modeling to obtain the corresponding forward-modeled horizontal stacked profile. Stop parameter adjustment when the parameters of the obtained forward-modeled horizontal stacked profile meet the requirements of the closest forward-modeled horizontal stacked profile selected in step S4. Use the geological model corresponding to the last obtained forward-modeled horizontal stacked profile to deduce the corresponding structural interpretation scheme, which is the best structural interpretation scheme.

[0047] like Figure 5 As shown in a, 5b, and 5c, when the geological model corresponding to the last obtained forward-modeled horizontally stacked profile is used to deduce the corresponding structural interpretation scheme, the forward-modeled time migration profile and depth migration profile in the last obtained forward-modeled horizontally stacked profile are used to correct the structural interpretation scheme of the corresponding step S1. The dip angle of the strata and the location of the faults in the structural interpretation scheme are corrected and adjusted, and finally the optimal structural interpretation scheme is obtained.

[0048] In this embodiment, the depth offset profile corresponds to... Figures 2-5 "Depth profile" in the geological model; corresponding to the geological model Figures 2-5 The "forward model" in the text; corresponding to the forward model horizontal superimposed profile. Figures 2-5 The "forward profile" in the text.

Claims

1. A method for constructing, interpreting, and correcting models through forward modeling and overlapping profile interaction analysis, characterized in that, Follow these steps in sequence: S1. For structurally complex areas, multiple interpretation schemes are carried out for structural parts where there are multiple solutions for seismic profile interpretation, resulting in various structural interpretation schemes. S2. For each structural interpretation scheme, design a corresponding geological model to obtain multiple geological models; S3. Perform forward modeling on various geological models to obtain multiple forward modeling horizontally superimposed profiles. S4. Perform interactive analysis between the multiple forward-modeled horizontal stacked profiles and the processed horizontal stacked profiles from the actual collected data, select the forward-modeled horizontal stacked profile that is closest to the processed horizontal stacked profile, and record its corresponding initial construction interpretation scheme. If the parameters of the selected closest forward-modeled horizontal stacked profile are close to those of the processed horizontal stacked profile in accordance with the preset requirements, then the initial construction interpretation scheme corresponding to the forward-modeled horizontal stacked profile is the final optimal construction interpretation scheme. If the preset requirements are not met, proceed to step S5; S5. Using the closest forward-modeled horizontal stacked profile selected in step S4 as a reference, adjust the internal processing parameters of the processed horizontal stacked profile to obtain a parameter-adjusted horizontal stacked profile; then use the parameter-adjusted horizontal stacked profile to inversely calculate a new geological model; perform forward modeling on the new geological model again to obtain a new forward-modeled horizontal stacked profile. The new forward modeling horizontal stacked profile is compared with the closest forward modeling horizontal stacked profile selected in step S4. If the similarity of the parameters of the two meets the preset requirements, the iteration is stopped, and the tectonic interpretation scheme derived from the geological model corresponding to the new forward modeling horizontal stacked profile is taken as the final best tectonic interpretation scheme. If it does not meet the requirements, repeat the adjustment, reverse calculation, and forward calculation process in this step until it meets the requirements.

2. The construction interpretation and correction method for model forward modeling and superimposed profile interactive analysis according to claim 1, characterized in that, In step S3, when performing forward modeling, the structural interpretation results of the stratigraphy and faults are used to carry out model-based forward modeling.

3. The construction interpretation and correction method for model forward modeling and superimposed profile interactive analysis according to claim 1 or 2, characterized in that, When performing interactive analysis between multiple forward-modeled horizontally stacked profiles and the processed horizontally stacked profiles, the consistency between the two profiles in terms of structural morphology, attitude, and stratigraphic thickness is compared.

4. A method for constructing, interpreting, and correcting model forward modeling and superimposed profile interactive analysis according to claim 1 or 2, characterized in that, In step S5, when the geological model corresponding to the last obtained forward-modeled horizontal stacked profile is used to deduce the corresponding structural interpretation scheme, the forward-modeled time migration profile and depth migration profile in the last obtained forward-modeled horizontal stacked profile are used to correct the structural interpretation scheme in step S1. The dip angle of the strata and the location of the faults in the structural interpretation scheme are corrected and adjusted, and finally the optimal structural interpretation scheme is obtained.

5. The method for constructing, interpreting, and correcting model forward modeling and superimposed profile interactive analysis according to claim 3, characterized in that, In step S5, when the geological model corresponding to the last obtained forward-modeled horizontal stacked profile is used to deduce the corresponding structural interpretation scheme, the forward-modeled time migration profile and depth migration profile in the last obtained forward-modeled horizontal stacked profile are used to correct the structural interpretation scheme in step S1. The dip angle of the strata and the location of the faults in the structural interpretation scheme are corrected and adjusted, and finally the optimal structural interpretation scheme is obtained.

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