An oil layer logging identification method and system based on paleogeomorphology analysis constraint

Abstract

The application provides a kind of oil layer well logging identification method and system based on palaeogeomorphology analysis constraint, method includes: according to the geological sedimentary environment information of the target area obtained, reconstructs the palaeogeomorphology feature map of target area, draws out the palaeogeomorphology unit distribution map in target area, according to the palaeogeomorphology unit distribution map in target area, determine the palaeogeomorphology unit type where drilling is located;According to well logging data, oil-water layer is preliminarily identified, and oil layer and water layer are divided, to obtain oil layer preliminary identification result;According to the palaeogeomorphology unit type where well logging is located, obtain the geomorphological features of palaeogeomorphology unit, optimize oil layer preliminary identification result, to obtain oil layer optimization identification result.The application can more accurately identify the oil layer affected by palaeogeomorphology by introducing palaeogeomorphology analysis constraint when identifying oil layer, reduce misidentification and missed identification, improve the reliability and stability of oil layer identification.

Description

Technical Field

[0001] The present invention relates to the field of geological exploration, and more particularly to a method and system for identifying oil layer logging based on paleo-geomorphological analysis constraints. Background Art

[0002] Oil and natural gas are among the world's most important energy sources. The development of oil exploration and production technologies plays a vital role in ensuring energy supply and promoting economic development. Reservoir exploration is a key component of the oil industry, and accurate identification of oil reservoirs is crucial. Over the past few decades, advancements in exploration technology have made reservoir logging a crucial tool in oil exploration, particularly in complex geological environments. Reservoir logging interpretation provides essential data for the development of oil and gas resources.

[0003] However, traditional reservoir logging techniques have limitations in complex geological settings, particularly in areas where paleogeomorphology controls reservoir formation and distribution. Traditional reservoir identification methods rely heavily on well logging data (such as resistivity and gamma-rays), which often overlook the impact of paleogeomorphic features on reservoir distribution. In many cases, paleogeomorphic features play a crucial role in determining reservoir distribution, reservoir properties, and reservoir formation conditions. This information is particularly evident in reservoirs with significant paleogeomorphic influences, where traditional logging techniques often fail to effectively capture this information.

[0004] Paleomorphology plays a crucial role in the development of oil reservoirs. The distribution of paleomorphic units influences reservoir properties such as sediment type, thickness, lithology, and porosity, directly impacting the accumulation and distribution of oil and gas. Under certain unique paleomorphic conditions (such as incised valleys and alluvial fans), the structure and distribution of oil reservoirs are highly heterogeneous and complex due to the unique sedimentary environment and reservoir-forming conditions.

[0005] Especially in areas controlled by incised river valleys or other paleo-geomorphological features, the distribution of oil reservoirs is not only influenced by lithologic characteristics but also strongly controlled by paleo-geomorphological units (such as river valleys and highlands). Therefore, relying solely on well logging curves and traditional lithologic identification methods makes it difficult to accurately determine the location and distribution of oil reservoirs, nor to reveal the impact of paleo-geomorphology on oil reservoir development.

[0006] In complex geological environments, the main technical challenges faced in oil reservoir identification include:

[0007] (1) Low accuracy in oil layer identification: Traditional well logging methods rely mainly on the interpretation of logging curves, and the morphological changes of these curves may be affected by a variety of geological factors, such as sedimentary environment, lithology, porosity, etc. In areas controlled by paleo-geomorphology, logging data often cannot fully reflect the true distribution of oil layers.

[0008] (2) It is difficult to comprehensively consider complex geological factors: Traditional oil layer logging identification methods often ignore the complex geological background and historical evolution of the region, especially in areas controlled by paleo-geomorphology. Traditional methods find it difficult to effectively combine paleo-geomorphological characteristics with oil reservoir formation conditions, resulting in misjudgment or omission.

[0009] (3) Insufficient correlation between paleogeomorphology and reservoir properties: Paleogeomorphological features (such as river channel deposits, alluvial fans, etc.) have an important impact on the reservoir formation conditions of oil layers, but traditional oil layer logging technology fails to fully utilize this information, resulting in the inability to accurately assess the reservoir properties and development potential of oil layers.

[0010] Conventional logging technology, with its rich data resources and high cost-effectiveness, plays a crucial role in the interpretation and identification of oil and water layers. Currently, logging technologies broadly fall into three categories: digital logging (such as borehole-compensated acoustic, neutron, and formation density logging), digitally controlled logging (spontaneous potential, natural gamma, caliper, vertical seismic profiling, and natural gamma ray spectroscopy logging), and imaging logging (nuclear magnetic resonance, borehole micro-electrical scanning and acoustic imaging, array induction, and azimuthal laterometry). The identification of oil and water layers typically utilizes a combination of qualitative and quantitative methods. Qualitative analysis focuses on longitudinal comparison and overlay plots of single-well logging curves, as well as comprehensive comparison and crossplots of multi-well logging curves. Quantitative analysis, on the other hand, relies on rock electrical experiments, using Archie's formula or logging signals such as nuclear magnetic resonance to accurately determine oil (or water) saturation. Summary of the Invention

[0011] In oil reservoir development areas controlled by paleo-geomorphology, traditional logging identification methods do not take paleo-geomorphological factors into consideration, resulting in reduced accuracy and prone to misidentification or missed identification. Based on this, the present invention provides an oil layer logging identification method and system based on paleo-geomorphological analysis constraints.

[0012] According to a first aspect of the present invention, a method for oil layer logging identification based on paleo-geomorphological analysis constraints is provided, comprising:

[0013] Reconstructing a paleo-geomorphic feature map of the target area based on the collected geological sedimentary environment information of the target area, drawing a paleo-geomorphic unit distribution map within the target area, and determining the type of paleo-geomorphic unit where the well is located based on the paleo-geomorphic unit distribution map within the target area;

[0014] Based on the well logging data, the oil and water layers are preliminarily identified, and the oil and water layers are divided to obtain the preliminary identification results of the oil layer;

[0015] According to the type of paleo-geomorphic unit where the well is located, the geomorphic characteristics of the paleo-geomorphic unit are obtained, and the preliminary identification result of the oil layer is optimized to obtain the optimized identification result of the oil layer.

[0016] On the basis of the above technical solution, the present invention can also make the following improvements.

[0017] Optionally, reconstructing a paleo-geomorphological feature map of the target area based on the collected geological sedimentary environment information of the target area, and determining the type of paleo-geomorphological unit where the well is located based on a paleo-geomorphological unit distribution map within the target area, includes:

[0018] Obtain geological sedimentary environment information, tectonic background and paleo-geomorphological characteristics of the target area;

[0019] Reconstructing the paleo-geomorphic features of the target area based on the geological sedimentary environment information, tectonic background, paleo-geomorphic features of the target area and the three-dimensional seismic data of the target area;

[0020] Analyze paleo-geomorphological types in different geological periods based on geological principles and draw paleo-geomorphological unit distribution maps;

[0021] According to the paleogeomorphic unit distribution map, each paleogeomorphic unit in the target area is determined, and the type of paleogeomorphic unit at the drilling location is obtained.

[0022] Optionally, the paleo-geomorphological unit types include at least terraces, slopes and river mounds.

[0023] Optionally, the preliminary identification of the oil and water layers based on the well logging data and the division of the oil and water layers to obtain the preliminary oil layer identification results include:

[0024] Preliminary division of oil and water layers based on drilling and logging data;

[0025] Based on the changing characteristics of the logging data curve, the distribution of oil and water layers is preliminarily determined;

[0026] Determine the lithology of oil and water layers based on core data and well logging data;

[0027] By measuring the porosity and saturation of different lithologic layers, the interface between the oil layer and the water layer is determined, and the oil layer is preliminarily identified;

[0028] Based on the preliminary oil layer identification results, the potential oil layer areas in the target area are marked.

[0029] Optionally, the obtaining of geomorphological features of the paleomorphological unit according to the type of paleomorphological unit where the well is logged, and optimizing the preliminary oil layer identification result to obtain the optimized oil layer identification result includes:

[0030] Analyze the geomorphic features of the paleomorphic unit according to the type of the drilling well, and determine whether the initially identified oil reservoir area is in an area with favorable reservoir formation conditions;

[0031] If the initially identified oil layer area is located in a paleogeomorphological unit with high porosity and good sealing properties, and is determined to be in an area with favorable reservoir formation conditions, then the reliability of the initial oil layer identification result is high and no optimization is required;

[0032] On the contrary, if the initially identified oil layer area is in an area with unfavorable reservoir formation conditions, the initial identification result of the oil layer needs to be optimized;

[0033] The optimization of the preliminary oil layer identification results includes:

[0034] Based on the geomorphological characteristics of the paleo-geomorphological unit where the well is located as a constraint, the preliminarily identified oil layer area is screened and used as the optimized oil layer identification result.

[0035] Optionally, the method of screening the initially identified oil layer area based on the geomorphological characteristics of the paleo-geomorphological unit where the well is located as a constraint, as the result of optimized oil layer identification, includes:

[0036] Based on the geomorphological constraints of the paleo-geomorphological unit where the well is located, the spatial distribution of the oil layer area and its accumulation conditions are confirmed, and the effective reservoir range of the oil layer area is delineated.

[0037] According to a second aspect of the present invention, there is provided an oil layer logging identification system based on paleo-geomorphological analysis constraints, comprising:

[0038] a determination module for reconstructing a paleo-geomorphic feature map of the target area based on the collected geological sedimentary environment information of the target area, drawing a paleo-geomorphic unit distribution map within the target area, and determining the type of paleo-geomorphic unit where the well is located based on the paleo-geomorphic unit distribution map within the target area;

[0039] The preliminary identification module is used to perform preliminary identification of oil and water layers based on well logging data, and to divide the oil layer and water layer to obtain preliminary identification results of the oil layer;

[0040] The optimization identification module is used to obtain the geomorphic characteristics of the paleomorphic unit according to the type of the paleomorphic unit where the well is located, optimize the preliminary identification result of the oil layer, and obtain the optimized identification result of the oil layer.

[0041] The application provides an oil layer logging identification method and system based on paleogeomorphology analysis constraint. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 A flow chart of an oil layer logging identification method based on paleogeomorphology analysis constraint is provided in the application.

[0043] Figure 2 A paleogeomorphology unit distribution map of a reconstructed target area is provided.

[0044] Figure 3 A boundary division result diagram of an oil layer and a water layer is provided.

[0045] Figure 4 A single well logging interpretation result diagram after paleogeomorphology unit constraint is provided.

[0046] Figure 5 A structure diagram of an oil layer logging identification system based on paleogeomorphology analysis constraint is provided in the application. DETAILED DESCRIPTION

[0047] To make the objectives, technical solutions and advantages of the embodiments of the application clearer, the technical solutions in the embodiments of the application will be described below in connection with the drawings in the embodiments of the application. Obviously, the described embodiments are some but not all of the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without any creative work fall within the protection scope of the application. In addition, the technical features in each embodiment or in a single embodiment provided in the application can be combined with each other to form a feasible technical solution, and such combination is not subject to the sequence order and / or structure mode, but should be based on the feasibility for those of ordinary skill in the art. When the combination of technical solutions appears contradictory or unfeasible, it should be considered that the combination of technical solutions does not exist and is not within the protection scope of the application.

[0048] In oil reservoir exploration, well logging technology is a commonly used detection method for identifying oil and water layers. However, in complex geological environments, especially in oil reservoir development areas controlled by paleogeomorphology, traditional well logging identification methods often have low accuracy due to changes in geological conditions or stratum heterogeneity, and are prone to misidentification or missed identification. In oil reservoir development areas controlled by paleogeomorphology, different types of paleogeomorphology have a significant control over the distribution of oil layers, often leading to increased complexity of the oil layers. Therefore, a new oil layer logging identification method is urgently needed that can incorporate paleogeomorphic feature constraints to improve the accuracy and reliability of logging identification, especially in oil reservoir areas controlled by paleogeomorphology.

[0049] Figure 1 The present invention provides a flow chart of an oil layer logging identification method based on paleo-geomorphological analysis constraints, such as Figure 1 As shown, the method includes:

[0050] Step 1: Reconstruct the paleo-geomorphic characteristic map of the target area based on the acquired geological sedimentary environment information of the target area, draw a paleo-geomorphic unit distribution map in the target area, and determine the type of paleo-geomorphic unit where the well is located based on the paleo-geomorphic unit distribution map in the target area.

[0051] In a possible embodiment of the present invention, reconstructing a paleo-geomorphological characteristic map of the target area based on the collected geological sedimentary environment information of the target area, and determining the type of paleo-geomorphological unit where the well is located based on the paleo-geomorphological unit distribution map in the target area, includes:

[0052] Obtain geological sedimentary environment information, tectonic background and paleogeomorphic characteristics of the target area; reconstruct the paleogeomorphic characteristics of the target area based on the geological sedimentary environment information, tectonic background, paleogeomorphic characteristics and three-dimensional seismic data of the target area; analyze the paleogeomorphic types of different geological periods based on geological principles and draw a paleogeomorphic unit distribution map; determine the various paleogeomorphic units in the target area based on the paleogeomorphic unit distribution map, and obtain the paleogeomorphic unit type at the drilling location.

[0053] It is understood that the paleo-geomorphology of the target area is restored by using geological exploration data, seismic exploration data, paleo-geomorphological data and historical data to reconstruct the paleo-geomorphological distribution characteristics in the area. The specific operations of this step are as follows:

[0054] Data collection: The sedimentary environment, tectonic setting and paleo-geomorphological characteristics of the target area are obtained through drilling data, 3D seismic exploration data, core analysis and geological historical information.

[0055] Paleogeomorphological reconstruction: Reconstructing the paleogeomorphic features of the target area based on geological background information (e.g., changes in the sedimentary environment, paleo-river course orientation, etc.) combined with existing 3D seismic data. Using geological principles, we analyze paleogeomorphic types from different geological periods (e.g., incised valleys, alluvial fans, paleo-lakes, etc.) and create a distribution map of paleogeomorphic units.

[0056] Paleomorphic unit identification: Based on the restored paleomorphic features, the paleomorphic units of the target area are determined. The paleomorphic unit where each well is located needs to be accurately identified and calibrated to provide geological background support for subsequent oil layer identification.

[0057] Step 2: Based on the well logging data, the oil and water layers are preliminarily identified, and the oil and water layers are divided to obtain the preliminary identification results of the oil layer.

[0058] In a possible embodiment of the present invention, the oil and water layers are preliminarily identified based on the logging data, and the oil layers and water layers are divided to obtain a preliminary oil layer identification result, including: preliminarily dividing the oil and water layers based on the drilling and logging data; preliminarily determining the distribution of the oil layers and water layers based on the changing characteristics of the logging data curve; making lithologic judgments on the oil layers and water layers based on the core data and the logging data; determining the interface between the oil layer and the water layer by measuring the porosity and saturation of different lithologic layers, and preliminarily identifying the oil layer; and calibrating the potential oil layer area in the target area based on the preliminary oil layer identification result.

[0059] In this step, the oil and water layers are preliminarily identified in combination with the well logging data. The specific operations are as follows:

[0060] Well logging data analysis: Qualitative and quantitative analysis of drilling and logging data (such as resistivity, gamma rays, acoustic transit time, density, and impedance) allows for preliminary delineation of oil and water layers. The distribution of oil and water layers is then determined based on the changing characteristics of the logging curves (e.g., high resistivity, low gamma rays).

[0061] Lithology and fluid property analysis: Combining core data and well logging data, we determine the lithology of oil and water layers. By measuring the porosity, saturation, and other physical properties of different lithologic layers, we can further determine the interface between the oil and water layers and obtain preliminary identification results for the oil and water layers.

[0062] Preliminary oil and water layer division: Based on the preliminary results of oil and water layer identification, potential oil layer areas are marked to provide a basis for subsequent analysis.

[0063] Step 3: According to the type of paleo-geomorphic unit where the well is located, the geomorphic characteristics of the paleo-geomorphic unit are obtained, and the preliminary identification result of the oil layer is optimized to obtain the optimized identification result of the oil layer.

[0064] In a possible embodiment of the present invention, the method of obtaining the geomorphological characteristics of the paleomorphological unit according to the type of the paleomorphological unit where the well is located, optimizing the preliminary oil layer identification result, and obtaining the optimized oil layer identification result includes:

[0065] According to the type of paleogeomorphic unit where the drilling is located, the geomorphic characteristics of the paleogeomorphic unit are analyzed to determine whether the preliminarily identified oil layer area is in an area with favorable reservoir conditions; if the preliminarily identified oil layer area is located in a paleogeomorphic unit with higher porosity and better sealing, it is determined that the preliminarily identified oil layer area is in an area with favorable reservoir conditions, and the reliability of the preliminarily identified oil layer identification result is high and no optimization is required; on the contrary, if the preliminarily identified oil layer area is in an area with unfavorable reservoir conditions, the preliminarily identified oil layer identification result needs to be optimized; wherein, based on the geomorphic characteristics of the paleogeomorphic unit where the drilling is located as a constraint, the preliminarily identified oil layer area is screened as the optimized oil layer identification result.

[0066] Among them, further paleo-geomorphic unit analysis is carried out on the oil layer area that has been initially identified, and the characteristics of the paleo-geomorphic units are combined to optimize the oil layer identification. The specific steps are as follows:

[0067] Analysis of the relationship between paleo-geomorphic units and oil reservoirs: Analyze the impact of paleo-geomorphic units on oil reservoirs based on the type of paleo-geomorphic units and the development conditions of oil reservoirs. Different types of paleo-geomorphic units often have different sedimentary characteristics and reservoir properties, which directly affect the distribution and reservoir performance of oil reservoirs.

[0068] For example, inter-river hill paleo-geomorphology of incised river valleys and slope areas on both sides of the valley usually have good conditions for reservoir development, while in other types of paleo-geomorphological units, the distribution of oil layers may be less.

[0069] Favorable reservoir conditions determination: Analyze paleo-geomorphic units to determine whether the reservoir is located in an area with favorable reservoir conditions. If the reservoir is located in a paleo-geomorphic unit with high porosity and good sealing, the identification result is highly reliable, and there is no need to optimize the initial reservoir identification results. Conversely, if the reservoir is located in a less favorable paleo-geomorphic unit, further analysis of its reservoir potential is required.

[0070] Constraints of paleogeomorphology on oil layer identification: Combined with the characteristics of paleogeomorphic units, the oil layer areas that have been preliminarily identified are constrained to screen out the oil layer areas with the greatest development potential and economic value.

[0071] Finally, after paleo-geomorphic unit analysis and reservoir optimization identification, the final logging interpretation of the reservoir is performed based on the constraints of the paleo-geomorphic analysis. The specific operations are as follows:

[0072] Reservoir interpretation optimization: By combining the preliminary identification results of oil and water layers with the analysis results of paleo-geomorphic units, we can further optimize the identification of reservoirs. By using the results of paleo-geomorphic analysis constraints, we can correct potential errors in traditional logging identification methods and ensure that the final reservoir distribution results are more accurate.

[0073] Confirmation of oil layer distribution and reservoir formation conditions: Based on paleogeomorphic constraints, the spatial distribution of oil layers and their reservoir formation conditions are determined, further delineating the effective reservoir range. This stage focuses on confirming whether the oil layer has sufficient reservoir capacity and whether the conditions for oil and gas accumulation exist, ensuring a solid foundation for subsequent development.

[0074] The following is a specific implementation case of the oil layer logging identification method based on paleo-geomorphological analysis constraints of the present invention, as well as the effects and results after the implementation of the method.

[0075] This case study was conducted in a paleovalley reservoir development area within an oilfield. The target area, a reservoir controlled by paleo-geomorphology, features complex subsurface structures and intricate patterns of oil and water distribution. Traditional well logging methods for identifying reservoirs face challenges in this area. The complex geological conditions and limitations of traditional methods result in low reservoir identification accuracy.

[0076] Case Study: A new oil layer logging identification method provided by the present invention improves the accuracy of oil layer identification, reduces misidentification and missed identification, improves reservoir exploration efficiency, and provides more reliable data support for subsequent development decisions.

[0077] The implementation steps are as follows:

[0078] Step 1: Paleogeomorphological restoration and determination of paleogeomorphological units in the target area.

[0079] Data Collection: Detailed sedimentary environment information for the target area was collected through drilling data, 3D seismic data, core analysis, and geological historical data. The reservoir sedimentary history in this area is complex, with a history of tectonic uplift and valley incision.

[0080] Paleomorphological restoration: Based on the sedimentological and tectonic background of the target area, the paleomorphological characteristic map of the area was reconstructed using the paleomorphological restoration method. Figure 2 By analyzing drilling data and 3D seismic data, paleo-geomorphic units such as paleo-river channels, terraces, slopes, and inter-fluvial hills were identified, and a distribution map of paleo-geomorphic units in the region was drawn.

[0081] Identification of paleomorphic units: Based on the restored paleomorphic feature map, the paleomorphic unit types of each well were identified. The paleomorphic units of terraces, slopes, and inter-fluvial hills, which are closely related to the distribution of oil reservoirs, were particularly identified.

[0082] Step 2: Preliminary identification of oil and water layers.

[0083] Logging data analysis: Use conventional logging data (such as resistivity, gamma ray, acoustic time difference, etc.) to preliminarily identify oil and water layers. Through the analysis of logging curves, the boundaries of oil and water layers are preliminarily demarcated, and the division results can be seen in Figure 3 , and several potential oil layer regions are identified.

[0084] Lithology and fluid property analysis: Through comparison with core data, the lithological characteristics of oil and water layers are further confirmed. The thickness and saturation of oil layers are preliminarily determined by using oil and gas saturation calculation.

[0085] Step 3: Paleogeomorphology unit analysis and oil layer identification optimization.

[0086] Paleogeomorphology unit and oil layer relationship analysis: Combined with the characteristics of the paleogeomorphology unit, the influence of the paleogeomorphology unit on the development of the oil layer is analyzed. It is found that in the downcutting valley area, the oil layer is mainly distributed in the slope of the paleochannel and the interchannel hill, and these areas have high porosity and good sealing property. In contrast, the main river channel has poor reservoir conditions.

[0087] Favorable reservoir condition determination: Through paleogeomorphology analysis, it is determined that the paleochannel area is the most favorable reservoir unit, and other paleogeomorphology units have poor reservoir properties and poor sealing properties, which need further attention.

[0088] Optimization of oil layer identification: According to the constraint of the paleogeomorphology unit, the identification of the oil layer is further optimized, the distribution range of the main oil layer is determined, the favorable paleogeomorphology development area is focused on, and the non-oil layer area is excluded, avoiding the misidentification and omission in the traditional method.

[0089] Step 4: Final oil layer logging interpretation under the constraint of paleogeomorphology analysis.

[0090] According to the final oil layer logging interpretation results under the constraint of paleogeomorphology analysis, single well oil layer interpretation results are derived and a database is formed, wherein the single well oil layer interpretation results can be seen in Figure 4 .

[0091] Referring to Figure 5 , an oil layer logging identification system based on the constraint of paleogeomorphology analysis is provided, and the system comprises:

[0092] The determination module 501 is configured to reconstruct the paleogeomorphology feature map of the target area according to the collected geological sedimentary environment information of the target area, draw the paleogeomorphology unit distribution map in the target area, and determine the type of the paleogeomorphology unit where the well is located according to the paleogeomorphology unit distribution map in the target area.

[0093] The preliminary identification module 502 is configured to preliminarily identify oil and water layers according to logging data, divide oil and water layers, and obtain preliminary identification results of oil layers.

[0094] The optimization identification module 503 is configured to obtain the landform features of the paleogeomorphology unit according to the type of the paleogeomorphology unit in which the well logging is located, optimize the preliminary identification result of the oil layer, and obtain an optimized identification result of the oil layer.

[0095] It can be understood that the oil layer well logging identification system based on paleogeomorphology analysis constraint provided by the present application corresponds to the oil layer well logging identification method based on paleogeomorphology analysis constraint provided by the above-mentioned embodiments, and the related technical features of the oil layer well logging identification system based on paleogeomorphology analysis constraint can be referred to the related technical features of the oil layer well logging identification method based on paleogeomorphology analysis constraint, which will not be described here.

[0096] The oil layer well logging identification method and system based on paleogeomorphology analysis constraint provided by the embodiments of the present application have the following beneficial effects:

[0097] (1) Improve the accuracy of oil layer identification: By introducing the paleogeomorphology analysis constraint, the oil layer affected by the paleogeomorphology can be more accurately identified, and the misidentification and missed identification situations can be reduced, especially in the undercut valley and alluvial fan regions with complex paleogeomorphology.

[0098] (2) Enhance the reliability of oil layer identification: The paleogeomorphology analysis provides geological background information for oil layer identification, ensures that the oil layer identification result is consistent with the geological conditions, and improves the reliability and stability of the oil layer identification.

[0099] (3) Suitable for complex geological environment: The method is particularly suitable for regions with complex oil layer distribution and strong influence of paleogeomorphology unit, and can provide more accurate oil layer identification results for exploration personnel, avoiding the uncertainty of traditional methods in complex geological environment.

[0100] (4) Optimize oil and gas exploration decision: By accurately identifying the oil layer and its reservoir forming conditions, more scientific basis can be provided for oilfield development, optimization of exploration decision, and improvement of oil and gas exploration and development efficiency.

[0101] It should be noted that in the above embodiments, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0102] Although the preferred embodiments of the present application have been described, those skilled in the art can make further changes and modifications to these embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0103] Obviously, many modifications and variations of the present application are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A method for oil layer logging identification based on paleo-geomorphological analysis constraints, characterized in that: include: Reconstructing a paleo-geomorphic feature map of the target area based on the acquired geological sedimentary environment information of the target area, drawing a paleo-geomorphic unit distribution map within the target area, and determining the type of paleo-geomorphic unit where the well is located based on the paleo-geomorphic unit distribution map within the target area; Based on the well logging data, the oil and water layers are preliminarily identified, and the oil and water layers are divided to obtain the preliminary identification results of the oil layer; According to the type of paleo-geomorphic unit where the well is located, the geomorphic features of the paleo-geomorphic unit are obtained, and the preliminary identification result of the oil layer is optimized to obtain an optimized identification result of the oil layer; The method of obtaining the geomorphic features of the paleomorphic unit according to the type of the paleomorphic unit where the well is located, optimizing the preliminary oil layer identification result, and obtaining the optimized oil layer identification result includes: Analyze the geomorphic features of the paleomorphic unit according to the type of the drilling well, and determine whether the initially identified oil reservoir area is in an area with favorable reservoir formation conditions; If the initially identified oil layer area is located in a paleogeomorphological unit with high porosity and good sealing properties, and is determined to be in an area with favorable reservoir formation conditions, then the reliability of the initial oil layer identification result is high and no optimization is required; On the contrary, if the initially identified oil layer area is in an area with unfavorable reservoir formation conditions, the initial identification result of the oil layer needs to be optimized; The optimization of the preliminary oil layer identification results includes: Based on the geomorphological characteristics of the paleo-geomorphological unit where the well is located as a constraint, the preliminarily identified oil layer area is screened and used as the optimized oil layer identification result.

2. The oil layer logging identification method according to claim 1, characterized in that: The method of reconstructing a paleo-geomorphological feature map of the target area based on the acquired geological sedimentary environment information of the target area, drawing a paleo-geomorphological unit distribution map within the target area, and determining the type of paleo-geomorphological unit where the well is located based on the paleo-geomorphological unit distribution map within the target area includes: Obtaining geological sedimentary environment information, tectonic background and paleo-geomorphological characteristics of the target area; Reconstructing the paleo-geomorphic features of the target area based on the geological sedimentary environment information, tectonic background, paleo-geomorphic features of the target area and the three-dimensional seismic data of the target area; Analyze the paleo-geomorphic types of different geological periods according to geological principles and draw a distribution map of paleo-geomorphic units in the target area; According to the paleogeomorphic unit distribution map, each paleogeomorphic unit in the target area is determined, and the type of paleogeomorphic unit at the drilling location is obtained.

3. The oil layer logging identification method according to claim 2, characterized in that: The paleo-geomorphic unit types include at least terraces, slopes and inter-river hills.

4. The oil layer logging identification method according to claim 1, characterized in that: The oil and water layers are preliminarily identified based on the well logging data, and the oil and water layers are divided to obtain the preliminary oil layer identification results, including: Preliminarily demarcate the oil and water layers within the target area based on drilling and logging data; Based on the changing characteristics of the logging data curve, the distribution of oil and water layers is preliminarily determined; Determine the lithology of oil and water layers based on core data and well logging data; By measuring the porosity and saturation of different lithologic layers, the interface between the oil layer and the water layer is determined, and the oil layer is preliminarily identified; Based on the preliminary oil layer identification results, the potential oil layer areas in the target area are marked.

5. The oil layer logging identification method according to claim 1, characterized in that: The method of screening the initially identified oil layer area based on the geomorphological characteristics of the paleo-geomorphological unit where the well is located as a constraint and using the optimized oil layer identification result as the result includes: Based on the geomorphological constraints of the paleo-geomorphological unit where the well is located, the spatial distribution of the oil layer area and its accumulation conditions are confirmed, and the effective reservoir range of the oil layer area is delineated.

6. A well logging identification system for oil layers based on paleo-geomorphological analysis constraints, characterized in that: include: a determination module, configured to reconstruct a paleo-geomorphic feature map of the target area based on the acquired geological sedimentary environment information of the target area, draw a paleo-geomorphic unit distribution map within the target area, and determine the type of paleo-geomorphic unit where the well is located based on the paleo-geomorphic unit distribution map within the target area; The preliminary identification module is used to perform preliminary identification of oil and water layers based on well logging data, and to divide the oil layer and water layer to obtain preliminary identification results of the oil layer; An optimization identification module is used to obtain the geomorphic characteristics of the paleomorphic unit according to the type of the paleomorphic unit where the well is located, optimize the preliminary identification result of the oil layer, and obtain an optimized identification result of the oil layer; The method of obtaining the geomorphic features of the paleomorphic unit according to the type of the paleomorphic unit where the well is located, optimizing the preliminary oil layer identification result, and obtaining the optimized oil layer identification result includes: Analyze the geomorphic features of the paleomorphic unit according to the type of the drilling well, and determine whether the initially identified oil reservoir area is in an area with favorable reservoir formation conditions; If the initially identified oil layer area is located in a paleogeomorphological unit with high porosity and good sealing properties, and is determined to be in an area with favorable reservoir formation conditions, then the reliability of the initial oil layer identification result is high and no optimization is required; On the contrary, if the initially identified oil layer area is in an area with unfavorable reservoir formation conditions, the initial identification result of the oil layer needs to be optimized; The optimization of the preliminary oil layer identification results includes: Based on the geomorphological characteristics of the paleo-geomorphological unit where the well is located as a constraint, the preliminarily identified oil layer area is screened and used as the optimized oil layer identification result.

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