A method for selecting formations and placing wells to improve the drilling rate of interbedded shale oil.

Abstract

This invention belongs to the field of oilfield development technology, specifically relating to a method for selecting layers and placing wells to improve the drilling rate of interlayered shale oil. This invention establishes a detailed regional isochronous stratigraphic correlation framework, establishes reservoir sedimentary microfacies logging interpretation templates and delineates reservoir distribution plans under the control of each isochronous stratigraphic correlation framework, establishes sedimentary boundary identification templates that match regional seismic and logging interpretations, corrects reservoir planar distribution characteristics and vertical superposition relationships, establishes single-layer-level three-dimensional stratigraphic-structural models of reservoirs, establishes three-dimensional distribution models of reservoirs with different sedimentary genesis, and optimizes the location of large-scale shale oil well sites. Furthermore, it optimizes the azimuth and length of horizontal wells based on sand body size and dominant distribution direction. This improves the drilling rate of interlayered shale oil horizontal wells while maximizing reserve utilization, and has achieved good field implementation results.

Description

Technical Field

[0001] This invention belongs to the field of oilfield development technology, specifically relating to a method for selecting layers and placing wells to improve the drilling rate of interlayer shale oil. Background Technology

[0002] China has abundant continental shale oil resources, with technically recoverable resources estimated at approximately 44.8 × 10⁻⁶. 8 With reserves far exceeding those of conventional oil, China's shale oil reserves and production are second only to the United States and Russia, making it a crucial strategic replacement area for increasing crude oil production. The oil-bearing formation encounter rate is the main factor affecting the production of horizontal wells in continental shale oil. Interbedded shale oil, exemplified by the Ordos Basin, generally employs a large-platform deployment approach to achieve a single target deployment and overall utilization. Continental interbedded shale oil, supplied by multiple types of sources including terrestrial, endogenous, and volcanic origins, has formed complex source-reservoir combinations, characterized by multiple sweet spots vertically, rapid horizontal variations, and small distribution scale. As shale oil development deepens, interbedded shale oil reservoirs are becoming increasingly complex.

[0003] Currently, the deployment of interlayer shale oil is mainly based on a large-platform well layout method with fixed horizontal well orientation (vertical principal stress) without considering the genesis and distribution characteristics of underground sand bodies. This has led to problems such as unstable horizontal well drilling rate and ineffective utilization of the prime reservoir in the target area. How to improve the horizontal well drilling rate through high-quality integrated well layout has become an urgent technical problem to be solved. Summary of the Invention

[0004] This invention provides a method for selecting and placing wells to improve the drilling rate of interbedded shale oil. Its purpose is to provide a method for selecting and placing wells to effectively improve the drilling rate of horizontal wells in interbedded shale oil while maximizing the utilization of reserves.

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

[0006] A method for selecting formations and placing wells to improve the drilling success rate of interbedded shale oil fields includes the following steps:

[0007] Step 1: Establish a detailed isochronous stratigraphic correlation framework for the region;

[0008] Step 2: Establish a reservoir sedimentary microfacies logging interpretation template and draw a reservoir distribution plan under the control of each grid frame of isochronous stratigraphy.

[0009] Step 3: Establish a sedimentary boundary identification template that matches regional seismic and well logging interpretations, and correct the planar distribution characteristics and vertical superposition relationships of reservoirs;

[0010] Step 4: Establish a three-dimensional stratigraphic-structural model of a single-layer reservoir;

[0011] Step 5: Establish three-dimensional distribution models of reservoirs with different sedimentary genesis and obtain three-dimensional spatial quantitative parameters of reservoirs with different genesis.

[0012] Step 6: Based on the three-dimensional spatial quantitative parameters of reservoirs of different origins, optimize the location of large shale oil well sites, optimize the orientation of horizontal wells, and select target layers for drilling.

[0013] The method for establishing a detailed isochronous stratigraphic framework in step one is to establish a longitudinal and transverse framework correlation profile around the dominant development area of ​​interlayered shale oil reservoirs; and to use the seismic wave peak phase axis to indicate stable and continuous high gamma mudstone, and to perform well-seismic calibration on stable high gamma mudstone that is simultaneously developed on well logging, in order to establish a detailed isochronous stratigraphic framework.

[0014] The method for establishing a reservoir sedimentary microfacies logging interpretation template in step two and outlining the reservoir distribution plan under the control of each framework of isochronous stratigraphy is through core-logging calibration. Using core analysis and field profile observation, the lithological characteristics, sedimentary structures, sand body thickness, rhythm, electrical characteristics, and sedimentary mechanism microfacies of the main channel, tributary channel, main body of the lobe, lateral edge of the lobe, slump, and sedimentary bodies between channels or lobes in the study area are identified. A single sand body sedimentary genesis logging response template is established, and through single-well sand body genesis analysis, the reservoir distribution plan under the control of each framework of isochronous stratigraphy is outlined.

[0015] The method for establishing a sedimentary boundary identification template that matches regional seismic and well logging interpretation in step three is as follows:

[0016] The first step is to obtain 3D seismic inversion slices and reservoir configuration materials;

[0017] The second step is to determine the boundaries and orientation of the reservoir by analyzing the three-dimensional seismic inversion slices and reservoir configuration.

[0018] The third step is to establish a sedimentary boundary identification template that matches the regional seismic and well logging interpretation, based on step two.

[0019] The method for establishing a single-layer-level reservoir three-dimensional stratigraphic-structural model in step four is as follows:

[0020] The first step is to establish a velocity field based on the unified time-depth relationship across the entire region;

[0021] The second step is to convert the seismic horizons in the time domain into those in the depth domain.

[0022] The third step is to establish a top surface model of each reservoir using the seismic tectonic surface of the reservoir top surface as a constraint, and to perform layer interpolation based on the thickness to establish a single-layer level three-dimensional stratigraphic-tectonic model of the reservoir.

[0023] The method for establishing three-dimensional distribution models of reservoirs with different sedimentary origins in step five is as follows: Based on the three-dimensional stratigraphic-structural model of the reservoir established in step four, interlayer reservoir models of different origins are used as modeling targets. The models are sequentially embedded into the mudstone and shale background facies model. The microstructures of the top surface of different reservoirs are read according to the single-well logging data. Under the control of the configuration plane and the thickness of the reservoir, the low-surface structure of the reservoir is calculated to obtain the spatial distribution range of the reservoir. The reservoir is then gridded according to the spatial range using mapping software to obtain three-dimensional distribution models of reservoirs with different sedimentary origins.

[0024] The drawing software used is Direct.

[0025] The three-dimensional spatial quantitative parameters of reservoirs of different origins in step five include reservoir thickness, length, width, dominant distribution direction, and planar spacing.

[0026] The method for optimizing the location of large shale oil well sites in step six, and selecting target layers for drilling, utilizes the three-dimensional distribution models of reservoirs of different sedimentary origins established in step five. This optimization involves determining the location of the large shale oil well sites and the orientation of horizontal wells based on the dominant distribution direction and planar spacing of different reservoirs. Target layers are selected and horizontal well lengths are optimized based on the thickness and length of the sand bodies. Specifically: for narrow, strip-shaped reservoirs, the well site is optimized to be located in the middle of the reservoir, with the horizontal well orientation parallel to the reservoir's distribution direction; for two adjacent but unconnected reservoirs with a wide distribution range, the well site is optimized to be located between the two reservoirs; vertically, quantitative parameters of different reservoirs are obtained based on the three-dimensional distribution models of reservoirs of the same sedimentary origin, and drilling is performed on layers with stable distribution along the horizontal well extension direction; for layers with unstable distribution, the overall drilling rate is improved by shortening the horizontal well length.

[0027] Beneficial effects:

[0028] 1. This invention establishes a detailed regional isochronous stratigraphic correlation framework, establishes reservoir sedimentary microfacies logging interpretation templates and delineates reservoir distribution planar maps under the control of each isochronous stratigraphic correlation framework, establishes sedimentary boundary identification templates that match regional seismic and logging interpretations, corrects reservoir planar distribution characteristics and vertical superposition relationships, establishes single-layer-level three-dimensional stratigraphic-structural models of reservoirs, establishes three-dimensional distribution models of reservoirs with different sedimentary genesis, and optimizes the location of large-scale shale oil well sites. Furthermore, it optimizes the azimuth and length of horizontal wells based on the size of sand bodies and their dominant distribution direction. Under the premise of maximizing reserve utilization, it improves the drilling rate of interlayered shale oil horizontal wells and achieves good field implementation results.

[0029] 2. This invention has important guiding significance for the efficient development of interbedded shale oil in China. Referring to this technology can effectively improve the drilling rate of interbedded shale oil, and at the same time, it can also analyze the reasons for the failure of completed horizontal wells by looking back.

[0030] 3. The drilling rate of oil-bearing formations in wells deployed using the technical solution of this invention is generally close to 90%, which is 10% higher than before.

[0031] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a flowchart of the present invention;

[0034] Figure 2 This is the well-seismic correlation isochronous stratigraphic framework of the Qingcheng South Block in a specific embodiment of the present invention;

[0035] Figure 3 This is a template for interpreting the main waterway of sedimentary microfacies logging in the Qingcheng South Block in a specific embodiment of the present invention;

[0036] Figure 4 This is a template for interpreting sedimentary microfacies logging channels in the Qingcheng South Block in a specific embodiment of the present invention;

[0037] Figure 5 This is the template for interpreting the main body of the sedimentary microfacies logging leaf in the Qingcheng South Block in a specific embodiment of the present invention;

[0038] Figure 6 This serves as a template for interpreting the lateral margins of the sedimentary microfacies logging leaf in the Qingcheng South Block in a specific embodiment of the present invention.

[0039] Figure 7 This serves as a template for interpreting sedimentary microfacies logging collapse bodies in the Qingcheng South Block, as described in a specific embodiment of the present invention.

[0040] Figure 8 This serves as an interpretation template for the interchannel / leaf interchannel of sedimentary microfacies logging in the Qingcheng South Block in a specific embodiment of the present invention;

[0041] Figure 9 This is a reservoir boundary identification template depicted by a combination of well and seismic analysis in a specific embodiment of the present invention.

[0042] Figure 10 This is a schematic diagram of the reservoir boundary identification results under the combined well-seismic characterization in a specific embodiment of the present invention;

[0043] Figure 11 This is a structural model of the Qingcheng South Plate 15 area in a specific embodiment of the present invention;

[0044] Figure 12 This is a schematic diagram showing the spatial distribution of reservoirs with different sedimentary origins, based on the three-dimensional phase control modeling results in a specific embodiment of the present invention.

[0045] Figure 13 This is a schematic diagram showing the optimized orientation and length of the horizontal well of the experimental platform in a specific embodiment of the present invention;

[0046] Figure 14 This is a schematic diagram of the large platform well site and stratigraphic optimization in a specific embodiment of the present invention. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0048] Example 1:

[0049] according to Figure 1 The method for selecting formations and placing wells to improve the drilling success rate of interbedded shale oil fields, as shown, includes the following steps:

[0050] Step 1: Establish a detailed isochronous stratigraphic correlation framework for the region;

[0051] Step 2: Establish a reservoir sedimentary microfacies logging interpretation template and draw a reservoir distribution plan under the control of each grid frame of isochronous stratigraphy.

[0052] Step 3: Establish a sedimentary boundary identification template that matches regional seismic and well logging interpretations, and correct the planar distribution characteristics and vertical superposition relationships of reservoirs;

[0053] Step 4: Establish a three-dimensional stratigraphic-structural model of a single-layer reservoir;

[0054] Step 5: Establish three-dimensional distribution models of reservoirs with different sedimentary genesis and obtain three-dimensional spatial quantitative parameters of reservoirs with different genesis.

[0055] Step 6: Based on the three-dimensional spatial quantitative parameters of reservoirs of different origins, optimize the location of large shale oil well sites, optimize the orientation of horizontal wells, and select target layers for drilling.

[0056] This invention improves the drilling rate of interbedded shale oil horizontal wells while maximizing the utilization of reserves, and achieves good field implementation results.

[0057] Example 2:

[0058] according to Figure 1 The layer selection and well placement method for improving the drilling rate of interlayered shale oil reservoirs, as shown, differs from Example 1 in that: the method for establishing a detailed isochronous stratigraphic correlation framework in step one involves creating a longitudinal and transverse framework correlation profile around the dominant development area of ​​the interlayered shale oil reservoir; using seismic peak phase axes to indicate stable and continuous high-gamma mudstone, and simultaneously stable high-gamma mudstone found on well logging, well-seismic calibration is performed to establish a detailed isochronous stratigraphic framework. This avoids the situation where low drilling rates of designed horizontal wells occur due to interlayer penetration phenomena.

[0059] Furthermore, the method for establishing a reservoir sedimentary microfacies logging interpretation template in step two and outlining the reservoir distribution plan under the control of each framework of isochronous stratigraphy is to use core-logging calibration, core analysis, and field profile observation to clarify the lithological characteristics, sedimentary structures, sand body thickness, rhythm, electrical characteristics, and sedimentary mechanism microfacies of the main channels, tributaries, main bodies of lobes, lateral margins of lobes, slumps, and sediments between channels or lobes in the study area. A single sand body sedimentary genesis logging response template is then established, and through single-well sand body genesis analysis, a reservoir distribution plan under the control of each framework of isochronous stratigraphy is outlined.

[0060] Furthermore, the method for establishing a sedimentary boundary identification template that matches regional seismic and well logging interpretation in step three is as follows:

[0061] The first step is to obtain 3D seismic inversion slices and reservoir configuration materials;

[0062] The second step is to determine the boundaries and orientation of the reservoir by analyzing the three-dimensional seismic inversion slices and reservoir configuration.

[0063] The third step is to establish a sedimentary boundary identification template that matches the regional seismic and well logging interpretation, based on step two.

[0064] In practical applications, by establishing sedimentary boundary identification templates that match regional seismic and well logging interpretations, the planar distribution characteristics and vertical stacking relationships of reservoirs are corrected, resulting in higher accuracy in subsequent reservoir selection and well placement.

[0065] Furthermore, the method for establishing a single-layer-level reservoir three-dimensional stratigraphic-structural model in step four is as follows:

[0066] The first step is to establish a velocity field based on the unified time-depth relationship across the entire region;

[0067] The second step is to convert the seismic horizons in the time domain into those in the depth domain.

[0068] The third step is to establish a top surface model of each reservoir using the seismic tectonic surface of the reservoir top surface as a constraint, and to perform layer interpolation based on the thickness to establish a single-layer level three-dimensional stratigraphic-tectonic model of the reservoir.

[0069] Subsequently, based on the established three-dimensional stratigraphic-structural model of the reservoir, interlayer reservoir models of different genesis were used as modeling targets. The models were sequentially embedded into the mudstone and shale background facies model. Microstructures on the top surface of different reservoirs were read based on single-well logging data. Under the control of the configuration plane and reservoir thickness, the low-surface structure of the reservoir was calculated, thereby obtaining the spatial distribution range of the reservoir. The reservoir was then gridded according to the spatial range using mapping software to obtain three-dimensional distribution models of reservoirs of different sedimentary genesis.

[0070] The drawing software used is Direct. Direct is an existing technology. In specific applications, other drawing software can also be used.

[0071] Furthermore, the three-dimensional spatial quantitative parameters of reservoirs of different origins in step five include reservoir thickness, length, width, dominant distribution direction, and planar spacing.

[0072] Furthermore, in step six, the method for optimizing the location of large shale oil well sites and selecting target layers for drilling utilizes the three-dimensional distribution models of reservoirs with different sedimentary origins established in step five to optimize the location of large shale oil well sites. Specifically, for narrow, strip-shaped reservoirs, the well site is optimized to be located in the middle of the reservoir, with the horizontal well azimuth parallel to the reservoir's distribution direction. For two adjacent but unconnected reservoirs with a wide distribution area, the well site is optimized to be located in the middle of the two reservoirs, ensuring that the area in front of the target is an ineffective reservoir and reducing the probability of wasting high-quality reserves in the area in front of the target. Vertically, based on the three-dimensional distribution models of reservoirs with the same sedimentary origin, quantitative parameters of different reservoirs are obtained, and drilling is performed on layers with stable distribution along the horizontal well extension direction to improve the drilling success rate. For layers with unstable distribution, the overall drilling success rate is improved by shortening the horizontal well length. Figure 14 As shown.

[0073] This invention has significant guiding significance for the efficient development of interbedded shale oil in China. Referring to this technology can effectively improve the drilling success rate of interbedded shale oil wells, and it also allows for retrospective analysis of the reasons for failed horizontal well completions. Wells deployed using this method generally achieve an oil-bearing formation encounter rate approaching 90%, an improvement of 10% compared to previous methods.

[0074] Example 3:

[0075] The Qingcheng South Block of the Qingcheng Shale Oilfield is located in a slope break zone and gentle slope transition area, where interlayered shale oil reservoirs change rapidly. This invention is used for layer selection and well placement, and the specific procedures are as follows:

[0076] 1. Establish a detailed isochronous stratigraphic correlation framework for the region.

[0077] Previous "accretionary-near-isothickness" stratigraphic alignments could not explain the low encounter rate of sand bodies in horizontal wells along the provenance direction. However, significant progradational seismic reflections are developed along the provenance direction, with peak phase axes indicating stable and continuous high-gamma mudstone, possessing isochronous significance. Through well-seismic correlation, a detailed regional isochronous stratigraphic framework was established. Within this progradational stratigraphic framework, two sedimentary systems—deltaic and lacustrine fan—develop from the lake basin margin to the center. The lacustrine fan system can be further divided into three subenvironments (facies zones): slope, near-bottom, and far-bottom. The sedimentary facies zones of different sand groups gradually advance towards the lake center (e.g., ...). Figure 2 ).

[0078] 2. Establishment of sedimentary microfacies logging interpretation templates and analysis of sedimentary configurations in reservoirs

[0079] Core analysis and field profile observations confirmed that the sedimentary model in the study area was gravity-controlled lobed body deposition. The study area identified the development of main channels, tributaries, lobed bodies, lobed lateral margins, slumps, and interchannel / interlobed sedimentary microfacies. Lithoelectric calibration was performed, and a well-logging interpretation template for sedimentary microfacies was established (see table below). Figures 3-8 ).

[0080]

[0081] 3. Three-dimensional seismic inversion slices and reservoir configuration analysis, sand body boundary characterization

[0082] Seismic inversion was performed using seismic attributes highly correlated with sand thickness. A regional single sand body boundary seismic-well logging identification template was established through a combination of seismic-well logging-actual drilling horizontal well analysis. Figure 9 Based on this, a sedimentary configuration profile of the deployment area was established. Figure 10 ).

[0083] 4. Establish a three-dimensional stratigraphic-structural model of a single-layer reservoir.

[0084] Based on a unified time-depth relationship across the entire region, a velocity field was established, converting the seismic horizon in the time domain into the depth domain. Combining seismic interpretation bedding planes and well-layer data, a structural bedding plane model for the study area was constructed, and adjustments were made to the structural surface based on the logging characteristics of vertical and horizontal wells. Based on the structural bedding plane model and according to the thickness distribution of each individual stratum, a vertical grid was set to obtain the structural-stratigraphic model. (e.g.) Figure 11 )

[0085] 5. Establish three-dimensional distribution models of reservoirs with different sedimentary genesis.

[0086] Based on the three-dimensional stratigraphic-tectonic model of reservoirs, interlayer reservoirs of different genesis are used as modeling targets. The models are sequentially embedded into the mudstone and shale background facies model, and the models are post-processed using human-computer interaction to establish three-dimensional distribution models of reservoirs of different sedimentary genesis. Figure 12 ).

[0087] 6. Well pattern optimization

[0088] The azimuth and length of the horizontal wells on Platform B were optimized using 3D phase control modeling. Currently, two wells have been completed on this platform, with a 90% oil reservoir encounter rate, effectively improving the utilization of reserves. (e.g.) Figure 13 )

[0089] This invention effectively solves the problem of the impact of rapid lateral changes and small distribution scale of reservoirs on the drilling rate of interlayered shale oil, and stabilizes the drilling rate of a single well at over 88%.

[0090] Where there is no conflict, those skilled in the art can combine the relevant technical features in the above examples according to the actual situation to achieve the corresponding technical effects. Specific details of the various combinations will not be elaborated here.

[0091] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0092] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0093] The above description is merely a preferred embodiment of the present invention. The present invention is not limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. Any simple modifications, equivalent variations, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for selecting formations and placing wells to improve the drilling success rate of interbedded shale oil, characterized in that: Includes the following steps: Step 1: Establish a detailed isochronous stratigraphic correlation framework for the region; Step 2: Establish a reservoir sedimentary microfacies logging interpretation template and draw a reservoir distribution plan under the control of each grid frame of isochronous stratigraphy. Step 3: Establish a sedimentary boundary identification template that matches regional seismic and well logging interpretations, and correct the planar distribution characteristics and vertical superposition relationships of reservoirs; Step 4: Establish a three-dimensional stratigraphic-structural model of a single-layer reservoir; Step 5: Establish three-dimensional distribution models of reservoirs with different sedimentary genesis and obtain three-dimensional spatial quantitative parameters of reservoirs with different genesis. Step 6: Based on the three-dimensional spatial quantitative parameters of reservoirs of different origins, optimize the location of large shale oil well sites, optimize the orientation of horizontal wells, and select target layers for drilling; The method for establishing a sedimentary boundary identification template that matches regional seismic and well logging interpretation in step three is as follows: The first step is to obtain 3D seismic inversion slices and reservoir configuration materials; The second step is to determine the boundaries and orientation of the reservoir by analyzing the three-dimensional seismic inversion slices and reservoir configuration. The third step is to establish a sedimentary boundary identification template that matches the regional seismic and well logging interpretation, based on step two. The method for establishing a single-layer-level reservoir three-dimensional stratigraphic-structural model in step four is as follows: The first step is to establish a velocity field based on the unified time-depth relationship across the entire region; The second step is to convert the seismic horizons in the time domain into those in the depth domain. The third step is to establish a top surface model of each reservoir based on the seismic tectonic surface of the reservoir top surface, and to perform layer interpolation according to the thickness to establish a single-layer level three-dimensional stratigraphic-tectonic model of the reservoir. The method for establishing three-dimensional distribution models of reservoirs with different sedimentary origins in step five is as follows: Based on the three-dimensional stratigraphic-structural model of the reservoir established in step four, interlayer reservoir models of different origins are used as modeling targets. The models are sequentially embedded into the mudstone and shale background facies model. The microstructures of the top surface of different reservoirs are read according to the single-well logging data. Under the control of the configuration plane and the thickness of the reservoir, the low-surface structure of the reservoir is calculated to obtain the spatial distribution range of the reservoir. The reservoir is then gridded according to the spatial range using mapping software to obtain three-dimensional distribution models of reservoirs with different sedimentary origins.

2. The method for selecting and placing wells to improve the drilling rate of interbedded shale oil as described in claim 1, characterized in that: The method for establishing a detailed isochronous stratigraphic correlation framework in step one is to establish a longitudinal and transverse framework correlation profile main line around the dominant development area of ​​interlayered shale oil reservoirs. By using the seismic wave peak phase axis to indicate stable and continuous high-gamma mudstone, and the stable high-gamma mudstone that is simultaneously developed on the well log, well-seismic calibration is performed to establish a fine isochronous stratigraphic framework.

3. The method for selecting and placing wells to improve the drilling rate of interbedded shale oil as described in claim 1, characterized in that: The method for establishing a reservoir sedimentary microfacies logging interpretation template in step two and outlining the reservoir distribution plan under the control of each framework of isochronous stratigraphy is through core-logging calibration. Using core analysis and field profile observation, the lithological characteristics, sedimentary structures, sand body thickness, rhythm, electrical characteristics, and sedimentary mechanism microfacies of the main channel, tributary channel, main body of the lobe, lateral edge of the lobe, slump, and sedimentary bodies between channels or lobes in the study area are identified. A single sand body sedimentary genesis logging response template is established, and through single-well sand body genesis analysis, the reservoir distribution plan under the control of each framework of isochronous stratigraphy is outlined.

4. The method for selecting formations and placing wells to improve the drilling rate of interbedded shale oil as described in claim 1, characterized in that: The drawing software used is Direct.

5. The method for selecting and placing wells to improve the drilling rate of interbedded shale oil as described in claim 1, characterized in that: The three-dimensional spatial quantitative parameters of reservoirs of different origins in step five include reservoir thickness, length, width, dominant distribution direction, and planar spacing.

6. The method for selecting formations and placing wells to improve the drilling rate of interbedded shale oil as described in claim 1, characterized in that: The method for optimizing the location of large shale oil well sites in step six, and selecting target layers for drilling, utilizes the three-dimensional distribution models of reservoirs of different sedimentary origins established in step five. This optimization involves adjusting the well site location and horizontal well orientation based on the dominant distribution direction and planar spacing of different reservoirs, and selecting target layers and optimizing horizontal well lengths based on sand body thickness and length. Specifically: for narrow, strip-shaped reservoirs, the well site location is optimized to be in the middle of the reservoir, with the horizontal well orientation parallel to the reservoir's distribution direction; for two adjacent but unconnected reservoirs with a wide distribution range, the well site location is optimized to be in the middle of the two reservoirs; vertically, quantitative parameters of different reservoirs are obtained based on the three-dimensional distribution models of reservoirs of the same sedimentary origin, and drilling is performed on layers with stable distribution along the horizontal well extension direction; for layers with unstable distribution, the overall drilling rate is improved by shortening the horizontal well length.

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