Multi-parameter constrained meandering river single river channel sand body description method and system

Abstract

The invention provides a multi-parameter constrained meandering river single river channel sand body description method and system. The method comprises the steps that fine well seismic calibration is conducted on a target river channel sand body according to geological layering; determining a seismic amplitude energy lower limit threshold value of the target river channel sand body according to the logging parameter data; and according to the fine well seismic calibration of the target river channel sand body, extracting the horizon maximum amplitude attribute to describe the river channel sand body, describing the plane distribution form of the target river channel sand body by using the seismic amplitude energy lower limit threshold value, and determining the boundary of the target river channel sand body. The method comprises the following steps: determining a lower limit value of seismic amplitude energy according to a well logging parameter threshold value of a river channel sand body by utilizing a relationship between various well logging parameters and the seismic amplitude energy, then extracting a maximum amplitude attribute, and describing a minimum cutoff value of the river channel sand body by taking the lower limit value of the seismic amplitude energy as the maximum amplitude attribute, thereby achieving the purpose of accurately describing the river channel sand body.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum exploration and development, and particularly relates to a method and system for characterizing a single channel sand body of a meandering river with multi-parameter constraints. Background Art

[0002] With the advancement of horizontal well drilling technology, the exploration of lithologic oil and gas reservoirs formed by high-quality reservoirs has attracted increasing attention from explorers. This is particularly true for meandering river channel sandstone reservoirs, which offer relatively low exploration and development costs and high exploration results due to their high channel stability, slow lateral migration, relatively simple lithologic assemblage, mud-in-sand deposits, distinct electrical and physical properties between the reservoir sand bodies and the surrounding rocks, good reservoir physical properties, and great thickness. However, due to the complexity of meandering river formation and the variability of its direction, it is difficult to effectively control and predict its direction and distribution patterns through drilling alone. Therefore, it is necessary to fully utilize the lateral continuity advantage of seismic data and combine well and seismic data to predict and characterize river channel sand bodies.

[0003] The investigation found that previous researchers used various seismic attributes, especially amplitude attributes, to qualitatively describe the planar distribution of meandering river channel sand bodies. However, when using seismic amplitude attributes to describe river channel sand bodies, the amplitude value is not certain, varies from person to person, and is highly random. Therefore, the results of descriptions by different people are different. The river channel boundaries may be wide or narrow, the river channel may be relatively weak, and the river channel may exist or not. There is no certainty. Summary of the Invention

[0004] To address the above problems, the present invention proposes a multi-parameter constrained method for characterizing a single channel sand body in a meandering river, the method comprising:

[0005] Carry out fine well-seismic calibration of target river channel sand bodies according to geological stratification;

[0006] Determine the lower threshold value of seismic amplitude energy of target channel sand body based on well logging parameter data;

[0007] Based on the fine well-seismic calibration of the target channel sand body, the maximum amplitude attributes along the layer are extracted to characterize the channel sand body, and the planar distribution morphology of the target channel sand body is characterized by the lower limit threshold of the seismic amplitude energy to determine the boundary of the target channel sand body.

[0008] Furthermore, the logging parameter data includes natural gamma, compressional wave time difference, compensated density logging data and porosity data.

[0009] Furthermore, fine borehole-seismic calibration of target river channel sand bodies based on geological stratification includes:

[0010] Determine the top and bottom seismic response characteristics of the target channel sand body;

[0011] Determine the top and bottom seismic horizons of the target channel sand body;

[0012] Determine the difference in seismic response characteristics between target channel sand bodies and non-reservoir formations.

[0013] Furthermore, the lower threshold value of the seismic amplitude energy of the target channel sand body is determined based on the well logging parameter data, including:

[0014] Determining the correlation characteristics between the logging parameters and the seismic amplitude energy value;

[0015] Determine the boundary values ​​of logging parameters of effective reservoir sand bodies;

[0016] The lower limit threshold value of the seismic amplitude energy of the target channel sand body is determined according to the correlation characteristics and the logging parameter boundary value.

[0017] Furthermore, the lower threshold value of the seismic amplitude energy of the target channel sand body is determined based on the well logging parameter data, including:

[0018] Determine the shale content parameters based on natural gamma ray logging data, and determine the P-wave impedance parameters based on P-wave moveout and compensated density logging data;

[0019] Determine the intersection diagrams of porosity and seismic amplitude energy, P-wave impedance and seismic amplitude energy, and shale content and seismic amplitude energy parameters of the target layer channel sand body and non-reservoir layer;

[0020] The lower limit of seismic amplitude energy of the target channel sand body is determined based on the known lower limit of porosity, upper limit of longitudinal wave impedance and upper limit of mud content of the target layer channel sand body.

[0021] Furthermore, based on the fine well-seismic calibration of the target channel sand body, the maximum amplitude attributes along the layer are extracted to characterize the channel sand body, including:

[0022] The strong amplitude seismic response characteristics are determined based on the difference between the target channel sand body and non-reservoir seismic response characteristics. The maximum amplitude attributes along the layer are extracted based on the strong amplitude seismic response characteristics to characterize the channel sand body.

[0023] The present invention also provides a multi-parameter constrained meandering river single channel sand body characterization system, the system includes a calibration unit, a limit determination unit and a boundary determination unit,

[0024] Calibration unit, used to perform fine well-seismic calibration of target river channel sand bodies according to geological stratification;

[0025] A limit value determination unit is used to determine the lower limit threshold value of the seismic amplitude energy of the target channel sand body based on the well logging parameter data;

[0026] The boundary determination unit is used to extract the maximum amplitude attributes along the layer to characterize the channel sand body based on the fine well-seismic calibration of the target channel sand body, characterize the planar distribution morphology of the target channel sand body with the lower limit threshold value of the seismic amplitude energy, and determine the boundary of the target channel sand body.

[0027] Furthermore, the logging parameter data includes natural gamma, compressional wave time difference, compensated density logging data and porosity data.

[0028] Furthermore, the calibration unit is used to perform fine well-seismic calibration of the target river channel sand body according to geological stratification, including:

[0029] Determine the top and bottom seismic response characteristics of the target channel sand body;

[0030] Determine the top and bottom seismic horizons of the target channel sand body;

[0031] Determine the difference in seismic response characteristics between target channel sand bodies and non-reservoir formations.

[0032] Furthermore, the limit value determination unit includes a related feature module and a first limit value determination module.

[0033] A correlation feature module, used to determine the correlation feature between the logging parameters and the seismic amplitude energy value;

[0034] The first limit value determination module is used to determine the lower limit threshold value of the seismic amplitude energy of the target channel sand body according to the correlation characteristics and the logging parameter boundary value.

[0035] Furthermore, the limit value determination unit includes a parameter determination module, a graph module and a second limit value determination module.

[0036] Parameter determination module, used to determine the shale content parameter based on natural gamma ray logging data, and to determine the P-wave impedance parameter based on P-wave time difference and compensated density logging data;

[0037] The graph module is used to determine the intersection graphs of porosity and seismic amplitude energy, P-wave impedance and seismic amplitude energy, and shale content and seismic amplitude energy parameters of the target layer channel sand body and non-reservoir layer;

[0038] The second limit determination module is used to jointly determine the lower limit threshold value of the seismic amplitude energy of the target channel sand body according to the lower limit value of the porosity, the upper limit value of the longitudinal wave impedance and the upper limit value of the mud content of the target layer channel sand body.

[0039] Furthermore, the boundary determination unit is used to extract the maximum amplitude attributes along the layer to characterize the channel sand body based on the fine well-seismic calibration of the target channel sand body, including:

[0040] The strong amplitude seismic response characteristics are determined based on the difference between the target channel sand body and non-reservoir seismic response characteristics. The maximum amplitude attributes along the layer are extracted based on the strong amplitude seismic response characteristics to characterize the channel sand body.

[0041] The multi-parameter constrained meandering river single channel sand body characterization method and system of the present invention utilizes the relationship between multiple logging parameters and seismic amplitude energy, determines the lower limit of the seismic amplitude energy according to the logging parameter limit value of the channel sand body, and then extracts the maximum amplitude attribute, and uses the lower limit of the amplitude energy as the minimum cutoff value for the maximum amplitude attribute to characterize the channel sand body, thereby achieving the purpose of accurately characterizing the channel sand body. This method can effectively reduce the human uncertainty when using seismic attributes to characterize the channel sand body, making the channel characterization results more reliable and the characterization results more accurate. The present invention can be applied to the characterization of "bright spot" type channel sand bodies, can greatly improve the accuracy of channel sand body characterization, and is of great significance for the accurate identification and characterization of channel sand bodies.

[0042] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0044] Figure 1 A schematic flow chart of a method for characterizing a single channel sand body in a meandering river with multi-parameter constraints according to an embodiment of the present invention is shown;

[0045] Figure 2 A schematic diagram of fine well-seismic calibration of target channel sand bodies in an embodiment of the present invention is shown;

[0046] Figure 3 A schematic diagram of isochronous interface seismic horizon tracking of the target channel sand body envelope in an embodiment of the present invention is shown;

[0047] Figure 4 The intersection diagram of the porosity parameters of the target channel sand body and non-reservoir layer and the seismic amplitude energy value in the embodiment of the present invention is shown;

[0048] Figure 5 It shows the intersection diagram of the target channel sand body and non-reservoir P-wave impedance parameters and seismic amplitude energy values ​​in an embodiment of the present invention;

[0049] Figure 6 It shows the intersection diagram of target channel sand body and non-reservoir mud content parameters and seismic amplitude energy values ​​in an embodiment of the present invention;

[0050] Figure 7 A schematic diagram of accurately depicting the planar distribution and boundaries of a channel sand body by using the lower threshold value of the seismic amplitude energy of the target channel sand body in an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0052] The present invention provides a method for characterizing a single channel sand body of a meandering river with multi-parameter constraints. Figure 1 The figure shows a schematic flow chart of a method for characterizing a single channel sand body of a meandering river with multi-parameter constraints in an embodiment of the present invention. Figure 1 The methods include:

[0053] Carry out fine well-seismic calibration of target river channel sand bodies according to geological stratification;

[0054] Determine the lower threshold value of seismic amplitude energy of target channel sand body based on well logging parameter data;

[0055] Based on the fine well-seismic calibration of the target channel sand body, the maximum amplitude attributes along the layer are extracted to characterize the channel sand body, and the planar distribution morphology of the target channel sand body is characterized by the lower limit threshold of the seismic amplitude energy to determine the boundary of the target channel sand body.

[0056] Specifically, fine well-seismic calibration of target river channel sand bodies based on geological stratification includes:

[0057] Determine the top and bottom seismic response characteristics of the target channel sand body;

[0058] Determine the top and bottom seismic horizons of the target channel sand body;

[0059] Determine the difference in seismic response characteristics between target channel sand bodies and non-reservoir formations.

[0060] In an embodiment of the present invention, fine well-seismic calibration of a target channel sand body based on geological stratification includes: clarifying the top and bottom seismic response characteristics of the target channel sand body, determining the top and bottom seismic horizons of the target channel sand body; clarifying the difference in seismic response characteristics between the target channel sand body and non-reservoir layers;

[0061] In the embodiment of the present invention, the top and bottom isochronous interfaces of the target channel sand body envelope are tracked; the time window for extracting seismic attributes is the top and bottom envelope seismic layers of the target channel sand body, which refers to the isochronous interfaces of the seismic layers including the top and bottom of the target channel sand body; the top and bottom envelope surfaces of the target channel sand body are determined by fine well-seismic calibration. Well-seismic calibration determines the top and bottom seismic reflection characteristics and seismic layers of the target channel sand body, and also clarifies the seismic response characteristics of the target channel sand body that are different from non-reservoir layers, which are "bright spot" characteristics, that is, strong amplitude characteristics;

[0062] In an embodiment of the present invention, based on the fine well-seismic calibration of the target channel sand body, the maximum amplitude attributes along the layer are extracted to characterize the channel sand body, including: determining the strong amplitude seismic response characteristics based on the difference between the seismic response characteristics of the target channel sand body and non-reservoir, that is, based on the "bright spot" seismic response characteristics of the target channel sand body, that is, the strong amplitude seismic response characteristics, extracting the maximum amplitude attributes to characterize the channel sand body.

[0063] In an embodiment of the present invention, determining the lower threshold value of the seismic amplitude energy of the target channel sand body based on the well logging parameter data includes:

[0064] Determining the correlation characteristics between the logging parameters and the seismic amplitude energy value;

[0065] The lower limit threshold value of the seismic amplitude energy of the target channel sand body is determined according to the correlation characteristics and the logging parameter boundary value.

[0066] In an embodiment of the present invention, determining the lower threshold value of the seismic amplitude energy of the target channel sand body based on the well logging parameter data includes:

[0067] Determine the shale content parameters based on natural gamma ray logging data, and determine the P-wave impedance parameters based on P-wave moveout and compensated density logging data;

[0068] Determine the intersection diagrams of porosity and seismic amplitude energy, P-wave impedance and seismic amplitude energy, and shale content and seismic amplitude energy parameters of the target layer channel sand body and non-reservoir layer;

[0069] The lower limit of seismic amplitude energy of the target channel sand body is determined based on the known lower limit of porosity, upper limit of longitudinal wave impedance and upper limit of mud content of the target layer channel sand body.

[0070] An intersection diagram of porosity and seismic amplitude energy, P-wave impedance and seismic amplitude energy, and shale content and seismic amplitude energy parameters is generated for the target channel sand body and non-reservoir layers. In the embodiment of the present invention, the logging parameter data includes natural gamma, acoustic transit time, compensated density logging data, and porosity (core analysis porosity or logging interpretation porosity). In actual application, the selection of logging parameters and types is for illustrative purposes only and does not limit the number and type of logging parameters. Users can make specific selections based on actual data and analyze their correlation characteristics. The seismic amplitude energy lower limit threshold value of the target channel sand body is determined based on the porosity lower limit value, P-wave impedance upper limit value, and shale content upper limit value of the target reservoir sand body. In the embodiment of the present invention, by studying the correlation (positive correlation / negative correlation) between logging parameters and seismic amplitude energy values, the seismic amplitude energy lower limit threshold value of the effective reservoir sand body is determined based on the amplitude energy boundary that distinguishes the channel sand body from the non-reservoir layer on the intersection diagram and the boundary values ​​of each logging parameter.

[0071] Specifically, in the embodiment of the present invention, the process of producing the intersection chart of multi-parameter constrained seismic amplitude energy values ​​includes:

[0072] The relationship between various logging parameters and seismic amplitude energy values ​​of the target river sand bodies and non-reservoir layers in the research area is established, and intersection diagrams of porosity and seismic amplitude energy value, longitudinal wave impedance and seismic amplitude energy value, and mud content and seismic amplitude energy value are prepared respectively to form the multi-parameter constrained seismic amplitude energy value intersection diagram.

[0073] The lower seismic amplitude energy threshold for the target channel sand body is determined by combining the bounds of multiple logging parameters, including the lower limit of porosity, the upper limit of compressional wave impedance, and the upper limit of shale content in the target reservoir sand body. The lower seismic amplitude energy threshold for the target channel sand body is determined by combining the correlation characteristics between these logging parameters and the seismic amplitude energy values, along with the bounds of the logging parameters of the effective reservoir sand body.

[0074] In the embodiment of the present invention, the porosity parameter is the laboratory measured porosity or the porosity interpreted by well logging of the target layer, target channel sand body and non-reservoir layer.

[0075] The calculation formula of longitudinal wave impedance parameters is:

[0076] Z p =ρ·V p

[0077] Among them, Z p is the longitudinal wave impedance, unit (g·cm -3 )·(m·s -1 ); ρ is the compensation density, unit is g·cm -3 ; V p is the longitudinal wave velocity, in m·s-1 .

[0078] The calculation formula for longitudinal wave velocity is:

[0079]

[0080] Among them, △t c is the longitudinal wave time difference, unit is μs·m -1 .

[0081] The calculation formula for mud content is:

[0082]

[0083]

[0084] Among them, SH is the shale index, which has no unit;

[0085] GR is the natural gamma logging value of the target channel sand body or non-reservoir, in API units;

[0086] GRmin is the natural gamma logging value of pure sandstone, in API units;

[0087] GRmax is the natural gamma logging value of pure mudstone, in API units;

[0088] V sh is the mud content, unit: %;

[0089] GCUR is an empirical coefficient related to the stratum. The GCUR of the new stratum (Tertiary stratum) is 3.7, and the GUCR of the old stratum is 2.0.

[0090] In the embodiment of the present invention, natural gamma, P-wave moveout and compensated density are obtained by conventional well logging.

[0091] According to the "bright spot" seismic response characteristics of the target channel sand body, the maximum amplitude attributes along the layer are extracted. The lower limit threshold value of the seismic amplitude energy of the target channel sand body is used as the cutoff value to characterize the planar distribution morphology of the target channel sand body and determine the boundary of the target channel sand body.

[0092] This method combines well and seismic data, leveraging the relationship between multiple well logging parameters and seismic amplitude energy for the target channel sand body. Based on the threshold values ​​(upper, lower, or interval values) of each logging parameter in the effective reservoir, the lower threshold value for the amplitude energy of the target channel sand body is comprehensively determined. Using this lower threshold value as a cutoff, the planar distribution of the target channel sand body is characterized using the maximum amplitude attribute to determine its boundary. Multi-parameter constrained seismic data can eliminate uncertainty in identifying channel sand bodies using seismic data, resulting in more accurate identification results.

[0093] In the embodiment of the present invention, a method for characterizing a single channel sand body of a meandering river with multi-parameter constraints is further described in detail with reference to the accompanying drawings:

[0094] Obtain natural gamma ray, P-wave time difference, compensated density logging data, porosity (core analysis porosity or logging interpretation porosity), geological stratification and post-stack seismic data of the target layer drilled in the study area;

[0095] Based on geological stratification, fine well-seismic calibration of target river channel sand bodies is carried out. Figure 2 The figure shows a schematic diagram of fine well-seismic calibration of the target channel sand body in an embodiment of the present invention, including clarifying the top and bottom seismic response characteristics of the target channel sand body and determining the top and bottom seismic horizons of the target channel sand body; clarifying the difference in seismic response characteristics between the target channel sand body and non-reservoir layers. In the embodiment of the present invention, the box-shaped low value of the GR curve is the channel sand body development section, and the rest is mudstone or sandy mudstone non-reservoir layers. Figure 2 The seismic response characteristics corresponding to the medium and low GR are "bright spots", that is, strong troughs and strong peaks, while other non-reservoir layers have relatively weak amplitude characteristics. Figure 2 In the embodiment, aa1-top and aa1-bot are used to represent the top and bottom geological layers of the target channel sand body, respectively, and acoustic time difference (AC), wave impedance (IMP), and natural gamma (GR) are established to clarify the logging response characteristics of the target channel sand body. Synthetic seismic records (syn), seismic data (seidmic), and time / depth (Time / Depth) are used to describe the seismic response characteristics of the target channel sand body. After determining the difference, in the embodiment of the present invention, the top and bottom isochronous interface seismic horizons of the target channel sand body envelope are also tracked. Figure 3 The diagram shows the isochronous interface seismic horizon tracking diagram of the target channel sand body envelope in an embodiment of the present invention. Figure 3 In the process, the top and bottom isochronous interface seismic horizons of the target channel sand body are tracked by calibrating the known well (J1) to determine the spatial position of the target channel sand body on the seismic data.

[0096] Calculation of shale content (V) using natural gamma log data sh ) parameters, and the P-wave impedance (Z p ) parameters. In the embodiment of the present invention, the calculation of the mud content and the longitudinal wave impedance parameters has been described above and will not be repeated here.

[0097] Produce intersection diagrams of the porosity and seismic amplitude energy value, the P-wave impedance and seismic amplitude energy value, and the shale content and seismic amplitude energy value of the target layer channel sand body and non-reservoir layer (this embodiment does not limit the number and types of logging parameters, and users can make specific selections based on actual data); Figure 4The intersection diagram of the porosity parameters of the target channel sand body and non-reservoir layer and the seismic amplitude energy value in the embodiment of the present invention is shown. Figure 4 In the figure, the horizontal axis represents porosity POR / %, the vertical axis represents seismic amplitude energy value, and in the intersection diagram, the upper right corner represents channel sand body parameters, and the lower left corner represents non-energy storage parameters. The lower limit of the porosity of the effective reservoir sand body in the target layer is POR>6%. The selection of the number, type and limit values ​​of the logging parameters in the embodiments of the present invention are all illustrative. Without departing from the technical concept of the present invention, the change of the number, type and limit values ​​of the logging parameters is also within the protection scope of the present invention.

[0098] Figure 5 The intersection diagram of the target channel sand body and non-reservoir P-wave impedance parameters and seismic amplitude energy values ​​in the embodiment of the present invention is shown. Figure 5 In the figure, the horizontal axis represents the longitudinal wave impedance parameter Z p (g·cm -3 )·(m·s -1 ), the vertical axis represents the seismic amplitude energy value. In the intersection diagram, the upper left corner represents the channel sand body parameters, and the lower right corner represents the non-energy storage parameters. In the embodiment of the present invention, the upper limit of the longitudinal wave impedance of the effective reservoir sand body in the target layer is 11000 (g·cm -3 )·(m·s -1 ), namely Z p <11000(g·cm -3 )·(m·s -1 ).

[0099] Figure 6 The intersection diagram of the target channel sand body and non-reservoir mud content parameters and seismic amplitude energy values ​​in the embodiment of the present invention is shown. Figure 6 In the figure, the horizontal axis represents the mud content V sh / %, the vertical axis represents the seismic amplitude energy value. In the intersection diagram, the upper left corner represents the channel sand body parameters, and the lower right corner represents the non-energy storage parameters. In the embodiment of the present invention, the upper limit of the mud content of the effective reservoir sand body in the target layer is 40%, that is, V sh <40%.

[0100] In the embodiment of the present invention, the correlation characteristics are analyzed, and according to the lower limit value of the porosity of the effective reservoir sand body of the target layer (POR>6%), the upper limit value of the longitudinal wave impedance (Z p <11000(g·cm -3 )·(m·s -1 )) and upper limit of mud content (Example V sh<40%) to jointly determine the lower limit threshold value of the seismic amplitude energy of the target channel sand body. In the embodiment of the present invention, the seismic amplitude energy threshold value for distinguishing the channel sand body from the non-reservoir layer is visually read on the intersection diagram of the logging parameters and the seismic amplitude energy value, and the lower limit threshold value of the seismic amplitude energy is determined to be 3000.

[0101] According to the "bright spot" seismic response characteristics of the target channel sand body, the maximum wave peak amplitude attribute along the layer is extracted, and the lower limit threshold value of the seismic amplitude energy of the target channel sand body (3000) is used as the cutoff value to characterize the plane distribution morphology of the target channel sand body and determine the boundary of the target channel sand body. Figure 7 The figure shows a schematic diagram of accurately depicting the planar distribution and boundary of the channel sand body by using the lower threshold value of the seismic amplitude energy of the target channel sand body in an embodiment of the present invention. Figure 7 In the figure, the planar distribution morphology of the target channel sand body is depicted by the lower limit threshold value of the seismic amplitude energy. The maximum upper limit value of the seismic amplitude energy in the figure is 8000, but this value is only the maximum value for determining the boundary of the target channel sand body in the embodiment of the present invention. In actual application, the maximum limit value of the boundary of the target channel sand body is not specifically described.

[0102] In an embodiment of the present invention, a multi-parameter constrained meandering river single channel sand body characterization system is also provided, the system comprising a calibration unit, a limit determination unit and a boundary determination unit.

[0103] Calibration unit, used to perform fine well-seismic calibration of target river channel sand bodies according to geological stratification;

[0104] A limit value determination unit is used to determine the lower limit threshold value of the seismic amplitude energy of the target channel sand body based on the well logging parameter data;

[0105] The boundary determination unit is used to extract the maximum amplitude attributes along the layer to characterize the channel sand body based on the fine well-seismic calibration of the target channel sand body, characterize the planar distribution morphology of the target channel sand body with the lower limit threshold value of the seismic amplitude energy, and determine the boundary of the target channel sand body.

[0106] Specifically, the limit value determination unit includes a related feature module and a first limit value determination module.

[0107] A correlation feature module, used to determine the correlation feature between the logging parameters and the seismic amplitude energy value;

[0108] The first limit value determination module is used to determine the lower limit threshold value of the seismic amplitude energy of the target channel sand body according to the correlation characteristics and the logging parameter boundary value.

[0109] Specifically, the limit value determination unit includes a parameter determination module, a graph module and a second limit value determination module.

[0110] Parameter determination module, used to determine the shale content parameter based on natural gamma ray logging data, and to determine the P-wave impedance parameter based on P-wave time difference and compensated density logging data;

[0111] The graph module is used to determine the intersection graphs of porosity and seismic amplitude energy, P-wave impedance and seismic amplitude energy, and shale content and seismic amplitude energy parameters of the target layer channel sand body and non-reservoir layer;

[0112] The second limit determination module is used to jointly determine the lower limit threshold value of the seismic amplitude energy of the target channel sand body according to the lower limit value of the porosity, the upper limit value of the longitudinal wave impedance and the upper limit value of the mud content of the target layer channel sand body.

[0113] Specifically, the boundary determination unit is used to extract the maximum amplitude attributes along the layer to characterize the channel sand body based on the fine well-seismic calibration of the target channel sand body, including:

[0114] The strong amplitude seismic response characteristics are determined based on the difference between the target channel sand body and non-reservoir seismic response characteristics. The maximum amplitude attributes along the layer are extracted based on the strong amplitude seismic response characteristics to characterize the channel sand body.

[0115] The multi-parameter constrained meandering river single channel sand body characterization method and system of the present invention utilizes the relationship between multiple logging parameters and seismic amplitude energy, determines the lower limit of the seismic amplitude energy according to the logging parameter limit value of the channel sand body, and then extracts the maximum amplitude attribute, and uses the lower limit of the amplitude energy as the minimum cutoff value for the maximum amplitude attribute to characterize the channel sand body, thereby achieving the purpose of accurately characterizing the channel sand body. This method can effectively reduce the human uncertainty when using seismic attributes to characterize the channel sand body, making the channel characterization results more reliable and the characterization results more accurate. The present invention can be applied to the characterization of "bright spot" type channel sand bodies, can greatly improve the accuracy of channel sand body characterization, and is of great significance for the accurate identification and characterization of channel sand bodies.

[0116] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-parameter constrained method for characterizing a single channel sand body in a meandering river, characterized by: The method comprises: Carry out fine well-seismic calibration of target river channel sand bodies according to geological stratification; Determine the lower threshold value of seismic amplitude energy of target channel sand body based on well logging parameter data; Based on the fine well-seismic calibration of the target channel sand body, the maximum amplitude attributes along the layer are extracted to characterize the channel sand body, and the planar distribution morphology of the target channel sand body is characterized by the lower limit threshold of the seismic amplitude energy to determine the boundary of the target channel sand body.

2. The multi-parameter constrained meandering river single channel sand body characterization method according to claim 1 is characterized in that: The logging parameter data include natural gamma, compressional wave time difference, compensated density logging data and porosity data.

3. The multi-parameter constrained meandering river single channel sand body characterization method according to claim 1 or 2, characterized in that: Fine borehole seismic calibration of target river channel sand bodies based on geological stratification includes: Determine the top and bottom seismic response characteristics of the target channel sand body; Determine the top and bottom seismic horizons of the target channel sand body; Determine the difference in seismic response characteristics between target channel sand bodies and non-reservoir formations.

4. The multi-parameter constrained meandering river single channel sand body characterization method according to claim 1 is characterized in that: The lower threshold value of seismic amplitude energy of target channel sand body determined based on well logging parameter data includes: Determining the correlation characteristics between the logging parameters and the seismic amplitude energy value; Determine the boundary values ​​of logging parameters of effective reservoir sand bodies; The lower limit threshold value of the seismic amplitude energy of the target channel sand body is determined according to the correlation characteristics and the logging parameter boundary value.

5. The multi-parameter constrained meandering river single channel sand body characterization method according to claim 2, characterized in that: The lower threshold value of seismic amplitude energy of target channel sand body determined based on well logging parameter data includes: Determine the shale content parameters based on natural gamma ray logging data, and determine the P-wave impedance parameters based on P-wave moveout and compensated density logging data; Determine the intersection diagrams of porosity and seismic amplitude energy, P-wave impedance and seismic amplitude energy, and shale content and seismic amplitude energy parameters of the target layer channel sand body and non-reservoir layer; The lower limit of seismic amplitude energy of the target channel sand body is determined based on the known lower limit of porosity, upper limit of longitudinal wave impedance and upper limit of mud content of the target layer channel sand body.

6. The multi-parameter constrained meandering river single channel sand body characterization method according to claim 3, characterized in that: Based on the fine well-seismic calibration of the target channel sand body, the maximum amplitude attributes along the layer are extracted to characterize the channel sand body, including: The strong amplitude seismic response characteristics are determined based on the difference between the target channel sand body and non-reservoir seismic response characteristics. The maximum amplitude attributes along the layer are extracted based on the strong amplitude seismic response characteristics to characterize the channel sand body.

7. A multi-parameter constrained meandering river single channel sand body characterization system, characterized by: The system includes a calibration unit, a limit determination unit and a boundary determination unit, Calibration unit, used to perform fine well-seismic calibration of target river channel sand bodies according to geological stratification; A limit value determination unit is used to determine the lower limit threshold value of the seismic amplitude energy of the target channel sand body based on the well logging parameter data; The boundary determination unit is used to extract the maximum amplitude attributes along the layer to characterize the channel sand body based on the fine well-seismic calibration of the target channel sand body, characterize the planar distribution morphology of the target channel sand body with the lower limit threshold value of the seismic amplitude energy, and determine the boundary of the target channel sand body.

8. The multi-parameter constrained meandering river single channel sand body characterization system according to claim 7, characterized in that: The logging parameter data include natural gamma, compressional wave time difference, compensated density logging data and porosity data.

9. The multi-parameter constrained meandering river single channel sand body characterization system according to claim 7 or 8, characterized in that: The calibration unit is used to perform fine well-seismic calibration of the target river channel sand body according to geological stratification, including: Determine the top and bottom seismic response characteristics of the target channel sand body; Determine the top and bottom seismic horizons of the target channel sand body; Determine the difference in seismic response characteristics between target channel sand bodies and non-reservoir formations.

10. The multi-parameter constrained meandering river single channel sand body characterization system according to claim 7, characterized in that: The limit value determination unit includes a related feature module and a first limit value determination module, A correlation feature module, used to determine the correlation feature between the logging parameters and the seismic amplitude energy value; The first limit value determination module is used to determine the lower limit threshold value of the seismic amplitude energy of the target channel sand body according to the correlation characteristics and the logging parameter boundary value.

11. The multi-parameter constrained meandering river single channel sand body characterization system according to claim 8, characterized in that: The limit value determination unit includes a parameter determination module, a graph module and a second limit value determination module. Parameter determination module, used to determine the shale content parameter based on natural gamma ray logging data, and to determine the P-wave impedance parameter based on P-wave time difference and compensated density logging data; The graph module is used to determine the intersection graphs of porosity and seismic amplitude energy, P-wave impedance and seismic amplitude energy, and shale content and seismic amplitude energy parameters of the target layer channel sand body and non-reservoir layer; The second limit determination module is used to jointly determine the lower limit threshold value of the seismic amplitude energy of the target channel sand body according to the lower limit value of the porosity, the upper limit value of the longitudinal wave impedance and the upper limit value of the mud content of the target layer channel sand body.

12. The multi-parameter constrained meandering river single channel sand body characterization system according to claim 9, characterized in that: The boundary determination unit is used to extract the maximum amplitude attributes along the layer to characterize the channel sand body based on the fine well-seismic calibration of the target channel sand body, including: The strong amplitude seismic response characteristics are determined based on the difference between the target channel sand body and non-reservoir seismic response characteristics. The maximum amplitude attributes along the layer are extracted based on the strong amplitude seismic response characteristics to characterize the channel sand body.

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