CN106707336B - Method for distinguishing upper and lower fault trays in oilfield development area - Google Patents

Abstract

A method for distinguishing fault upper and lower plates for an oil field development area is provided, and the method comprises the following steps: acquiring well drilling layered data; in the case where the fault is a reverse fault: creating an upper disk data file and a lower disk data file based on the drilling hierarchical data, wherein the upper disk data file comprises hierarchical data which only encounters the stratum once, and hierarchical data which has a shallower depth in the hierarchical data which encounters the stratum twice; the lower data file comprises hierarchical data which only encounters the stratum once and hierarchical data which has a deeper depth in the hierarchical data which encounters the stratum twice; projecting the layered data in the hanging wall data file in a seismic data interpretation system, and identifying the breakpoint position corresponding to the hanging wall of the fault; projecting the layered data in the footwall data file in a seismic data interpretation system, and identifying the breakpoint position corresponding to the footwall of the fault; and distinguishing an upper plate and a lower plate of the fault without the well region according to the seismic reflection characteristics of the breakpoint identified in the well region.

Description

Method for distinguishing upper and lower fault trays in oilfield development area

Technical Field

The invention relates to the field of seismic data interpretation, in particular to a method for distinguishing upper and lower fault footings in an oil field development area.

Background

The method is characterized in that the upper wall and the lower wall of the fault are very important links of a real structure, data used for distinguishing fault breakpoints by a seismic data interpreter mainly come from a seismic data body and well drilling hierarchical data, the well drilling hierarchical data are relatively simple ASCII data and can not visually distinguish the fault breakpoints, and in the prior art, the upper wall and the lower wall of the geological fault are identified by more seismic data, and the breakpoints are accurately depicted based on the data with higher seismic resolution. The existing technology relies on seismic attributes such as a coherence technology, an ant body technology, a variance body technology, an obliquity analysis technology, three-dimensional visualization and other technologies to assist fault identification, but a complex fault zone is often a seismic aberration area, so that uncertainty is brought to seismic attribute extraction, and fault identification accuracy is restricted. Particularly, the upper and lower plates of the reverse fault are difficult to distinguish due to the repeated phenomenon of the stratum and the poor seismic imaging effect.

Disclosure of Invention

One of the purposes of the disclosure is to provide a method for distinguishing the upper and lower walls of a fault in an oil field development area, the method applies well drilling layered data in a well ASCII format to the breakpoints of the upper and lower walls of the fault, simultaneously, no well area is combined with seismic data, the seismic reflection characteristic of the well area seismic breakpoints is learned, well seismic combination is achieved, and the fault is distinguished.

According to one aspect of the invention, a method for distinguishing fault footage and fault footage in an oilfield development area is provided, the method comprising: obtaining well drilling stratification data, the well drilling stratification data representing stratification data of a well drilling tool in a well zone encountering a formation, wherein the formation is cut by a fault; in the case where the fault is a reverse fault, the upper and lower trays of the fault are distinguished according to the following steps: creating an upper disk data file and a lower disk data file based on the drilling hierarchical data, wherein the upper disk data file comprises hierarchical data which only encounters the stratum once, and hierarchical data which has a shallower depth in the hierarchical data which encounters the stratum twice; the lower data file comprises hierarchical data which only encounters the stratum once and hierarchical data which has a deeper depth in the hierarchical data which encounters the stratum twice; projecting the layered data in the hanging wall data file in a seismic data interpretation system, representing different depths of the layered data by using different identifiers, and judging the position of the depth mutation of the layered data according to the identifiers to be used as the breakpoint position corresponding to the hanging wall of the fault; projecting the layered data in the footwall data file in a seismic data interpretation system, representing different depths of the layered data by using different identifiers, and judging the position of the depth of the layered data with sudden change according to the identifiers to be used as the breakpoint position corresponding to the footwall of the fault; and searching similar reflection in the seismic data of the fault of the non-well region according to the seismic reflection characteristics of the breakpoint identified in the well region so as to determine the breakpoint of the fault of the non-well region, thereby distinguishing the upper tray and the lower tray of the fault of the non-well region.

The method is independent of complex seismic data extraction, well-zone breakpoint position range can be accurately judged by drilling the position of a stratum met by a well, upper and lower plates are visually and accurately identified by well-drilling layered projection, no well zone learns well-zone seismic reflection characteristics to distinguish breakpoints, well seismic is combined, compared with the prior art, the method greatly reduces judgment complexity while ensuring judgment accuracy, and is particularly suitable for areas with poor complex fault zone seismic imaging, so that oil field development service can be better realized

Drawings

The above and other objects, features and advantages of the present disclosure will become more apparent by describing in greater detail exemplary embodiments thereof with reference to the attached drawings, in which like reference numerals generally represent like parts throughout.

FIG. 1 shows a flow diagram of a method of distinguishing between upper and lower walls of a fault according to one embodiment of the invention.

Fig. 2 shows a schematic diagram of the principle of an embodiment of the invention for a reverse fault.

FIG. 3 illustrates an example of a plan view of a footwall breakpoint of a y-layer of an X-ray of a certain oil field development area distinguished using a method of an embodiment of the present invention.

Detailed Description

Preferred embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While the preferred embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

FIG. 1 illustrates a method for discriminating between upper and lower fault trays in an oilfield development area, according to one embodiment of the invention, the method comprising:

step 101, obtaining well drilling layered data, wherein the well drilling layered data represent layered data of a well drilling tool in a well region and meeting a stratum, and the stratum is cut by a fault;

step 102, in the case that the fault is a reverse fault, distinguishing an upper plate and a lower plate of the fault according to the following steps:

step 1021, an upper disk data file and a lower disk data file are created based on the drilling hierarchical data, wherein the upper disk data file comprises hierarchical data which only encounters the stratum once, and hierarchical data which has a shallower depth in the hierarchical data which encounters the stratum twice; the lower data file comprises hierarchical data which only encounters the stratum once and hierarchical data which has a deeper depth in the hierarchical data which encounters the stratum twice;

step 1022, projecting the layered data in the hanging wall data file in a seismic data interpretation system, representing different depths of the layered data by using different identifiers, and judging the position of the depth mutation of the layered data according to the identifiers to be used as the breakpoint position corresponding to the hanging wall of the fault;

step 1023, projecting the layered data in the footwall data file in a seismic data interpretation system, representing different depths of the layered data by using different identifiers, and judging the position of abrupt change of the depth of the layered data according to the identifiers to serve as the position of a breakpoint corresponding to the footwall of the fault; and

andstep 1024, searching similar reflection in the seismic data of the fault of the non-well region according to the seismic reflection characteristics of the breakpoint identified in the well region to determine the breakpoint of the fault of the non-well region, so as to distinguish the upper tray and the lower tray of the fault of the non-well region.

The method is independent of complex seismic data extraction, well-zone breakpoint position range can be accurately judged by drilling the position of a stratum met by a well, upper and lower plates are visually and accurately identified by well-drilling layered projection, no well zone learns well-zone seismic reflection characteristics to distinguish breakpoints, well seismic is combined, compared with the prior art, the method greatly reduces judgment complexity while ensuring judgment accuracy, and is particularly suitable for areas with poor complex fault zone seismic imaging, so that oil field development service can be better realized

Fig. 2 shows a schematic diagram of the principle of an embodiment of the invention for a reverse fault. Where K1 denotes the ground, D denotes the lower wall of the fault, and U denotes the upper wall of the fault. The principle of the scheme is described by taking three drilling wells, namely a drilling well, b drilling well and c drilling well as a representative drilling well in a well zone, wherein the drilling wells b and c drilling well represent drilling wells which only meet a stratum K1 once, the drilling well b is divided into b1, and the drilling well c is divided into c 1; the a-well represents a well drilled twice to the formation K1, where the shallower depth in the a-well interval is a1 and the deeper depth is a 2.

It will be understood by those skilled in the art that three wells are drawn for illustrative purposes only, and that in practice the number of wells of the same type as a, b, c in the target area is not limited to the one shown in the figures, but rather may reach hundreds or even thousands or more per type of well, depending on the needs of the actual project.

According to the structural characteristics of the reverse fault shown in fig. 2, near the break point a corresponding to the upper disc, the depth of each of the layers a1 and b1 is necessarily similar since they both correspond to the upper disc, while the depth of c1 corresponds to the lower disc, which is greatly different from that of a1 and b1, and the break point a is necessarily located between c1 and a 1. Based on the principle, the c1, a1 and b1 hierarchical data can be put into the upper disk data file, and the position or position range of the depth mutation can be found by projecting to the interpretation system, namely the position or position range of the breakpoint a can be considered.

Similarly, near break point B corresponding to the lower disk, the data of hierarchy c1, a2 are necessarily similar, while the depth difference from B1 is larger, and break point B is necessarily located between a2 and B1. Based on the principle, the c1, a2 and B1 data can be put into a lower disk data file, and the position or position range of the abrupt depth change can be found by projecting the data to an interpretation system, namely the position or position range of the breakpoint B can be considered.

And the upper disc and the lower disc of the fault can be distinguished based on the positions or position ranges of the breakpoint A and the breakpoint B.

In one example, the method further comprises: when the fault is a normal fault, an upper wall (ascending wall) and a lower wall (descending wall) of the fault can be determined from the depth difference of the hierarchical data. The normal fault is simpler than the reverse fault, and the depths of the hierarchical data of the ascending disk and the descending disk are significantly different, so that the ascending disk and the descending disk of the fault can be determined only according to the depth difference of the hierarchical data.

Whether a fault is a normal fault or a reverse fault can be determined in any manner by one skilled in the art based on his experience. In one example, whether the fault is a reverse fault or a normal fault may be determined by: and judging whether the layered data of drilling the stratum twice exists or not according to the drilling layered data, if so, considering the fault as a reverse fault, and otherwise, considering the fault as a normal fault. The principle of this approach is based on the structural features of both normal and reverse faults, as shown in fig. 2, if the fault is a reverse fault, there will be a well drilled twice into the formation, such as well a, while the normal fault will not. This type of determination is typically made at a sufficient depth of the borehole and is typically made in conjunction with geological analysis.

In one example, it may be determined whether there is stratified data that is drilled twice into the formation by: if the layered data of a certain well comprises two sets of layered data with the depth difference exceeding the threshold value, the layered data of the well is considered to be the layered data which is drilled with the stratum twice. Wherein, the deeper one of the two sets of hierarchical data can be stored in the lower disk data file, and the shallower one can be stored in the upper disk data file. The principle of this judgment method can be seen from fig. 2, that is, the layered data of the drilling well a meeting two strata contains two sets of layered data with great depth difference, namely the data of the a1 layer and the data of the a2 layer.

The seismic data interpretation system in the present embodiment may be any seismic data interpretation system that can be selected by those skilled in the art according to actual needs. According to the difference of the seismic data interpretation system and the requirement of the skilled person, any mark can be used to represent the depth of the layered data, for example, the mark can be one or more of color, symbol or gray scale, and by this intuitive way, the accurate position of the breakpoint can be distinguished conveniently and accurately.

In one example, a fault seismic breakpoint characteristic of a well region can be obtained according to a breakpoint position of the well region; this process may be accomplished by projecting the breakpoint onto the seismic profile of the well area. Based on the fault earthquake breakpoint characteristics of the well-containing area, the fault earthquake breakpoint characteristics of the well-containing area can be learned in the earthquake data of the well-free area to identify breakpoints of the well-free area, so that an upper plate and a lower plate of faults of the well-free area are distinguished, and the purpose of accurately identifying the upper plate and the lower plate of the faults by combining well earthquake is achieved. The fault earthquake breakpoint characteristics can be wave group characteristics, reflection phenomena and the like.

Effect schematic of application example

To facilitate understanding of the solution of the embodiment of the present invention and its effect, an effect illustration of a specific application example is given below. It will be understood by those skilled in the art that this example is merely for the purpose of facilitating an understanding of the present invention and that any specific details thereof are not intended to limit the invention in any way.

FIG. 3 illustrates an example of a plan view of a footwall breakpoint of layer K1 for a certain oil field development area X-ray fault distinguished using a method of an embodiment of the present invention.

The X-ray fault of the region is a reverse fault, seismic imaging near the fault is very poor, a lot of wells are drilled, but the accurate positions of the upper and lower walls are difficult to identify, the upper and lower walls can be accurately distinguished from each other according to the gray level difference by using the method of the embodiment, and the method is more accurate than the original fault depiction.

Each point on the graph is a projection of the well drilling tool on a plane encountering K1 layered data, wherein different depths of the layered data are represented by gray scale, and compared with an original fault, the fracture surface has the characteristic of being unsmooth, but is more real and accurate than the original fracture point.

The present disclosure may be systems, methods, and/or computer program products. The computer program product may include a computer-readable storage medium having computer-readable program instructions embodied thereon for causing a processor to implement various aspects of the present disclosure.

The computer readable storage medium may be a tangible device that can hold and store the instructions for use by the instruction execution device. The computer readable storage medium may be, for example, but not limited to, an electronic memory device, a magnetic memory device, an optical memory device, an electromagnetic memory device, a semiconductor memory device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer readable storage medium would include the following: a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a Static Random Access Memory (SRAM), a portable compact disc read-only memory (CD-ROM), a Digital Versatile Disc (DVD), a memory stick, a floppy disk, a mechanical coding device, such as punch cards or in-groove projection structures having instructions stored thereon, and any suitable combination of the foregoing. Computer-readable storage media as used herein is not to be construed as transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission medium (e.g., optical pulses through a fiber optic cable), or electrical signals transmitted through electrical wires.

The computer-readable program instructions described herein may be downloaded from a computer-readable storage medium to a respective computing/processing device, or to an external computer or external storage device via a network, such as the internet, a local area network, a wide area network, and/or a wireless network. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers and/or edge servers. The network adapter card or network interface in each computing/processing device receives computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in a computer-readable storage medium in the respective computing/processing device.

The computer program instructions for carrying out operations of the present disclosure may be assembler instructions, Instruction Set Architecture (ISA) instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source or object code written in any combination of one or more programming languages, including an object oriented programming language such as Smalltalk, C + + or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet service provider). In some embodiments, the electronic circuitry that can execute the computer-readable program instructions implements aspects of the present disclosure by utilizing the state information of the computer-readable program instructions to personalize the electronic circuitry, such as a programmable logic circuit, a Field Programmable Gate Array (FPGA), or a Programmable Logic Array (PLA).

Various aspects of the present disclosure are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the disclosure. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer-readable program instructions.

These computer-readable program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. These computer-readable program instructions may also be stored in a computer-readable storage medium that can direct a computer, programmable data processing apparatus, and/or other devices to function in a particular manner, such that the computer-readable medium storing the instructions comprises an article of manufacture including instructions which implement the function/act specified in the flowchart and/or block diagram block or blocks.

The computer readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer, other programmable apparatus or other devices implement the functions/acts specified in the flowchart and/or block diagram block or blocks.

The flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of instructions, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

Having described embodiments of the present disclosure, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terms used herein were chosen in order to best explain the principles of the embodiments, the practical application, or technical improvements to the techniques in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

Claims (2)

1. A method for discriminating between upper and lower walls of a fault in an oilfield development area, the method comprising:

obtaining well drilling stratification data, the well drilling stratification data representing stratification data of a well drilling tool in a well zone encountering a formation, wherein the formation is cut by a fault;

in the case where the fault is a reverse fault, the upper and lower trays of the fault are distinguished according to the following steps:

creating an upper disk data file and a lower disk data file based on the drilling hierarchical data, wherein the upper disk data file comprises hierarchical data which only encounters the stratum once, and hierarchical data which has a shallower depth in the hierarchical data which encounters the stratum twice; the lower data file comprises hierarchical data which only encounters the stratum once and hierarchical data which has a deeper depth in the hierarchical data which encounters the stratum twice;

projecting the layered data in the hanging wall data file in a seismic data interpretation system, representing different depths of the layered data by using different identifiers, and judging the position of the depth mutation of the layered data according to the identifiers to be used as the breakpoint position corresponding to the hanging wall of the fault;

projecting the layered data in the footwall data file in a seismic data interpretation system, representing different depths of the layered data by using different identifiers, and judging the position of the depth of the layered data with sudden change according to the identifiers to be used as the breakpoint position corresponding to the footwall of the fault; and

according to the seismic reflection characteristics of the breakpoint identified in the well region, searching similar reflection in the seismic data of the fault of the non-well region to determine the breakpoint of the fault of the non-well region, and accordingly distinguishing an upper wall and a lower wall of the fault of the non-well region;

the method further comprises: determining that the fault is a reverse fault by:

judging whether layered data which drills into the stratum twice exists or not according to the drilling layered data, and if so, considering the fault as a reverse fault;

wherein, according to the well drilling layering data, judging whether the layering data which is drilled twice in the stratum comprises the following steps:

if the layered data of a certain well comprises two sets of layered data with the depth difference exceeding a threshold value, the layered data of the well is considered to be the layered data which is drilled twice in the stratum;

wherein, the deeper one of the two sets of hierarchical data is stored in the lower disk data file, and the shallower one is stored in the upper disk data file.

2. The method for distinguishing between upper and lower fault trays for an oilfield development area of claim 1, wherein the identification is one or more of a color, a symbol, or a grayscale.

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