CN109212593B - Longitudinal and transverse wave combined positioning method based on multiple perforation double differences - Google Patents

Longitudinal and transverse wave combined positioning method based on multiple perforation double differences Download PDF

Info

Publication number
CN109212593B
CN109212593B CN201710528514.8A CN201710528514A CN109212593B CN 109212593 B CN109212593 B CN 109212593B CN 201710528514 A CN201710528514 A CN 201710528514A CN 109212593 B CN109212593 B CN 109212593B
Authority
CN
China
Prior art keywords
event
longitudinal
travel time
perforation
positioning
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201710528514.8A
Other languages
Chinese (zh)
Other versions
CN109212593A (en
Inventor
余波
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China Petroleum and Chemical Corp
Sinopec Geophysical Research Institute
Original Assignee
China Petroleum and Chemical Corp
Sinopec Geophysical Research Institute
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by China Petroleum and Chemical Corp, Sinopec Geophysical Research Institute filed Critical China Petroleum and Chemical Corp
Priority to CN201710528514.8A priority Critical patent/CN109212593B/en
Publication of CN109212593A publication Critical patent/CN109212593A/en
Application granted granted Critical
Publication of CN109212593B publication Critical patent/CN109212593B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
    • G01V1/28—Processing seismic data, e.g. analysis, for interpretation, for correction
    • G01V1/282—Application of seismic models, synthetic seismograms
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
    • G01V1/28—Processing seismic data, e.g. analysis, for interpretation, for correction
    • G01V1/36—Effecting static or dynamic corrections on records, e.g. correcting spread; Correlating seismic signals; Eliminating effects of unwanted energy

Abstract

A longitudinal and transverse wave combined positioning method based on multiple perforation double differences is disclosed. The method comprises the following steps: 1) establishing a relative travel time target equation of the perforation signals for inversion by using the picked longitudinal and transverse travel times of the perforation micro seismic signals as an observed value to obtain an anisotropic velocity model; 2) using the longitudinal and transverse wave travel time of the microseism event as an observed value, jointly positioning a target equation according to the anisotropic longitudinal and transverse waves of the microseism event, inputting the initial positioning velocity model, and carrying out inversion of the space position of the microseism event; 3) and inverting the micro-seismic event space position again to obtain the relocated micro-seismic event space position and the corresponding corrected velocity model. According to the longitudinal and transverse wave combined positioning method based on the multiple perforation double differences, the overall radial and depth errors of the micro-seismic event are further reduced, and the positioning precision of the micro-seismic event is improved.

Description

Longitudinal and transverse wave combined positioning method based on multiple perforation double differences
Technical Field
The invention relates to the field of borehole microseism signal processing, in particular to a longitudinal wave and transverse wave combined positioning method based on multiple perforation double differences.
Background
The underground microseism monitoring is one of microseism observation modes and is characterized in that an underground three-component detector receives microseism full wavefield signals, and compared with ground microseism monitoring, the underground microseism monitoring system has the advantages that the signal-to-noise ratio of data received in a well is high, the number and types of microseism events are rich, but the defect is that the azimuth of the underground detector is unknown, so that the X-component microseism data and the Y-component microseism data of the detector are disordered, and subsequent positioning processing is influenced. Meanwhile, the observation distance of the micro-seismic in the well is short (generally about 200-1000 meters) and the number of detectors is limited (generally 12-32-level three-component in-well detectors), that is, the signal receiving range is too narrow, so that the micro-seismic positioning in some wells is easy to have the phenomena of instability, low precision and the like.
At present, the borehole microseism positioning technology mainly has two ideas: firstly, forward modeling is carried out when events of P waves and S waves travel, a representative algorithm comprises a network search method, a simulated annealing method, a geiger method and the like, the method has the advantages of easiness in realization and the defects that the events of the P waves and the S waves are difficult to accurately pick up when traveling due to weak first arrival phase signals, and positioning results are influenced; the second positioning idea is based on wave equation convolution, and the representative algorithm comprises an interference method, a reverse time migration method and a passive source imaging method.
The method is suitable for being based on isotropic uniform media, but in fracturing microseism development of unconventional tight sandstone gas and shale gas reservoir reservoirs, the stratum has heterogeneity and belongs to anisotropic media, and the travel time and the propagation path of longitudinal and transverse microseism waves are different from isotropy, so that the microseism event is inaccurately positioned by the conventional positioning method. In order to solve the problem, the invention provides a longitudinal and transverse wave combined positioning method based on multiple perforation double differences.
The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
Disclosure of Invention
According to the requirements of unconventional microseism monitoring of coal bed gas, shale gas and the like, the influence of stratum anisotropy on longitudinal and transverse wave travel time needs to be considered in the microseism positioning method in the well, and unstable and inaccurate positioning of microseism events is eliminated or reduced. The invention introduces the concept of multi-perforation and anisotropic medium into the double-difference method, provides a new positioning method, and eliminates the positioning error caused by the small number of detectors, single inversion speed and single perforation in the microseism as much as possible. Similar to the traditional method, firstly, carrying out anisotropic positioning analysis on a plurality of perforation holes to obtain a group of anisotropic velocity models which are in line with the plurality of perforation holes and have the smallest integral error as a stratum initial parameter model; then, directly positioning and processing the microseism event by using the positioning method of the invention to obtain the initial spatial position of the microseism event; and then, carrying out relocation by utilizing a chromatography thought and considering stratum non-mean, namely: and continuously correcting the anisotropic velocity model, and simultaneously inverting the space position of the microseism event until the travel time error is minimum, until a microseism event positioning result with higher precision is finally obtained.
The method for jointly positioning the longitudinal waves and the transverse waves based on the double differences of the multiple perforations comprises the following steps:
1) longitudinal wave travel time T of perforation micro seismic signal picked upshoot,PTransverse wave travel time Tshoot,SAs observed values, a longitudinal wave and transverse wave combined positioning target equation OPJ based on perforation positioning analysis is establishedshootPerforming inversion based on the anisotropy parameter value and the vertical longitudinal and transverse wave velocity value of the known perforation space position to obtain an initial positioning velocity model Vmodel＝{ε,δ,VP0,VS0}；
2) Using the travel time T of the longitudinal wave of a microseism eventevent,PTransverse wave travel time Tevent,SAs an observed value, an anisotropic longitudinal and transverse wave joint positioning target equation OPJ of the microseism event is establishedeventInputting the initial positioning velocity model VmodelDeveloping a microseismic event spatial location RTevent＝{Levent,ZeventInversion of where LeventIs the horizontal distance of microseismic events, ZeventIs the microseismic event depth distance;
3) at the microseismic event spatial location RTeventFor positioning the center, the initial positioning speed model V is positioned in a set rangemodelCorrection of anisotropy parameters while inverting the micro-mirror againObtaining the spatial position of the relocated microseismic event RT* event＝{L* event,Z* eventAnd the corresponding corrected velocity model V* model＝{ε*,δ*,VP0,VS0}，
Wherein, the longitudinal and transverse wave jointly positions the target equation OPJshootComprises the following steps:
OPJshoot＝OPJshoot,P+OPJshoot,PS+OPJshoot,S(1)，
microseismic event anisotropic longitudinal and transverse wave joint positioning target equation OPJeventComprises the following steps:
OPJevent＝OPJevent,shoot,P+OPJevent,shoot,PS+OPJevent,shoot,S(2)
equation (1) consists of three parts, namely a perforation longitudinal wave travel time positioning target equation OPJshoot,PEquation OPJ for positioning target of time difference of longitudinal and transverse wave travel of perforationshoot,PSAnd perforation shear wave travel time positioning target equation OPJshoot,S(ii) a The formula (2) also consists of three parts, namely a microseism event positioning target equation OPJ based on multi-perforation double-difference longitudinal wave travel timeevent,shoot,PMultiple perforation double-difference longitudinal and transverse wave travel time difference based positioning target equation OPJ for microseism eventevent,shoot,PSAnd positioning target equation OPJ based on multi-perforation double-difference shear wave travel time for microseismic eventsevent,shoot,S。
Preferably, the object equation OPJ is located jointly in the longitudinal and transverse wavesshootThe method comprises the following steps:
Figure BDA0001338898360000031
Figure BDA0001338898360000032
Figure BDA0001338898360000033
wherein the content of the first and second substances,
Figure BDA0001338898360000034
the longitudinal wave travel time and the transverse wave travel time of the picked perforation micro seismic signals are Tshoot,P、Tshoot,SAnd i is the serial number of the detector, and j is the serial number of the perforation respectively representing the longitudinal wave travel time and the transverse wave travel time of the inverted perforation micro seismic signal.
Preferably, the step 1) includes solving the following four equations simultaneously to calculate the anisotropic velocity model Vmodel＝{ε,δ,VP0,VS0}：
Figure BDA0001338898360000035
Figure BDA0001338898360000041
Figure BDA0001338898360000042
Figure BDA0001338898360000043
Preferably, equations (6) to (9) are solved by the least square method.
Preferably, target equation OPJ is located in the micro-seismic event anisotropic longitudinal and transverse wave combinationeventThe method comprises the following steps:
Figure BDA0001338898360000044
Figure BDA0001338898360000045
Figure BDA0001338898360000046
wherein the content of the first and second substances,
Figure BDA0001338898360000047
the true value of the travel time of the longitudinal wave, the true value of the travel time of the transverse wave and T are respectively picked up by the microseismic event of the ith detectorevent,P,i、Tevent,S,iRespectively are the longitudinal wave travel time inversion value and the transverse wave travel time inversion value of the microseism event of the ith detector,
Figure BDA0001338898360000048
the real values of the longitudinal wave travel time and the transverse wave travel time picked up by the ith detector of the jth perforation signal are respectively,
Figure BDA0001338898360000049
and respectively calculating a longitudinal wave travel time inversion value and a transverse wave travel time inversion value of the jth perforation signal and the ith detector.
Preferably, said step 2) comprises simultaneously solving the following two equations, calculating the microseismic event spatial location RTevent＝{Levent,Zevent}：
Figure BDA00013388983600000410
Figure BDA00013388983600000411
Preferably, equations (13) to (14) are solved by a grid search method:
perforation-based positioning speed model VmodelEstablishing grids, taking each grid position as a possible micro-seismic event position, and calculating the first arrival travel time T of the longitudinal and transverse waves of the micro-seismic event at each grid point by utilizing ray tracingevent,Pi、Tevent,SiCounting the error between the real values of the micro-seismic event observation and the grid position corresponding to the minimum error is the space position RT of the micro-seismic eventevent＝{Levent,Zevent}。
Preferably, the step 3) comprises solving the following four equations simultaneously to obtain the relocated microseismic event spatial location RT* event＝{L* event,Z* eventAnd the corresponding corrected velocity model V* model＝{ε*,δ*,VP0,VS0}：
Figure BDA0001338898360000051
Figure BDA0001338898360000052
Figure BDA0001338898360000053
Figure BDA0001338898360000054
Preferably, equations (15) to (18) are solved by a general grid search method:
establishing a grid by taking the space position of the microseism event as a center, and positioning an anisotropic velocity model V at the perforationmodelOn the basis, corresponding microseism event space positions are inverted for all possible values of the anisotropic parameters in a set range, longitudinal and transverse wave first-arrival travel time is correspondingly tracked through rays, the travel time error is calculated by comparing the travel time with a real observation travel time value, and the microseism event space position corresponding to the minimum value of the possible travel time error and the anisotropic parameters are determined as the relocated microseism event space position RT* event＝{L* event,Z* eventAnd the corresponding corrected velocity model V* model＝{ε*,δ*,VP0,VS0}。
According to the longitudinal and transverse wave combined positioning method based on the multiple perforation double differences, the overall radial and depth errors of the micro-seismic event are further reduced, and the positioning precision of the micro-seismic event is improved.
The method and apparatus of the present invention have other features and advantages which will be apparent from or are set forth in detail in the accompanying drawings and the following detailed description, which are incorporated herein, and which together serve to explain certain principles of the invention.
Drawings
The above and other objects, features and advantages of the present invention will become more apparent by describing in more detail exemplary embodiments thereof with reference to the attached drawings, in which like reference numerals generally represent like parts.
FIG. 1 is a flow chart of a multiple perforation double-difference-based compressional-shear wave joint location method according to an exemplary embodiment of the present invention;
FIG. 2 is a side view of a perforation, geophone, microseismic event view wherein ▲ represents a perforation, ◆ represents a geophone, and ● represents an event;
FIG. 3 is a schematic representation of the microseismic event location results of the present invention based on an initial formation parameter model of perforation location analysis;
FIG. 4 is a statistical representation of the positioning result error of FIG. 3;
FIG. 5 is a schematic illustration of the results of tomographic relocation of microseismic events using the present invention based on the initial results of FIG. 3;
fig. 6 is a positioning result error statistic of fig. 5.
Detailed Description
The invention will be described in more detail below with reference to the accompanying drawings. While the preferred embodiments of the present invention are shown in the drawings, it should be understood that the present invention 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 invention to those skilled in the art.
The invention provides a combined positioning method based on longitudinal and transverse wave travel time of an anisotropic medium, which comprises the following three steps: the first step is to develop a plurality of perforation links by taking the relative travel time of the anisotropic longitudinal and transverse waves as a target equationPerforming combined positioning analysis to obtain an anisotropic velocity model V corresponding to the minimum sum of absolute values of all perforation positioning errorsmodel＝{ε,δ,VP0,VS0}; the second step is to use the anisotropic velocity model of the first step of multi-perforation positioning analysis as an initial stratum model, and to adopt the multi-perforation double-difference longitudinal and transverse wave combined positioning method of the invention to directly position the microseism event to obtain the initial spatial distribution RTevent＝{Levent,Zevent}; the third step is to use the chromatography thinking to develop the positioning method of the invention for repositioning analysis, namely: centering on the positioning result of the microseism event of the second step and taking a velocity model VmodelThe positioning equation of the invention is used as a target equation for an initial stratum model, chromatography reprocessing is carried out on the microseism event, iteration is carried out continuously until a group of longitudinal and transverse wave travel time and observation true value errors are minimum, and thus a higher-precision positioning result RT of the microseism event is finally obtained* event＝{L* event,Z* eventAnd the corresponding corrected velocity model V* model＝{ε*,δ*,VP0,VS0}。
The following describes a flowchart of the method for jointly positioning longitudinal waves and transverse waves of an anisotropic medium in detail with reference to fig. 1. The method mainly comprises the following steps:
step 1: longitudinal wave travel time T of perforation micro seismic signal picked upshoot,PTransverse wave travel time Tshoot,SAs observed values, a longitudinal wave and transverse wave combined positioning target equation OPJ based on perforation positioning analysis is establishedshootPerforming inversion based on the anisotropy parameter value and the vertical longitudinal and transverse wave velocity value of the known perforation space position to obtain an initial positioning velocity model Vmodel＝{ε,δ,VP0,VS0}。
Longitudinal and transverse wave joint positioning target equation OPJshootComprises the following steps:
OPJshoot＝OPJshoot,P+OPJshoot,PS+OPJshoot,S(1)，
Figure BDA0001338898360000071
Figure BDA0001338898360000072
Figure BDA0001338898360000073
wherein the content of the first and second substances,
Figure BDA0001338898360000074
the longitudinal wave travel time and the transverse wave travel time of the picked perforation micro seismic signals are Tshoot,P、Tshoot,SThe longitudinal wave travel time and the transverse wave travel time of the inverted perforation micro seismic signals are respectively, i is the detector serial number, and j is the perforation serial number (representing the joint analysis of a plurality of perforation signals). Such as, for example,
Figure BDA0001338898360000075
the first arrival time of the longitudinal wave picked up by the ith geophone of the jth perforation is obtained.
By finding a suitable location velocity model VmodelSo that the target equation OPJ approaches to zero, and at this time, the location of the seismic source point corresponding to the travel time of the longitudinal and transverse waves is the inverted perforation location, and the mathematical expression is as follows:
Figure BDA0001338898360000076
Figure BDA0001338898360000077
Figure BDA0001338898360000081
Figure BDA0001338898360000082
equations (6) to (9) are typically solved using a least squares method, whichResult output anisotropic velocity model V based on perforation positioning analysismodel＝{ε,δ,VP0,VS0}。
Step 2: using the travel time T of the longitudinal wave of a microseism eventevent,PTransverse wave travel time Tevent,SAs an observed value, an anisotropic longitudinal and transverse wave joint positioning target equation OPJ of the microseism event is establishedeventInputting the initial positioning velocity model VmodelDeveloping a microseismic event spatial location RTevent＝{Levent,ZeventInversion of where LeventIs the horizontal distance of microseismic events, ZeventIs the microseismic event depth distance.
Namely, the longitudinal and transverse wave travel time of the microseism event is used as an observed value, and a multi-perforation double-difference anisotropy based longitudinal and transverse wave travel time combined positioning target equation OPJ is establishedeventInputting an initial positioning velocity model VmodelHorizontal distance L to develop microseismic eventseventA depth distance ZeventInversion is carried out, so that the absolute value of the time difference between the travel time of longitudinal and transverse waves in inversion and the observed value is minimum, and the initial positioning result RT of the microseism event is obtainedevent＝{Levent,Zevent}。
Supposing that the anisotropic parameters, the velocity and the like of the position of the microseism event are the same as the parameters of the perforation position, adopting a velocity model required by microseism event positioning, and adopting a parameter model VmodelThe real model is replaced, the travel time of the longitudinal and transverse waves of the picked micro-seismic event is taken as an observed value, and a multi-perforation double-difference longitudinal and transverse wave-based joint positioning target equation is established:
OPJevent＝OPJevent,shoot,P+OPJevent,shoot,PS+OPJevent,shoot,S(2)
Figure BDA0001338898360000083
Figure BDA0001338898360000084
Figure BDA0001338898360000085
wherein the content of the first and second substances,
Figure BDA0001338898360000086
the true value of the travel time of the longitudinal wave, the true value of the travel time of the transverse wave and T are respectively picked up by the microseismic event of the ith detectorevent,P,i、Tevent,S,iRespectively are the longitudinal wave travel time inversion value and the transverse wave travel time inversion value of the microseism event of the ith detector,
Figure BDA0001338898360000087
the real values of the longitudinal wave travel time and the transverse wave travel time picked up by the ith detector of the jth perforation signal are respectively,
Figure BDA0001338898360000091
and respectively calculating a longitudinal wave travel time inversion value and a transverse wave travel time inversion value of the jth perforation signal and the ith detector. Namely: the microseism event multi-perforation double-difference longitudinal and transverse wave target equation is expressed as the sum of multi-perforation P wave travel time double differences, multi-perforation PS wave time differences and multi-perforation S wave travel time double differences.
According to the assumption, the velocity model is now known, and the microseismic event localization is only an event space position radial and depth inversion process:
Figure BDA0001338898360000092
Figure BDA0001338898360000093
the two partial derivative equations can be solved by a common grid search method, namely: with perforation positioning velocity model VmodelFor reference, establishing a grid according to the positioning precision requirement; taking each grid position as a possible position of the micro-seismic event, and calculating the first arrival travel time T of the longitudinal and transverse waves of the micro-seismic event at each grid point by utilizing ray tracingevent,Pi、Tevent,SiBetween statistical and microseismic event observed true valuesFinding the grid position corresponding to the minimum error, namely the space position L of the microseism eventevent、Zevent。
And step 3: at the microseismic event spatial location RTeventFor positioning the center, the initial positioning speed model V is positioned in a set rangemodelCorrecting the anisotropic parameters, and simultaneously re-inverting the microseismic event space position to obtain a re-positioned microseismic event space position RT* event＝{L* event,Z* eventAnd the corresponding corrected velocity model V* model＝{ε*,δ*,VP0,VS0}。
Namely, the chromatography positioning processing of the microseism event is carried out, so as to obtain the microseism event space position RT with higher precision* eventAnd the corrected velocity model V* model。
Due to the fact that the anisotropy parameters of the positions of the micro-seismic events are slightly different from the positions of the perforations, the positioning of the micro-seismic events is carried out by using the perforation positioning anisotropic velocity model due to the difference, and the results of the positioning of the micro-seismic events deviate from the real event positions. To account for this difference, we propose anisotropic medium microseismic event tomographic localization with the objective equation like OPJ expressed in equation (2)event。
Except that in addition to inverting the microseismic event spatial location radial, depth, anisotropic parameters in the velocity model are inverted simultaneously, i.e.:
Figure BDA0001338898360000101
Figure BDA0001338898360000102
Figure BDA0001338898360000103
Figure BDA0001338898360000104
the four groups of partial derivative equations can be solved by a grid search method, and the concrete process is as follows: establishing a grid at the possible micro-seismic event position according to the precision requirement, and positioning an anisotropic velocity model V at the perforationmodelOn the basis, a certain value range [ epsilon-delta epsilon, epsilon + delta epsilon ] is given to the anisotropy parameters (epsilon, delta)]、[δ-Δδ,δ+Δδ]And (3) inverting the radial direction and depth of the corresponding micro-seismic event space position according to all possible values of epsilon and delta in the range, correspondingly ray-tracing the first-arrival travel time of longitudinal and transverse waves, comparing the first-arrival travel time with the real observation travel time value, calculating travel time errors, searching for all possible travel time errors, and obtaining the corresponding micro-seismic event space position and anisotropic parameters, namely the final inverted event chromatography positioning result RT* event＝{L* event,Z* eventAnd its corrected velocity model V* model＝{ε*,δ*,VP0,VS0}。
Application example
To facilitate understanding of the solution of the embodiments of the present invention and the effects thereof, 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.
The accuracy of the anisotropic medium longitudinal and transverse wave combined positioning method is verified by using borehole microseism model data.
The microseism observation example in the well is that a 14-grade underground detector monitors microseism signals, 3 known perforation signals and 19 event signals, the geometrical relationship of radial and depth coordinates of an observation system is shown in figure 2, and table 1 shows anisotropic parameters epsilon and delta corresponding to different seismic source point positions.
TABLE 1 anisotropy parameters for different seismic source point positions
Figure BDA0001338898360000111
The invention is verified by using a high-precision ray tracing algorithm and taking the time when each seismic source point reaches the longitudinal and transverse wave travel of the detector as the input of a known observation value according to the observation mode of the figure 2 and the anisotropy parameter table 1.
Firstly, according to the formulas (1) to (8), anisotropic longitudinal and transverse wave combined positioning analysis of the known perforation positions is carried out. The travel time of a plurality of perforation longitudinal and transverse waves is picked up as an observed value, a combined positioning target equation of a plurality of perforation longitudinal and transverse waves of the anisotropic medium relative travel time is established, a group of anisotropic parameters and longitudinal and transverse wave speeds are searched through continuous inversion, the sum of absolute values of all perforation positioning errors of the combination is minimum, a target equation set (formulas (5) to (8)) is solved through a least square method, and an anisotropic speed model based on perforation positioning analysis is obtained, and is shown in table 2.
TABLE 2 Anisotropic velocity model
Parameters of the perforated formation True value Inversion value
Vertical longitudinal wave velocity VP0(m/s) 3028 3010
Vertical transverse wave velocity VS0(m/s) 1488 1499
Anisotropy parameter ε 0.255 0.263
Anisotropy parameter delta -0.05 -0.07
Then, the anisotropic velocity model is used as an initial stratum parameter model, the microseism event is directly positioned according to the formulas (2), (10) and (12), the formulas (13) to (14) are solved by a grid method, the optimal space position of the seismic source is found, the corresponding longitudinal and transverse wave travel time is enabled to be closest to a real value, and the optimal position of the seismic source at the moment is used as the initial positioning result of the next step. FIG. 3 is an anisotropic model based on multiple perforation placement analysis with some error in the direct placement of microseismic events of the present invention, as shown in FIG. 4, where the left side dLx represents the radial error and the right side dZx represents the depth error for each set of data. This indicates that the difference in anisotropy at different locations will cause some degree of positioning error.
Finally, in order to further improve the positioning accuracy, on the basis of the primary positioning result, the formulas (2), (10) to (12) of the invention are utilized, a chromatography thought is adopted, namely, the initial result is taken as the center, a numerical range is given, the space position and the anisotropy of the microseism event are inverted simultaneously until the longitudinal and transverse wave travel time is infinitely close to the observation true value, and the grid method partial derivation formulas (15) to (18) are used, so that the accurate positioning of the microseism event is finally realized, as shown in fig. 5. The positioning result error statistics of fig. 6 shows that the overall radial and depth errors of the microseism event are further reduced by the multi-perforation double-difference combined positioning, and the microseism positioning effect of the invention is verified.
It will be appreciated by persons skilled in the art that the above description of embodiments of the invention is intended only to illustrate the benefits of embodiments of the invention and is not intended to limit embodiments of the invention to any examples given.
Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. 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 terminology used herein is chosen in order to best explain the principles of the embodiments, the practical application, or improvements made to the technology in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

Claims (7)

1. A longitudinal and transverse wave combined positioning method based on multiple perforation double differences is characterized by comprising the following steps:
1) longitudinal wave travel time of perforation micro seismic signal picked up
Figure FDA0002356939480000011
Transverse wave travel time
Figure FDA0002356939480000012
As observed values, a longitudinal wave and transverse wave combined positioning target equation OPJ based on perforation positioning analysis is establishedshootPerforming inversion based on the anisotropy parameter value and the vertical longitudinal and transverse wave velocity value of the known perforation space position to obtain an initial positioning velocity model Vmodel＝{ε,δ,VP0,VS0}；
2) Using longitudinal wave travel time of microseism event
Figure FDA0002356939480000013
Transverse wave travel time
Figure FDA0002356939480000014
As an observed value, an anisotropic longitudinal and transverse wave joint positioning target equation OPJ of the microseism event is establishedeventInputting the initial positioning velocity model VmodelDeveloping a microseismic event spatial location RTevent＝{Levent,ZeventInversion of where LeventIs the horizontal distance of microseismic events, ZeventIs the microseismic event depth distance;
3) at the microseismic event spatial location RTeventFor positioning the center, the initial positioning speed model V is positioned in a set rangemodelCorrecting the anisotropic parameters, and simultaneously re-inverting the microseismic event space position to obtain the re-positioned microseismic event space position
Figure FDA0002356939480000015
And a corresponding corrected velocity model V* model＝{ε*,δ*,VP0,VS0}，
Wherein, the longitudinal and transverse wave jointly positions the target equation OPJshootComprises the following steps:
OPJshoot＝OPJshoot,P+OPJshoot,PS+OPJshoot,S(1)，
microseismic event anisotropic longitudinal and transverse wave joint positioning target equation OPJeventComprises the following steps:
OPJevent＝OPJevent,shoot,P+OPJevent,shoot,PS+OPJevent,shoot,S(2)
equation (1) consists of three parts, namely a perforation longitudinal wave travel time positioning target equation OPJshoot,PEquation OPJ for positioning target of time difference of longitudinal and transverse wave travel of perforationshoot,PSAnd perforation shear wave travel time positioning target equation OPJshoot,S(ii) a The formula (2) also consists of three parts, namely a microseism event positioning target equation OPJ based on multi-perforation double-difference longitudinal wave travel timeevent,shoot,PMultiple perforation double-difference longitudinal and transverse wave travel time difference based positioning target equation OPJ for microseism eventevent,shoot,PSAnd microseismic event positioning target equation OPJ based on multi-perforation double-difference transverse wave travel timeevent,shoot,S；
Wherein the target equation OPJ is located in the longitudinal and transverse wave combination based on the perforation location analysisshootThe method comprises the following steps:
Figure FDA0002356939480000021
Figure FDA0002356939480000022
Figure FDA0002356939480000023
wherein the content of the first and second substances,
Figure FDA0002356939480000024
the longitudinal wave travel time and the transverse wave travel time of the picked perforation micro seismic signals are Tshoot,P、Tshoot,SRespectively representing longitudinal wave travel time and transverse wave travel time of the inverted perforation micro seismic signal, wherein i is a detector serial number, and j is a perforation serial number;
jointly locating object equations OPJ in the micro-seismic event anisotropic longitudinal and transverse waveseventThe method comprises the following steps:
Figure FDA0002356939480000025
Figure FDA0002356939480000026
Figure FDA0002356939480000027
wherein the content of the first and second substances,
Figure FDA0002356939480000028
the true value of the travel time of the longitudinal wave, the true value of the travel time of the transverse wave and T are respectively picked up by the microseismic event of the ith detectorevent,P,i、Tevent,S,iRespectively are the longitudinal wave travel time inversion value and the transverse wave travel time inversion value of the microseism event of the ith detector,
Figure FDA0002356939480000029
the real values of the longitudinal wave travel time and the transverse wave travel time picked up by the ith detector of the jth perforation signal are respectively,
Figure FDA00023569394800000210
and respectively calculating a longitudinal wave travel time inversion value and a transverse wave travel time inversion value of the jth perforation signal and the ith detector.
2. The method for joint positioning of longitudinal waves and transverse waves based on multiple perforations and double differences as claimed in claim 1, wherein the step 1) comprises solving the following four equations simultaneously to calculate an anisotropic velocity model Vmodel＝{ε,δ,VP0,VS0}：
Figure FDA0002356939480000031
Figure FDA0002356939480000032
Figure FDA0002356939480000033
Figure FDA0002356939480000034
Wherein OPJ-OPJshootAnd a longitudinal and transverse wave combined positioning target equation is formed.
3. The method of claim 2, wherein equations (6) - (9) are solved by least squares.
4. The method for joint positioning of longitudinal waves and transverse waves based on multiple perforation double differences as claimed in claim 1, wherein the step 2) comprises solving the following two equations simultaneously to calculate the space position RT of the microseismic eventevent＝{Levent,Zevent}：
Figure FDA0002356939480000035
Figure FDA0002356939480000036
5. The method for joint positioning of longitudinal and transverse waves based on multiple perforations and double differences as claimed in claim 4, wherein equations (13) to (14) are solved by a grid search method:
perforation-based positioning speed model VmodelEstablishing grids, taking each grid position as a possible micro-seismic event position, and calculating the first arrival travel time T of the longitudinal and transverse waves of the micro-seismic event at each grid point by utilizing ray tracingevent,Pi、Tevent,SiCounting the error between the real values of the micro-seismic event observation and the grid position corresponding to the minimum error is the space position RT of the micro-seismic eventevent＝{Levent,Zevent}。
6. The method for joint positioning of longitudinal and transverse waves based on multiple perforations and double differences as claimed in claim 5, wherein the step 3) comprises solving the following four equations simultaneously to obtain the repositioned micro-seismic event spatial position RT* event＝{L* event,Z* eventAnd the corresponding corrected velocity model V* model＝{ε*,δ*,VP0,VS0}：
Figure FDA0002356939480000041
Figure FDA0002356939480000042
Figure FDA0002356939480000043
Figure FDA0002356939480000044
7. The method for joint positioning of longitudinal waves and transverse waves based on multiple perforations and double differences as claimed in claim 6, wherein the equations (15) - (18) are solved by a general grid search method:
establishing a grid by taking the space position of the microseism event as a center, and positioning an anisotropic velocity model V at the perforationmodelOn the basis, corresponding microseism event space positions are inverted for all possible values of the anisotropic parameters in a set range, longitudinal and transverse wave first-arrival travel time is correspondingly tracked through rays, the travel time error is calculated by comparing the travel time with a real observation travel time value, and the microseism event space position corresponding to the minimum value of the possible travel time error and the anisotropic parameters are determined as the relocated microseism event space position RT* event＝{L* event,Z* eventAnd the corresponding corrected velocity model V* model＝{ε*,δ*,VP0,VS0}。
CN201710528514.8A 2017-07-01 2017-07-01 Longitudinal and transverse wave combined positioning method based on multiple perforation double differences Active CN109212593B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201710528514.8A CN109212593B (en) 2017-07-01 2017-07-01 Longitudinal and transverse wave combined positioning method based on multiple perforation double differences

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201710528514.8A CN109212593B (en) 2017-07-01 2017-07-01 Longitudinal and transverse wave combined positioning method based on multiple perforation double differences

Publications (2)

Publication Number Publication Date
CN109212593A CN109212593A (en) 2019-01-15
CN109212593B true CN109212593B (en) 2020-06-23

Family

ID=64991815

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201710528514.8A Active CN109212593B (en) 2017-07-01 2017-07-01 Longitudinal and transverse wave combined positioning method based on multiple perforation double differences

Country Status (1)

Country Link
CN (1) CN109212593B (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2539745C1 (en) * 2013-08-28 2015-01-27 Федеральное государственное бюджетное учреждение науки Институт проблем нефти и газа РАН Method for seismic monitoring when developing hydrocarbon deposits at water areas
CN105116444A (en) * 2015-08-24 2015-12-02 电子科技大学 Ground microseism monitoring anisotropy speed model
CN105510880A (en) * 2014-09-23 2016-04-20 中国石油化工股份有限公司 Microseism focus positioning method based on double-difference method
CN105589100A (en) * 2014-10-21 2016-05-18 中国石油化工股份有限公司 Micro-seismic source location and velocity model simultaneous inversion method

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2539745C1 (en) * 2013-08-28 2015-01-27 Федеральное государственное бюджетное учреждение науки Институт проблем нефти и газа РАН Method for seismic monitoring when developing hydrocarbon deposits at water areas
CN105510880A (en) * 2014-09-23 2016-04-20 中国石油化工股份有限公司 Microseism focus positioning method based on double-difference method
CN105589100A (en) * 2014-10-21 2016-05-18 中国石油化工股份有限公司 Micro-seismic source location and velocity model simultaneous inversion method
CN105116444A (en) * 2015-08-24 2015-12-02 电子科技大学 Ground microseism monitoring anisotropy speed model

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Locating Bakken microseismic events with simultaneous anisotropic tomography and extended double-difference method;Junlun Li;《SEG Houston 2013 Annual Meeting》;20131231;第2073-2078页 *
Microseismic event location using an inverse method of joint P-S phase arrival difference and P-wave arrival difference in a borehole system;Wen Zhou 等;《Journal of Geophysics and Engineering》;20150310;第12卷;第220-226页 *
Microseismic joint location and anisotropic velocity inversion for hydraulic fracturing in a tight Bakken reservoir;Junlun Li 等;《GEOPHYSICS》;20140721;第79卷(第5期);第C111-C122页 *

Also Published As

Publication number Publication date
CN109212593A (en) 2019-01-15

Similar Documents

Publication Publication Date Title
CN107817516B (en) Near-surface modeling method and system based on first-motion wave information
CN109085642B (en) Anisotropic medium microseism event positioning method
CN110687602A (en) Shallow seismic multi-wave combined exploration method
CN104570106A (en) Near-surface tomographic velocity analysis method
CN104360396B (en) A kind of three kinds of preliminary wave Zoumaling tunnel methods of TTI medium between offshore well
CN105607119B (en) Near-surface model construction method and static correction value acquiring method
CN106199704B (en) A kind of Three-dimendimal fusion submarine cable seismic data velocity modeling method
CN109212594B (en) Combined positioning method for longitudinal waves and transverse waves of anisotropic medium
CN110515122B (en) Forward grid search positioning and micro-seismic signal identification method and device
CN113960532A (en) Microseism positioning method based on secondary positioning calculation of imaginary source
CN109212593B (en) Longitudinal and transverse wave combined positioning method based on multiple perforation double differences
CN108693560A (en) A kind of scattering wave imaging method and system based on cross-correlation road
CN111580165A (en) Device and method for positioning arrival time difference of ocean bottom seismograph
CN107765306A (en) A kind of VSP initial velocities modeling method and device
CN116755148A (en) Orthogonal anisotropic medium multidirectional reflection wave travel time inversion method
CN110764136B (en) Combined positioning method for time-lapse linear combination and nonlinear combination of anisotropic longitudinal and transverse waves
CN110764140B (en) Perforation double-difference anisotropy based longitudinal and transverse wave nonlinear combined positioning method
CN110764148B (en) Well-ground combined positioning method for anisotropic vector wave field
CN109655892B (en) Combined positioning method and system of anisotropic longitudinal and transverse wave travel time ternary polynomial
CN105259577B (en) A kind of method and device for the angle information for determining bed boundary
CN109655919B (en) Anisotropic longitudinal and transverse wave travel time point multiplication positioning method and system
CN110764137B (en) Anisotropy longitudinal and transverse wave nonlinear combined positioning method based on perforation mixed time difference
CN110764138B (en) Anisotropy longitudinal and transverse wave travel time nonlinear combined positioning method
CN110764139B (en) Anisotropy longitudinal and transverse wave travel time high-order power linear combination positioning method
CN103576188B (en) A kind of seismic source location method of release rate error impact

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant