CN117172361A - Pre-drilling lithology prediction method and system - Google Patents
Pre-drilling lithology prediction method and system Download PDFInfo
- Publication number
- CN117172361A CN117172361A CN202311093158.3A CN202311093158A CN117172361A CN 117172361 A CN117172361 A CN 117172361A CN 202311093158 A CN202311093158 A CN 202311093158A CN 117172361 A CN117172361 A CN 117172361A
- Authority
- CN
- China
- Prior art keywords
- well
- drilling
- stratum
- time difference
- occurrence frequency
- 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.)
- Pending
Links
- 238000005553 drilling Methods 0.000 title claims abstract description 106
- 238000000034 method Methods 0.000 title claims abstract description 39
- 230000015572 biosynthetic process Effects 0.000 claims abstract description 102
- 238000012545 processing Methods 0.000 claims abstract description 22
- 239000011435 rock Substances 0.000 claims abstract description 18
- 235000019738 Limestone Nutrition 0.000 claims abstract description 14
- 239000006028 limestone Substances 0.000 claims abstract description 14
- -1 coarse sandstone Substances 0.000 claims abstract description 11
- 238000005755 formation reaction Methods 0.000 claims description 101
- 238000012937 correction Methods 0.000 claims description 28
- 238000010586 diagram Methods 0.000 claims description 15
- 229910052612 amphibole Inorganic materials 0.000 claims description 3
- 238000004364 calculation method Methods 0.000 claims description 3
- 239000010438 granite Substances 0.000 claims description 3
- 238000010276 construction Methods 0.000 claims description 2
- 230000010485 coping Effects 0.000 abstract description 2
- 238000004590 computer program Methods 0.000 description 4
- 238000010606 normalization Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 2
- 230000003044 adaptive effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Geophysics And Detection Of Objects (AREA)
Abstract
The invention discloses a pre-drilling lithology prediction method and a pre-drilling lithology prediction system, which belong to the technical field of drilling geophysical exploration, wherein the method comprises the following steps: collecting operation data of a drilled well of an oil field in a target area, wherein the operation data comprise drilling data, logging data and logging data; determining a main type of complex situation in which the oil field in the target area is drilled; carrying out standardization processing on the logging data to construct standardized logging data; determining lithology at the formation where the complex situation occurs; and acquiring geophysical elasticity parameters of the stratum of the well drilled in the target area according to the standardized logging data, identifying and stripping igneous rock, coarse sandstone, limestone fine sandstone, mudstone, fine sandstone and medium sandstone one by one, and establishing a lithology prediction template based on the geophysical elasticity parameters. The invention discloses a pre-drilling lithology prediction method which can accurately predict lithology sections of complex stratum and can be used for preparing a coping plan for future drilling of a target area.
Description
Technical Field
The invention relates to the technical field of drilling geophysical exploration, in particular to a pre-drilling lithology prediction method and system.
Background
The geological environment facing the well drilling is increasingly complex, the oil and gas exploration and development environment gradually turns to deep water and high temperature and high pressure, and the lithology of deep complex stratum needs to be fully mastered before the well drilling, so that the well drilling safety and smoothness are ensured. The conventional method for predicting lithology before well drilling generally divides stratum according to seismic reflection interfaces, and utilizes stratum and lithology logging information of a drilled well in a region, so that the lithology of the stratum is the same, the lithology distribution of the stratum in the whole region is determined by transverse extension, geophysical data are not introduced, and the method is only applicable to the region with simple and gentle structure. For areas with complex structures, due to lithology pinch-out or fault, the error of the prediction result of the traditional method is larger, and the subsequent drilling operation is seriously affected by the inaccurate lithology prediction.
Disclosure of Invention
Aiming at the problems, the invention aims to provide a pre-drilling lithology prediction method and a pre-drilling lithology prediction system, which are used for solving the problems that the error of a prediction result is large, and the subsequent drilling operation is seriously affected by the lithology prediction inaccuracy in the traditional method.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
in a first aspect, the invention discloses a pre-drilling lithology prediction method, which comprises the following steps:
Collecting operation data of a drilled well of an oil field in a target area, wherein the operation data comprise drilling data, logging data and logging data;
counting the types and the quantity of the complex situations of the well drilled in the oil field of the target area according to the well drilling data, summarizing the statistics results of the duty ratio of the types of the complex situations of the well drilled in the oil field of the target area, and determining the main types of the complex situations of the well drilled in the oil field of the target area;
carrying out standardization processing on the logging data to construct standardized logging data;
determining lithology of the stratum where the complex situation occurs by comparing the stratum where the complex situation occurs with lithology of the stratum where the complex situation occurs according to the logging data, the main type and the duty ratio of the complex situation of the oil field drilled in the target area and the standardized logging data;
obtaining geophysical elasticity parameters of the stratum of the well drilled in the target area according to the standardized logging data; reading stratum lithology according to the well logging data of the well drilling, drawing an elastic parameter intersection diagram of the whole drilling depth, respectively selecting one or two sensitive elastic parameters capable of reflecting lithology from geophysical elastic parameters of the stratum of the well drilling of the target area according to the elastic parameter intersection diagram of the whole drilling depth, identifying and stripping igneous rock, coarse sandstone, limestone, calcareous fine sandstone, mudstone, fine sandstone and medium sandstone one by one, and establishing a lithology prediction template based on the geophysical elastic parameters.
Preferably, the construction of the normalized logging data specifically includes the following steps:
establishing a frequency distribution diagram of the well logging data of the exploratory well according to the well logging data, and checking and confirming whether all the well logging data of the exploratory well meet the unified standard;
formations with nonstandard logging data caused by different logging ages and instrumentsNatural gamma G R Formation density ρ, longitudinal wave time difference T A Time difference of transverse wave T S And carrying out standardized correction, and constructing standardized logging data together with other logging data meeting unified standards.
Specifically, the formation natural gamma G R The standardization of (c) specifically comprises the following steps:
firstly, selecting a well which is the latest in logging time and most common in logging instruments in a drilled well in a target area as a reference well, and determining a stratum natural gamma value G with the highest occurrence frequency of the reference well R (reference);
secondly, according to the stratum natural gamma value G with the highest occurrence frequency of the reference well R (benchmark) determining the difference ΔG of the natural gamma values of the stratum with the highest occurrence frequency between the i well and the reference well R (i) The expression is as follows;
ΔG R (i)＝G R (i)-G R (reference) (1)
In the formula, deltaG R (i) The difference value of the natural gamma value of the stratum with the highest occurrence frequency between the i well and the reference well is obtained;
G R The (reference) is the stratum natural gamma value with the highest occurrence frequency of the reference well;
G R (i) The natural gamma value of the stratum with the highest occurrence frequency of the i well is obtained;
finally, according to the difference delta G of the natural gamma values of the stratum with the highest occurrence frequency between the i well and the reference well R (i) Correcting all stratum natural gamma of the i well, wherein the correction formula is as follows:
G' R (i,j)＝G R (i,j)-ΔG R (i) (2)
in the formula, G' R (i, j) is the corrected natural gamma value of the j-th formation of the i-well;
G R (i, j) is the natural gamma value of the j-th stratum of the i-well before correction;
ΔG R (i) Is the difference in natural gamma value of the formation with the highest frequency of occurrence between the i-well and the reference well.
Specifically, the normalization of the formation density ρ specifically includes the steps of:
firstly, selecting a well which is the latest in logging time and most common in logging instruments in a drilled well in a target area as a reference well, and determining stratum density rho (reference) with the highest occurrence frequency of the reference well;
secondly, according to the stratum density rho (reference) with the highest occurrence frequency of the reference well and the stratum density rho (i) with the highest occurrence frequency of the i well, obtaining a difference value Deltarho (i) of the stratum density with the highest occurrence frequency between the i well and the reference well, wherein the expression is as follows;
Δρ (i) =ρ (i) - ρ (reference) (3)
Where Δρ (i) is the difference in formation density between the i-well and the reference well with the highest frequency of occurrence;
ρ (reference) is the natural gamma value of the stratum with the highest occurrence frequency of the reference well;
ρ (i) is the formation density with the highest occurrence frequency of the i-well;
finally, correcting all stratum densities of the i well according to a difference Deltaρ (i) of stratum densities with the highest occurrence frequency between the i well and the reference well, wherein a correction formula is as follows:
ρ'(i,j)＝ρ(i,j)-Δρ(i) (4)
wherein ρ' (i, j) is the corrected i-well jth formation density;
ρ (i, j) is the j-th formation density of the i-well prior to correction;
Δρ (i) is the difference in formation density between the i well and the reference well where the frequency is greatest.
Specifically, the longitudinal wave time difference T A The standardization of (c) specifically comprises the following steps:
firstly, selecting a well which is the latest in logging time and most common in logging instruments in a drilled well in a target area as a reference well, and determining a longitudinal wave time difference T with the most frequency of occurrence of the reference well A (reference);
secondly, according to the longitudinal wave time difference T with the highest occurrence frequency of the reference well A Longitudinal wave time difference T with the highest occurrence frequency of (reference) and i-well A (reference) determining the difference DeltaT of the longitudinal wave time difference with the highest occurrence frequency between the i-well and the reference well A (i) The expression is as follows;
ΔT A (i)＝T A (i)-T A (reference) (5)
In the formula DeltaT A (i) The difference value of the longitudinal wave time difference with the highest occurrence frequency between the i well and the reference well is obtained;
T A The (reference) is the longitudinal wave time difference value with the highest occurrence frequency of the reference well;
T A (i) The longitudinal wave time difference with the highest occurrence frequency of the i well is obtained;
finally, according to the difference value delta T of the longitudinal wave time difference with the highest occurrence frequency between the i well and the reference well A (i) Correcting all longitudinal wave time differences of the i well, wherein the correction formula is as follows:
T' A (i,j)＝T A (i,j)-ΔT A (i) (6)
wherein T' A (i, j) is the j-th longitudinal wave time difference of the corrected i-well;
T A (i, j) is the j-th longitudinal wave time difference of the i-well before correction;
ΔT A (i) The difference between the longitudinal wave time differences with the highest occurrence frequency between the i well and the reference well.
In particular, the transverse wave time difference T S The standardization of (c) specifically comprises the following steps:
first, a well with the latest logging time and the most common logging instrument in a drilled well in a target area is selected as a reference well, and a transverse wave time difference T with the most frequency of occurrence of the reference well is determined S (reference);
second, according to the transverse wave time difference T with the highest occurrence frequency of the reference well S Transverse wave time difference T with highest frequency of occurrence of (reference) and i-well S (reference) determining the difference DeltaT of the transverse wave time difference with the highest occurrence frequency between the i-well and the reference well S (i) The expression is as follows;
ΔT S (i)＝T S (i)-T S (reference) (7)
In the formula DeltaT S (i) The difference value of the transverse wave time difference with the highest occurrence frequency between the i well and the reference well is obtained;
T S (benchmark) is the most frequent occurrence of a reference well A large difference in transverse wave time;
T S (i) The transverse wave time difference with the highest occurrence frequency of the i well is the same as that of the i well;
finally, according to the difference value delta T of transverse wave time difference with the highest occurrence frequency between the i well and the reference well S (i) Correcting all transverse wave time differences of the i well, wherein the correction formula is as follows:
T' S (i,j)＝T S (i,j)-ΔT S (i) (8)
wherein T' S (i, j) is the corrected j-th transverse wave time difference of the i-well;
T S (i, j) is the j-th shear wave time difference of the i-well before correction;
ΔT S (i) Is the difference in transverse wave time difference between the i well and the reference well with the highest occurrence frequency.
Preferably, the obtaining the geophysical elastic parameters of the stratum of the well drilled in the target area according to the standardized logging data specifically comprises the following steps:
firstly, normalized formation density rho ' and normalized formation natural gamma G ' are obtained ' R Normalized longitudinal wave time difference T' A Normalized transverse wave time difference T' S ；
Then, based on the normalized formation density ρ ', the normalized formation natural gamma G' R Normalized longitudinal wave time difference T' A Normalized transverse wave time difference T' S Calculating geophysical elastic parameters of a formation in a target zone that has been drilled, including transverse wave impedance I S Impedance of longitudinal wave I A Poisson's ratio v, elastic wave impedance I G Mei Jishu L and pull Mei Jishu L ambda The calculation formula is as follows:
wherein ρ' is the normalized formation density; t'. A The time difference of the longitudinal wave is normalized; t'. S The time difference is the normalized transverse wave time difference; i S Is transversal wave impedance; i A Is the longitudinal wave impedance; v is poisson's ratio; k is an intermediate value;G I is elastic wave impedance;the minimum value of the normalized longitudinal wave time difference; />Is the minimum value of the normalized transverse wave time difference; ρ' min Is the minimum value of the normalized formation density; i A Is the longitudinal wave impedance; i S Is transversal wave impedance; l (L) ambda Is pull Mei Jishu.
Preferably, the step of identifying and stripping igneous rock, coarse sandstone, limestone, calcareous fine sandstone, mudstone, fine sandstone and medium sandstone one by one specifically comprises the following steps:
step 1: first according to the longitudinal wave impedance I A >11000g/cm 3 M/s and transverse wave impedance I S >6000g/cm 3 M/s identifying and stripping out igneous rock formations including granite, basalt, amphibole, breccia, tuff;
step 2: identifying and stripping coarse sandstone in the remaining formations other than the igneous rock formation according to poisson ratio v < 0.23;
step 3: in the remaining formation, according to 8500g/cm 3 ·m/s<Elastic wave impedance G I <9500g/cm 3 M/s identifying and stripping off limestone;
step 4: in the remaining formation according to Law Mei Jishu L ambda >Identifying and stripping out calcareous fine sandstone by 25 GPa;
step 5: in the remaining formation, according to the formation density ρ >2.53g/cm 3 Identifying and stripping out mudstone;
step 6: in the remaining stratum, according to the longitudinal wave impedance I A >11000g/cm 3 M/s identification and stripping of fine sandstone;
step 7: the last remaining is medium sandstone.
Further, the method disclosed by the invention further comprises the following steps:
and obtaining a geophysical elastic parameter profile of the target area without drilling by utilizing seismic inversion, establishing a lithology prediction profile of the target area without drilling by setting a quantitative threshold according to the lithology prediction template based on the geophysical elastic parameter, and carrying out lithology prediction of the target area without drilling.
In a second aspect, the invention discloses a pre-drilling lithology prediction device, comprising
The first processing unit is used for collecting operation data of drilled wells of the oil field in the target area, including drilling data, logging data and logging data;
the second processing unit is used for counting the types and the quantity of the complex situations of the well drilled in the oil field in the target area according to the well drilling data, summarizing the statistics results of the duty ratio of the types of the complex situations of the well drilled in the oil field in the target area, and determining the main types of the complex situations of the well drilled in the oil field in the target area;
the third processing unit is used for carrying out standardization processing on the logging data and constructing standardized logging data;
The fourth processing unit is used for comparing the formation of the uncomplicated situation with the lithology of the formation where the complex situation occurs according to the logging information, the main type and the duty ratio of the complex situation of the oil field in the target area, and the standardized logging data;
a fifth processing unit, configured to obtain a geophysical elastic parameter of a formation in which the target area has been drilled according to the normalized logging data; reading stratum lithology according to the well logging data of the well drilling, drawing an elastic parameter intersection diagram of the whole drilling depth, respectively selecting one or two sensitive elastic parameters capable of reflecting lithology from geophysical elastic parameters of the stratum of the well drilling of the target area according to the elastic parameter intersection diagram of the whole drilling depth, identifying and stripping igneous rock, coarse sandstone, limestone, calcareous fine sandstone, mudstone, fine sandstone and medium sandstone one by one, and establishing a lithology prediction template based on the geophysical elastic parameters.
Compared with the prior art, the invention has the beneficial effects that:
firstly, collecting operation data of a drilled well of an oil field in a target area, including drilling data, logging data and logging data; counting the types and the quantity of the complex situations of the well drilled in the oil field of the target area according to the well drilling data, summarizing the statistics results of the duty ratio of the types of the complex situations of the well drilled in the oil field of the target area, and determining the main types of the complex situations of the well drilled in the oil field of the target area; carrying out standardization processing on the logging data to construct standardized logging data; determining lithology of the stratum where the complex situation occurs by comparing the stratum where the complex situation occurs with lithology of the stratum where the complex situation occurs according to the logging data, the main type and the duty ratio of the complex situation of the oil field drilled in the target area and the standardized logging data; obtaining geophysical elasticity parameters of the stratum of the well drilled in the target area according to the standardized logging data; reading stratum lithology according to the well logging data of the well drilling, drawing an elastic parameter intersection chart of the whole drilling depth, respectively selecting one or two sensitive elastic parameters capable of reflecting lithology from geophysical elastic parameters of the stratum of the well drilling of the target area according to the elastic parameter intersection chart of the whole drilling depth, identifying and stripping igneous rock, coarse sandstone, limestone, calcareous fine sandstone, mudstone, fine sandstone and medium sandstone one by one, and establishing a lithology prediction template based on the geophysical elastic parameters; and obtaining a geophysical elastic parameter profile of the target area without drilling by utilizing seismic inversion, establishing a lithology prediction profile of the target area without drilling by setting a quantitative threshold according to the lithology prediction template based on the geophysical elastic parameter, and carrying out lithology prediction of the target area without drilling. The invention discloses a pre-drilling lithology prediction method, which is used for solving the problems that the prediction result error is large, and the lithology prediction is not accurate and the subsequent drilling operation is seriously affected by the prior method.
The pre-drilling lithology prediction method is suitable for deep ultra-deep drilling engineering of areas such as offshore, land and polar regions, and is used for accurately predicting the lithology section of a complex stratum through drilling, logging and seismic data in the pre-drilling stage, so as to prepare a coping plan for future drilling of the area. For example, an anti-seize plan is made in advance in the easy seize stratum, and the adaptive drill bit is replaced in advance in the difficult stratum to lift the mechanical drilling speed.
Drawings
FIG. 1 is a lithology prediction template based on geophysical elastic parameters according to an embodiment of the present invention; wherein, fig. 1 (a) is a diagram showing the intersection between the transversal wave impedance and the longitudinal wave impedance; FIG. 1 (b) is a plot of the intersection between Poisson's ratio and the natural gamma of the formation; FIG. 1 (c) is a graph of the intersection between elastic wave impedance and the natural gamma of the formation; FIG. 1 (d) is a plot of the intersection between Law Mei Jishu and the natural gamma of the formation; FIG. 1 (e) is a plot of the intersection between formation density and the natural gamma of the formation; FIG. 1 (f) is a graph of the intersection between the longitudinal wave impedance and the natural gamma of the formation; FIG. 1 (g) is a diagram of igneous and sedimentary rocks;
fig. 2 is a pre-drilling predicted lithology section of a target area according to an embodiment of the present invention.
Detailed Description
Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary 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.
In the prior art, the lithology prediction method before oil field development well drilling generally divides the stratum according to the seismic reflection interface, and then considers that the lithology of the stratum is the same according to the logging data of the lithology of the stratum of the drilled well in the target area, and the lithology distribution of the stratum in the whole area is determined by transverse extension. The prior art does not introduce geophysical data, is applicable to a region with simple and gentle structure, but is applicable to a region with complex structure, such as lithology pinch-out, fault activity, fault section of stratum and larger lithology distribution prediction result error.
The pre-drilling lithology prediction method and system disclosed by the invention comprehensively use the drilling data, logging data and regional seismic data of the exploratory well, and find out the main types and corresponding lithology of the complex situation in the drilling process through the drilling data; normalizing logging data, calculating various elastic parameters by using the processed logging data, establishing an intersection chart by using an elastic parameter result, selecting sensitive elastic parameters capable of reflecting lithology by combining logging data, and constructing a lithology prediction template based on geophysical elastic parameters; and obtaining regional geophysical elastic parameters by using seismic inversion software, sequentially identifying and stripping corresponding lithology according to a lithology prediction template plate based on the geophysical elastic parameters, and establishing an overall lithology prediction section.
Example 1: pre-drilling lithology prediction method
The embodiment 1 of the invention provides a pre-drilling lithology prediction method, which comprises the following steps of:
step A: collecting operation data of a drilled well of an oil field in a target area, wherein the operation data comprise drilling data, logging data and logging data;
specifically, target zone H oilfield drilled well operation data is collected.
And (B) step (B): and counting the types and the quantity of the complex situations of the well drilled in the oil field in the target area according to the well drilling data, summarizing the statistics results of the duty ratio of the types of the complex situations of the well drilled in the oil field in the target area, and determining the main types of the complex situations of the well drilled in the oil field in the target area.
The complex situation types of the oil field in the target area comprise tripping resistance, low drilling speed and other three types, and the other complex types specifically comprise leakage, block dropping, torque holding, pump holding and the like.
The main types of methods for determining the complexity of a field of interest in which a well has been drilled are: the complex type with a sum of the ratios exceeding 80% is determined to be the main type of complex situation in which the oil field has been drilled in the target area.
Specifically, statistics is carried out on information such as the type, the number and the like of the complex situations of the drilled well of the H oil field, and the statistics results are summarized, so that the complex situation types of the drilled well of the H oil field are found to comprise: the drilling rate is 58 percent, the drilling speed is 27 percent and the other drilling rates are 15 percent, so that the types of complex situations of the oil field drilled in the target area with the total of the proportion exceeding 80 percent are determined as the former two, and the method is also the target of the next step to be studied.
Step C: the logging data is standardized, standardized logging data is constructed, and the method specifically comprises the following steps:
step C1: and establishing a frequency distribution diagram of the well logging data of the exploratory well according to the well logging data, and checking and confirming whether all the well logging data of the exploratory well meet the unified standard.
Specifically, the logging data includes formation natural gamma G R Formation density ρ, longitudinal wave time difference T A Time difference of transverse wave T S 。
Step C2: formation natural gamma G with nonstandard logging data caused by different logging ages and instruments R Formation density ρ, longitudinal wave time difference T A Time difference of transverse wave T S Carrying out standardized correction and forming standardized logging data together with other logging data meeting unified standards, wherein the standardized logging data comprises the following steps of:
step C21: formation natural gamma G R Is standardized by (a)
Because logging time and instruments are different, logging data are not standard, and standardized correction is needed. Checking and confirming whether the logging data of each exploratory well meets the unified standard. Specifically, according to the stratum natural gamma G of each exploratory well of the H oil field R Establishing formation natural gamma G from logging data of formation density ρ R And a profile of the occurrence frequency of the formation density ρ. Thus, formation natural gamma G R The standardization of (c) specifically comprises the following steps:
firstly, selecting a well which is the latest in logging time and most common in logging instruments in a drilled well in a target area as a reference well, and determining a stratum natural gamma value G with the highest occurrence frequency of the reference well R (reference);
secondly, according to the stratum natural gamma value G with the highest occurrence frequency of the reference well R (benchmark) determining the difference ΔG of the natural gamma values of the stratum with the highest occurrence frequency between the i well and the reference well R (i) The expression is；
ΔG R (i)＝G R (i)-G R (reference) (1)
In the formula, deltaG R (i) The difference value of the natural gamma value of the stratum with the highest occurrence frequency between the i well and the reference well is obtained;
G R the (reference) is the stratum natural gamma value with the highest occurrence frequency of the reference well;
G R (i) The natural gamma value of the stratum with the highest occurrence frequency of the i well is obtained;
finally, according to the difference delta G of the natural gamma values of the stratum with the highest occurrence frequency between the i well and the reference well R (i) Correcting all stratum natural gamma of the i well, wherein the correction formula is as follows:
G' R (i,j)＝G R (i,j)-ΔG R (i) (2)
in the formula, G' R (i, j) is the corrected natural gamma value of the j-th formation of the i-well;
G R (i, j) is the natural gamma value of the j-th stratum of the i-well before correction;
ΔG R (i) Is the difference in natural gamma value of the formation with the highest frequency of occurrence between the i-well and the reference well.
The following description will take 5-well as an example.
Specifically, G is the most current logging time and most common logging instrument for wells in a drilled well in this region R Logging median = 135,5 natural gamma G for formation with highest frequency of occurrence R (5) =125. Difference delta G of stratum natural gamma value with highest occurrence frequency between 5 wells and reference well R (5)＝125-135＝-10。
Correcting the natural gamma value G of the jth stratum of the 5 th well R (5,j) subtracting the difference DeltaG in the formation natural gamma value with the highest occurrence frequency between the 5 well and the reference well R (5) Obtaining the natural gamma value G 'of the jth stratum of the corrected 5-well' R (5,j)。
Through the treatment, 5 well G is eliminated R G to other wells due to errors in log values caused by age and logging tool differences R The log values are also processed in sequence. For the purpose of other well logging items,such as density logging, longitudinal wave time difference, transverse wave time difference, etc., are also processed sequentially.
Step C22: normalization of formation density ρ
Normalization of formation density ρ is in accordance with formation natural gamma G R The standardized method comprises the following steps:
firstly, selecting a well which is the latest in logging time and most common in logging instruments in a drilled well in a target area as a reference well, and determining stratum density rho (reference) with the highest occurrence frequency of the reference well;
secondly, according to the stratum density rho (reference) with the highest occurrence frequency of the reference well and the stratum density rho (i) with the highest occurrence frequency of the i well, obtaining a difference value Deltarho (i) of the stratum density with the highest occurrence frequency between the i well and the reference well, wherein the expression is as follows;
Δρ (i) =ρ (i) - ρ (reference) (3)
Where Δρ (i) is the difference in formation density between the i-well and the reference well with the highest frequency of occurrence;
ρ (reference) is the natural gamma value of the stratum with the highest occurrence frequency of the reference well;
ρ (i) is the formation density where the i-well occurs most frequently.
Finally, correcting all stratum densities of the i well according to a difference Deltaρ (i) of stratum densities with the highest occurrence frequency between the i well and the reference well, wherein a correction formula is as follows:
ρ'(i,j)＝ρ(i,j)-Δρ(i) (4)
wherein ρ' (i, j) is the corrected i-well jth formation density;
ρ (i, j) is the j-th formation density of the i-well prior to correction;
Δρ (i) is the difference in formation density between the i well and the reference well where the frequency is greatest.
Step C23: time difference of longitudinal wave T A Is standardized by (a)
Time difference of longitudinal wave T A Is normalized to the natural gamma G of the formation R The standardized method comprises the following steps:
first, the last logging time in a drilled well for a selected target zoneAnd the most common well of the logging instrument is used as a reference well, and the longitudinal wave time difference T with the highest occurrence frequency of the reference well is determined A (reference);
secondly, according to the longitudinal wave time difference T with the highest occurrence frequency of the reference well A Longitudinal wave time difference T with the highest occurrence frequency of (reference) and i-well A (reference) determining the difference DeltaT of the longitudinal wave time difference with the highest occurrence frequency between the i-well and the reference well A (i) The expression is as follows;
ΔT A (i)＝T A (i)-T A (reference) (5)
In the formula DeltaT A (i) The difference value of the longitudinal wave time difference with the highest occurrence frequency between the i well and the reference well is obtained;
T A the (reference) is the longitudinal wave time difference value with the highest occurrence frequency of the reference well;
T A (i) The longitudinal wave time difference with the highest occurrence frequency of the i well is obtained;
finally, according to the difference value delta T of the longitudinal wave time difference with the highest occurrence frequency between the i well and the reference well A (i) Correcting all longitudinal wave time differences of the i well, wherein the correction formula is as follows:
T' A (i,j)＝T A (i,j)-ΔT A (i) (6)
wherein T' A (i, j) is the j-th longitudinal wave time difference of the corrected i-well;
T A (i, j) is the j-th longitudinal wave time difference of the i-well before correction;
ΔT A (i) The difference between the longitudinal wave time differences with the highest occurrence frequency between the i well and the reference well.
Step C24: time difference T of transverse wave S Is standardized by (a)
Time difference T of transverse wave S Is normalized to the natural gamma G of the formation R The standardized method comprises the following steps:
first, a well with the latest logging time and the most common logging instrument in a drilled well in a target area is selected as a reference well, and a transverse wave time difference T with the most frequency of occurrence of the reference well is determined S (reference);
second, according to the transverse wave time difference with the highest occurrence frequency of the reference wellT S Transverse wave time difference T with highest frequency of occurrence of (reference) and i-well S (reference) determining the difference DeltaT of the transverse wave time difference with the highest occurrence frequency between the i-well and the reference well S (i) The expression is as follows;
ΔT S (i)＝T S (i)-T S (reference) (7)
In the formula DeltaT S (i) The difference value of the transverse wave time difference with the highest occurrence frequency between the i well and the reference well is obtained;
T S the (reference) is the transverse wave time difference value with the highest occurrence frequency of the reference well;
T S (i) The transverse wave time difference with the highest occurrence frequency of the i well is the same as that of the i well;
finally, according to the difference value delta T of transverse wave time difference with the highest occurrence frequency between the i well and the reference well S (i) Correcting all transverse wave time differences of the i well, wherein the correction formula is as follows:
T' S (i,j)＝T S (i,j)-ΔT S (i) (8)
wherein T' S (i, j) is the corrected j-th transverse wave time difference of the i-well;
T S (i, j) is the j-th shear wave time difference of the i-well before correction;
ΔT S (i) Is the difference in transverse wave time difference between the i well and the reference well with the highest occurrence frequency.
Step D: and comparing the formation with lithology of the formation where the complex situation occurs according to the logging information, the main type and the duty ratio of the complex situation of the oil field in the target area, and the standardized logging data.
The lithology of the complex situation includes, among other things, igneous rock formations and sedimentary rock formations. Specifically, the stratum where the drilling speed of the H oilfield drilling is low is mainly a igneous rock stratum such as granite, basalt, amphibole, breccia, tuff and the like, and the stratum is generally hard in property and poor in drillability. The H field drilling is started and the blocking occurs, and 85% of the blocking occurs at the interface between different lithologies of the sedimentary rock stratum.
Lithology of complex situations includes igneous, coarse, limestone, calcareous fine, mudstone, fine and medium sandstone in addition to igneous and sedimentary rock formations.
Step E: obtaining geophysical elasticity parameters of the stratum of the well drilled in the target area according to the standardized logging data; reading stratum lithology according to the well logging data of the well drilling, drawing an elastic parameter intersection diagram of the whole drilling depth, respectively selecting one or two sensitive elastic parameters capable of reflecting lithology from geophysical elastic parameters of the stratum of the well drilling of the target area according to the elastic parameter intersection diagram of the whole drilling depth, and identifying and stripping igneous rock, coarse sandstone, limestone, calcareous fine sandstone, mudstone, fine sandstone and medium sandstone one by one, so as to establish a lithology prediction template based on the geophysical elastic parameters, wherein the lithology prediction template comprises the following steps:
step E1: obtaining geophysical elastic parameters of a formation drilled in the target area according to the standardized logging data, wherein the geophysical elastic parameters comprise standardized formation density rho ', standardized formation natural gamma G' R Normalized longitudinal wave time difference T' A Normalized transverse wave time difference T' S Impedance I of transverse wave S Impedance of longitudinal wave I A Poisson's ratio v, elastic wave impedance I G Mei Jishu L and pull Mei Jishu L ambda The method specifically comprises the following steps:
firstly, normalized formation density rho ' and normalized formation natural gamma G ' are obtained ' R Normalized longitudinal wave time difference T' A Normalized transverse wave time difference T' S ；
Then, based on the normalized formation density ρ ', the normalized formation natural gamma G' R Normalized longitudinal wave time difference T' A Normalized transverse wave time difference T' S Calculating geophysical elastic parameters of a formation in a target zone that has been drilled, including transverse wave impedance I S Impedance of longitudinal wave I A Poisson's ratio v, elastic wave impedance I G Mei Jishu L and pull Mei Jishu L ambda The calculation formula is as follows:
wherein ρ' is the normalized formation density; t'. A The time difference of the longitudinal wave is normalized; t'. S The time difference is the normalized transverse wave time difference; i S Is transversal wave impedance; i A Is the longitudinal wave impedance; v is poisson's ratio; k is an intermediate value; g I Is elastic wave impedance;the minimum value of the normalized longitudinal wave time difference; />Is the minimum value of the normalized transverse wave time difference; ρ' min Is the minimum value of the normalized formation density; i A Is the longitudinal wave impedance; i S Is transversal wave impedance; l (L) ambda Is pull Mei Jishu.
Note that ρ 'in formula 9 is equal to ρ' (i, j) in formula 4, T 'in formula 9' A Equal to T 'in formula 6' A (i, j) T 'in formula 9' S Equal to T 'in formula 6' S (i,j)。
Step E2: reading stratum lithology according to the well logging data of the well to be drilled, and drawing an elastic parameter intersection chart of the whole drilling depth; respectively selecting one or two sensitive elastic parameters capable of reflecting lithology from geophysical elastic parameters of a stratum drilled in the target area according to the elastic parameter intersection map of the whole drilling depth, and identifying and stripping igneous rock, coarse sandstone, limestone, calcareous fine sandstone, mudstone, fine sandstone and medium sandstone one by one to establish a lithology prediction template based on the geophysical elastic parameters, wherein the lithology prediction template comprises the following steps of:
step E21: reading stratum lithology according to the well logging data of the well, wherein each lithology is represented by one color to draw an elastic parameter intersection chart of a certain depth point, and drawing the elastic parameter intersection chart of the whole well drilling depth according to different depth points as shown in figure 1;
step E22: respectively selecting one or two sensitive elastic parameters capable of reflecting lithology from geophysical elastic parameters of a stratum drilled in the target area according to the elastic parameter intersection map of the whole drilling depth, and identifying and stripping igneous rock, coarse sandstone, limestone fine sandstone, mudstone, fine sandstone and medium sandstone one by one, wherein the specific steps are as follows:
Step 1: referring to FIG. 1 (a), the impedance I is first determined based on the longitudinal wave A >11000g/cm 3 M/s and transverse wave impedance I S >6000g/cm 3 M/s identifying and stripping out igneous rock formations including granite, basalt, amphibole, breccia, tuff;
step 2: in the remaining formations other than the igneous rock formation, referring to fig. 1 (b), coarse sandstone is identified and stripped according to poisson's ratio v < 0.23;
step 3: in the remaining formation, referring to FIG. 1 (c), according to 8500g/cm 3 ·m/s<Elastic wave impedance G I <9500g/cm 3 M/s identifying and stripping off limestone;
step 4: in the remaining formation, referring to FIG. 1 (d), according to Law Mei Jishu L ambda >Identifying and stripping out calcareous fine sandstone by 25 GPa;
step 5: in the remaining formation, referring to FIG. 1 (e), according to the formation density ρ>2.53g/cm 3 Identifying and stripping out mudstone;
step 6: in the remaining formation, referring to FIG. 1 (f), according to the longitudinal wave impedance I A >11000g/cm 3 M/s identification and stripping of fine sandstone;
step 7: the last remaining is medium sandstone.
In step 7, the fine sandstone and the medium sandstone are close to each other, so that the discrimination between the fine sandstone and the medium sandstone is not as high as that between other lithologies.
Step F: and obtaining a geophysical elastic parameter profile of the target area without drilling by utilizing seismic inversion, establishing a lithology prediction profile of the target area without drilling by setting a quantitative threshold according to the lithology prediction template based on the geophysical elastic parameter, and carrying out lithology prediction of the target area without drilling.
Wherein the geophysical elastic parameters can be obtained by inversion of pre-drilling seismic data,obtaining geophysical elastic parameters of a target area, namely longitudinal wave impedance I, by using seismic inversion software A Impedance I of transverse wave S Poisson's ratio v, elastic wave impedance G I Mei Jishu L and pull Mei Jishu L ambda And the formation density rho, and sequentially identifying and stripping the corresponding lithology, namely igneous rock, coarse sandstone, limestone, calcareous fine sandstone, mudstone, fine sandstone and medium sandstone according to 7 steps in the prediction template, and finally establishing an integral lithology prediction section, as shown in figure 2.
The lithology prediction template based on the geophysical elastic parameters is lithology recognition realized by setting quantitative threshold values, and each geophysical elastic parameter respectively meets the threshold value conditions to divide lithology.
The pre-drilling lithology prediction method disclosed by the invention comprehensively utilizes the drilling data, logging data and regional seismic data of the exploratory well, rather than only utilizing the logging lithology data of the exploratory well. The method disclosed by the invention focuses on a plurality of lithologies, but not all lithologies, which are mainly complicated, and provides risk early warning for future drilling.
Example 2: lithology prediction device under complex condition before oilfield drilling
Embodiment 2 of the present invention provides a lithology prediction apparatus for complex conditions before drilling in an oilfield, including
The first processing unit is used for collecting operation data of drilled wells of the oil field in the target area, including drilling data, logging data and logging data;
the second processing unit is used for counting the types and the quantity of the complex situations of the well drilled in the oil field in the target area according to the well drilling data, summarizing the statistics results of the duty ratio of the types of the complex situations of the well drilled in the oil field in the target area, and determining the main types of the complex situations of the well drilled in the oil field in the target area;
the third processing unit is used for carrying out standardization processing on the logging data and constructing standardized logging data;
the fourth processing unit is used for comparing the formation of the uncomplicated situation with the lithology of the formation where the complex situation occurs according to the logging information, the main type and the duty ratio of the complex situation of the oil field in the target area, and the standardized logging data;
a fifth processing unit, configured to obtain a geophysical elastic parameter of a formation in which the target area has been drilled according to the normalized logging data; reading stratum lithology according to the well logging data of the well drilling, drawing an elastic parameter intersection diagram of the whole drilling depth, respectively selecting one or two sensitive elastic parameters capable of reflecting lithology from geophysical elastic parameters of the stratum of the well drilling of the target area according to the elastic parameter intersection diagram of the whole drilling depth, identifying and stripping igneous rock, coarse sandstone, limestone, calcareous fine sandstone, mudstone, fine sandstone and medium sandstone one by one, and establishing a lithology prediction template based on the geophysical elastic parameters.
Example 3: computer readable storage medium
Embodiment 3 of the present invention provides a computer-readable storage medium having stored thereon a computer program, characterized in that the computer program when executed by a processor realizes the steps of the method described in embodiment 1.
Example 4: computer equipment
Embodiment 4 of the present invention provides a computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the steps of the method described in embodiment 1 when executing the computer program.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims (10)
1. A method of pre-drilling lithology prediction, comprising:
Collecting operation data of a drilled well of an oil field in a target area, wherein the operation data comprise drilling data, logging data and logging data;
counting the types and the quantity of the complex situations of the well drilled in the oil field of the target area according to the well drilling data, summarizing the statistics results of the duty ratio of the types of the complex situations of the well drilled in the oil field of the target area, and determining the main types of the complex situations of the well drilled in the oil field of the target area;
carrying out standardization processing on the logging data to construct standardized logging data;
determining lithology of the stratum where the complex situation occurs by comparing the stratum where the complex situation occurs with lithology of the stratum where the complex situation occurs according to the logging data, the main type and the duty ratio of the complex situation of the oil field drilled in the target area and the standardized logging data;
obtaining geophysical elasticity parameters of the stratum of the well drilled in the target area according to the standardized logging data; reading stratum lithology according to the well logging data of the well drilling, drawing an elastic parameter intersection diagram of the whole drilling depth, respectively selecting one or two sensitive elastic parameters capable of reflecting lithology from geophysical elastic parameters of the stratum of the well drilling of the target area according to the elastic parameter intersection diagram of the whole drilling depth, identifying and stripping igneous rock, coarse sandstone, limestone, calcareous fine sandstone, mudstone, fine sandstone and medium sandstone one by one, and establishing a lithology prediction template based on the geophysical elastic parameters.
2. The pre-drilling lithology prediction method according to claim 1, wherein the construction of the normalized logging data specifically comprises the steps of:
establishing a frequency distribution diagram of the well logging data of the exploratory well according to the well logging data, and checking and confirming whether all the well logging data of the exploratory well meet the unified standard;
formation natural gamma G with nonstandard logging data caused by different logging ages and instruments R Formation density ρ, verticalTime difference of wave T A Time difference of transverse wave T S And carrying out standardized correction, and constructing standardized logging data together with other logging data meeting unified standards.
3. The method of pre-drilling lithology prediction according to claim 2, wherein,
natural gamma G of the stratum R The standardization of (c) specifically comprises the following steps:
firstly, selecting a well which is the latest in logging time and most common in logging instruments in a drilled well in a target area as a reference well, and determining a stratum natural gamma value G with the highest occurrence frequency of the reference well R (reference);
secondly, according to the stratum natural gamma value G with the highest occurrence frequency of the reference well R (benchmark) determining the difference ΔG of the natural gamma values of the stratum with the highest occurrence frequency between the i well and the reference well R (i) The expression is as follows;
ΔG R (i)＝G R (i)-G R (reference) (1)
In the formula, deltaG R (i) The difference value of the natural gamma value of the stratum with the highest occurrence frequency between the i well and the reference well is obtained;
G R the (reference) is the stratum natural gamma value with the highest occurrence frequency of the reference well;
G R (i) The natural gamma value of the stratum with the highest occurrence frequency of the i well is obtained;
finally, according to the difference delta G of the natural gamma values of the stratum with the highest occurrence frequency between the i well and the reference well R (i) Correcting all stratum natural gamma of the i well, wherein the correction formula is as follows:
G' R (i,j)＝G R (i,j)-ΔG R (i) (2)
in the formula, G' R (i, j) is the corrected natural gamma value of the j-th formation of the i-well;
G R (i, j) is the natural gamma value of the j-th stratum of the i-well before correction;
ΔG R (i) Is the difference in natural gamma value of the formation with the highest frequency of occurrence between the i-well and the reference well.
4. The method for predicting pre-drilling lithology according to claim 3, wherein,
the standardization of the formation density rho specifically comprises the following steps:
firstly, selecting a well which is the latest in logging time and most common in logging instruments in a drilled well in a target area as a reference well, and determining stratum density rho (reference) with the highest occurrence frequency of the reference well;
secondly, according to the stratum density rho (reference) with the highest occurrence frequency of the reference well and the stratum density rho (i) with the highest occurrence frequency of the i well, obtaining a difference value Deltarho (i) of the stratum density with the highest occurrence frequency between the i well and the reference well, wherein the expression is as follows;
Δρ (i) =ρ (i) - ρ (reference) (3)
Where Δρ (i) is the difference in formation density between the i-well and the reference well with the highest frequency of occurrence;
ρ (reference) is the natural gamma value of the stratum with the highest occurrence frequency of the reference well;
ρ (i) is the formation density with the highest occurrence frequency of the i-well;
finally, correcting all stratum densities of the i well according to a difference Deltaρ (i) of stratum densities with the highest occurrence frequency between the i well and the reference well, wherein a correction formula is as follows:
ρ'(i,j)＝ρ(i,j)-Δρ(i) (4)
wherein ρ' (i, j) is the corrected i-well jth formation density;
ρ (i, j) is the j-th formation density of the i-well prior to correction;
Δρ (i) is the difference in formation density between the i well and the reference well where the frequency is greatest.
5. The method of pre-drilling lithology prediction according to claim 4,
the longitudinal wave time difference T A The standardization of (c) specifically comprises the following steps:
first, a well with the latest logging time and the most common logging instrument in a drilled well in a target area is selected as a reference well, and a determination is madeLongitudinal wave time difference T with maximum occurrence frequency of reference well A (reference);
secondly, according to the longitudinal wave time difference T with the highest occurrence frequency of the reference well A Longitudinal wave time difference T with the highest occurrence frequency of (reference) and i-well A (reference) determining the difference DeltaT of the longitudinal wave time difference with the highest occurrence frequency between the i-well and the reference well A (i) The expression is as follows;
ΔT A (i)＝T A (i)-T A (reference) (5)
In the formula DeltaT A (i) The difference value of the longitudinal wave time difference with the highest occurrence frequency between the i well and the reference well is obtained;
T A the (reference) is the longitudinal wave time difference value with the highest occurrence frequency of the reference well;
T A (i) The longitudinal wave time difference with the highest occurrence frequency of the i well is obtained;
finally, according to the difference value delta T of the longitudinal wave time difference with the highest occurrence frequency between the i well and the reference well A (i) Correcting all longitudinal wave time differences of the i well, wherein the correction formula is as follows:
T' A (i,j)＝T A (i,j)-ΔT A (i) (6)
wherein T' A (i, j) is the j-th longitudinal wave time difference of the corrected i-well;
T A (i, j) is the j-th longitudinal wave time difference of the i-well before correction;
ΔT A (i) The difference between the longitudinal wave time differences with the highest occurrence frequency between the i well and the reference well.
6. The method of pre-drilling lithology prediction according to claim 5,
the transverse wave time difference T S The standardization of (c) specifically comprises the following steps:
first, a well with the latest logging time and the most common logging instrument in a drilled well in a target area is selected as a reference well, and a transverse wave time difference T with the most frequency of occurrence of the reference well is determined S (reference);
second, according to the transverse wave time difference T with the highest occurrence frequency of the reference well S (reference) and i-well transverse waves with the highest occurrence frequencyTime difference T S (reference) determining the difference DeltaT of the transverse wave time difference with the highest occurrence frequency between the i-well and the reference well S (i) The expression is as follows;
ΔT S (i)＝T S (i)-T S (reference) (7)
In the formula DeltaT S (i) The difference value of the transverse wave time difference with the highest occurrence frequency between the i well and the reference well is obtained;
T S the (reference) is the transverse wave time difference value with the highest occurrence frequency of the reference well;
T S (i) The transverse wave time difference with the highest occurrence frequency of the i well is the same as that of the i well;
finally, according to the difference value delta T of transverse wave time difference with the highest occurrence frequency between the i well and the reference well S (i) Correcting all transverse wave time differences of the i well, wherein the correction formula is as follows:
T' S (i,j)＝T S (i,j)-ΔT S (i) (8)
wherein T' S (i, j) is the corrected j-th transverse wave time difference of the i-well;
T S (i, j) is the j-th shear wave time difference of the i-well before correction;
ΔT S (i) Is the difference in transverse wave time difference between the i well and the reference well with the highest occurrence frequency.
7. The pre-drilling lithology prediction method of claim 6, wherein obtaining the geophysical elastic parameters of the formation in which the target zone has been drilled from the normalized well log data comprises:
firstly, normalized formation density rho ' and normalized formation natural gamma G ' are obtained ' R Normalized longitudinal wave time difference T' A Normalized transverse wave time difference T' S ；
Then, based on the normalized formation density ρ ', the normalized formation natural gamma G' R Normalized longitudinal wave time difference T' A Normalized transverse wave time difference T' S Calculating geophysical elastic parameters of a formation in a target zone that has been drilled, including transverse wave impedance I S Longitudinal wave resistanceanti-I A Poisson's ratio v, elastic wave impedance I G Mei Jishu L and pull Mei Jishu L ambda The calculation formula is as follows:
wherein ρ' is the normalized formation density; t'. A The time difference of the longitudinal wave is normalized; t'. S The time difference is the normalized transverse wave time difference; i S Is transversal wave impedance; i A Is the longitudinal wave impedance; v is poisson's ratio; k is an intermediate value; g I Is elastic wave impedance;the minimum value of the normalized longitudinal wave time difference; />Is the minimum value of the normalized transverse wave time difference; ρ' min Is the minimum value of the normalized formation density; i A Is the longitudinal wave impedance; i S Is transversal wave impedance; l (L) ambda Is pull Mei Jishu.
8. The pre-drilling lithology prediction method according to claim 7, wherein the step of identifying and stripping igneous rock, coarse sandstone, limestone, calcareous fine sandstone, mudstone, fine sandstone, and medium sandstone one by one specifically comprises the steps of:
first according to the longitudinal wave impedance I A >11000g/cm 3 M/s and transverse wave impedance I S >6000g/cm 3 M/s identifying and stripping out igneous rock formations including granite, basalt, amphibole, breccia, tuff;
identifying and stripping coarse sandstone in the remaining formations other than the igneous rock formation according to poisson ratio v < 0.23;
In the remaining formation, according to 8500g/cm 3 ·m/s<Elastic wave impedance G I <9500g/cm 3 M/s identifying and stripping off limestone;
in the remaining formation according to Law Mei Jishu L ambda >Identifying and stripping out calcareous fine sandstone by 25 GPa;
in the remaining formation, according to the formation density ρ>2.53g/cm 3 Identifying and stripping out mudstone;
in the remaining stratum, according to the longitudinal wave impedance I A >11000g/cm 3 M/s identification and stripping of fine sandstone;
the last remaining is medium sandstone.
9. The pre-drilling lithology prediction method of claim 1, further comprising the steps of:
and obtaining a geophysical elastic parameter profile of the target area without drilling by utilizing seismic inversion, establishing a lithology prediction profile of the target area without drilling by setting a quantitative threshold according to the lithology prediction template based on the geophysical elastic parameter, and carrying out lithology prediction of the target area without drilling.
10. A pre-drilling lithology prediction device, comprising
The first processing unit is used for collecting operation data of drilled wells of the oil field in the target area, including drilling data, logging data and logging data;
the second processing unit is used for counting the types and the quantity of the complex situations of the well drilled in the oil field in the target area according to the well drilling data, summarizing the statistics results of the duty ratio of the types of the complex situations of the well drilled in the oil field in the target area, and determining the main types of the complex situations of the well drilled in the oil field in the target area;
The third processing unit is used for carrying out standardization processing on the logging data and constructing standardized logging data;
the fourth processing unit is used for comparing the formation of the uncomplicated situation with the lithology of the formation where the complex situation occurs according to the logging information, the main type and the duty ratio of the complex situation of the oil field in the target area, and the standardized logging data;
a fifth processing unit, configured to obtain a geophysical elastic parameter of a formation in which the target area has been drilled according to the normalized logging data; reading stratum lithology according to the well logging data of the well drilling, drawing an elastic parameter intersection diagram of the whole drilling depth, respectively selecting one or two sensitive elastic parameters capable of reflecting lithology from geophysical elastic parameters of the stratum of the well drilling of the target area according to the elastic parameter intersection diagram of the whole drilling depth, identifying and stripping igneous rock, coarse sandstone, limestone, calcareous fine sandstone, mudstone, fine sandstone and medium sandstone one by one, and establishing a lithology prediction template based on the geophysical elastic parameters.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311093158.3A CN117172361A (en) | 2023-08-28 | 2023-08-28 | Pre-drilling lithology prediction method and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311093158.3A CN117172361A (en) | 2023-08-28 | 2023-08-28 | Pre-drilling lithology prediction method and system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117172361A true CN117172361A (en) | 2023-12-05 |
Family
ID=88935006
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311093158.3A Pending CN117172361A (en) | 2023-08-28 | 2023-08-28 | Pre-drilling lithology prediction method and system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117172361A (en) |
-
2023
- 2023-08-28 CN CN202311093158.3A patent/CN117172361A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110397402B (en) | Drilling method and device | |
| US11230922B2 (en) | Fracture interpretation with resistivity and sonic logs in biaxial anisotropic formations | |
| US9176255B2 (en) | Permeability prediction systems and methods using quadratic discriminant analysis | |
| CN104948176B (en) | A kind of method based on infiltration Magnification identification carbonate reservoir crack | |
| CN109870720B (en) | Shale gas micro-crack well logging identification method | |
| US11892581B2 (en) | Methods and systems for characterizing clay content of a geological formation | |
| CN113419284B (en) | Method for identifying physical facies double desserts of well logging rock based on cluster analysis | |
| CN111767674A (en) | Well logging lithology identification method based on active domain adaptation | |
| EP2616978A1 (en) | System and method for sweet zone identification in shale gas reservoirs | |
| CN107831540A (en) | The direct new method for extracting of reservoir physical parameter | |
| US10073182B2 (en) | Combination model for predicting stiffness coefficients absent Stoneley wave velocity data | |
| CN109425912A (en) | A kind of recognition methods of Carbonate Reservoir reservoir effective fracture | |
| CN110939428B (en) | Identification method for tight sandstone oil and gas reservoir cracks | |
| WO2018156672A1 (en) | Systems and methods for monitoring casing cement integrity | |
| CN113189672B (en) | Tunnel advance geological forecast method based on multi-attribute inversion | |
| CN109826623B (en) | Geophysical well logging identification method for tight sandstone reservoir bedding joints | |
| CN117172361A (en) | Pre-drilling lithology prediction method and system | |
| CN110603370B (en) | Determining formation content | |
| US10677959B2 (en) | Method of and apparatus for calculating UCS and CCS | |
| CN112630839B (en) | Logging curve standardization method and system | |
| WO2021252643A1 (en) | Geomechanical applications using biot's coefficient based on advanced downhole logging measurements | |
| CN112394416A (en) | Heterogeneous fracture control reservoir prediction method and device | |
| US10013748B2 (en) | Downhole imaging techniques using lamination analysis | |
| CN110346416A (en) | The method of characteristic parameter Curves Recognition Volcanic uranium deposit based on sound wave and resistivity | |
| US20230313665A1 (en) | Detection of potential geological control points with logging-while-drilling sensors |
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 |