CN111894567A - Water saturation measuring method suitable for tight sandstone reservoir - Google Patents
Water saturation measuring method suitable for tight sandstone reservoir Download PDFInfo
- Publication number
- CN111894567A CN111894567A CN202010774361.7A CN202010774361A CN111894567A CN 111894567 A CN111894567 A CN 111894567A CN 202010774361 A CN202010774361 A CN 202010774361A CN 111894567 A CN111894567 A CN 111894567A
- Authority
- CN
- China
- Prior art keywords
- reservoir
- dimension
- log
- correlation
- index
- 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
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 42
- 238000002474 experimental method Methods 0.000 claims abstract description 16
- 239000011435 rock Substances 0.000 claims description 10
- 230000005611 electricity Effects 0.000 claims description 5
- 239000008398 formation water Substances 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 10
- 238000004364 calculation method Methods 0.000 description 7
- 238000004590 computer program Methods 0.000 description 7
- 230000006870 function Effects 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 238000011156 evaluation Methods 0.000 description 2
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 2
- 229910052753 mercury Inorganic materials 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000002734 clay mineral Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007717 exclusion Effects 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geophysics And Detection Of Objects (AREA)
Abstract
The invention discloses a method for measuring water saturation of a tight sandstone reservoir, which comprises the following steps: obtaining well logs of multiple categories of each reservoir through known rock-electricity experiments of cores of multiple reservoirs; calculating the correlation dimension of the log of each category of each reservoir; solving a first fractal dimension and a second fractal dimension of each reservoir, establishing a first linear relation between the first fractal dimension of each reservoir and the cementation index of the reservoir by adopting a linear fitting method, and establishing a second linear relation between the second fractal dimension of each reservoir and the saturation index of the reservoir; establishing a linear relation between the cementation index of each reservoir and the loga, and dividing the well to be tested into a plurality of reservoirs; calculating the cementation index and the saturation index of each reservoir stratum to be logged; and calculating the water saturation of each reservoir to be logged. The measuring method can accurately measure the water saturation of the tight sandstone reservoir.
Description
Technical Field
The invention relates to the field of well logging interpretation, in particular to a method for measuring water saturation of a tight sandstone reservoir.
Background
In the evaluation of water saturation in the field of well logging interpretation, a common method at present is to calculate the value of water saturation using the Archie's formula. The cementation index m and the saturation index n in the Archie formula are generally fixed m and n values obtained by using a certain well rock electrical experiment.
The inventor finds that for a compact sandstone reservoir, the lithologic property is compact, the pore space is small, the throat is thin, the connectivity is poor, the heterogeneity is strong, the formation heterogeneity is strong, cracks develop, the pore structure is complex, mineral components such as clay minerals and chloride are complex, the cracks in the reservoir develop widely, the cementation index (m) and the saturation index (n) of the reservoir deviate from empirical values, the error of the values of m and n obtained by the existing rock electricity utilization experiment is large, and the value of the water saturation obtained by substituting the values into the Archie formula also has large errors.
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
The invention aims to provide a method for measuring the water saturation of a tight sandstone reservoir, which can accurately measure the water saturation of the tight sandstone reservoir.
In order to achieve the aim, the invention provides a method for measuring the water saturation of a tight sandstone reservoir, which comprises the following steps: obtaining well logs of multiple categories of each reservoir through known rock-electricity experiments of cores of multiple reservoirs; calculating the correlation dimension of the log of each category of each reservoir; obtaining a first fractal dimension and a second fractal dimension of each reservoir according to the correlation dimension of the logging curve of each reservoir, wherein the first fractal dimension of each reservoir is related to the cementation index of the reservoir, and the second fractal dimension of each reservoir is related to the saturation index of the reservoir; establishing a first linear relation between the first fractal dimension of each reservoir and the cementation index of the reservoir by adopting a linear fitting method, and establishing a second linear relation between the second fractal dimension of each reservoir and the saturation index of the reservoir; establishing a linear relation between the cementation index of each reservoir and the loga according to the rock electricity experiments of the rock cores of the reservoirs, wherein a is a parameter in an Archie formula; dividing a well to be tested into a plurality of reservoirs; calculating the cementation index and the saturation index of each reservoir to be logged according to the first linear relational expression and the second linear relational expression; and calculating the water saturation of each reservoir to be logged based on the Archie's formula.
In one embodiment of the present invention, the plurality of categories of well logs comprise: acoustic time difference log, compensated neutron log, compensated density log, and resistivity log.
In one embodiment of the present invention, calculating the correlation dimension for each category of well log for each reservoir comprises: for a well log, first, time series X is used1,X2,...,XNGiven an initial value m of the embedding dimension0Reconstructing the phase space to obtain a new sequence { Yi }, wherein X1,X2,...,XNA spherical box with a radius r and taking Br (Xi) as a center as a point on the attractor in a phase space as a reference point Xi; determining distances r for all point pairs in the new sequenceijAnd distances r of all point pairsijIs compared with r to determine rijA number of point pairs less than r; calculating a correlation integral C (r), wherein the correlation integral C (r) is rijThe proportion of the point pairs smaller than r in all the point pairs; obtaining the corresponding m by least square fitting0Estimated value of the correlation dimension d (m)0) (ii) a Increase m0According to the above steps, re-calculating the correlation dimension estimate d (m)0) Up to the estimated value of the correlation dimension d (m)0) Is maintained within a preset range, and m is recorded0A final value of; according to said m0And (3) making an intersection graph of LnC (r) -Lnr, selecting a section with linearity larger than a certain value for linear fitting, and calculating a slope value of a fitting straight line, wherein the slope value is the correlation dimension of the logging curve.
In one embodiment of the invention, deriving the first fractal dimension and the second fractal dimension based on the correlation dimension of the well logs for each reservoir comprises: determining the first fractal dimension D from a first patternmWhich isIn the first formula Dm＝[(Dcnl+Dden)+2*Dac]/4 wherein DcnlFor the correlation dimension, D, of the compensated neutron logdenFor the correlation dimension, D, of the compensated density logacThe correlation dimension of the acoustic moveout log is taken as the correlation dimension of the acoustic moveout log; if D ism≥DrtDetermining said second fractal dimension D according to a second equationnOtherwise, determining the second fractal dimension D according to a third equationnWherein the second formula is Dn＝DmThe third formula is Dn＝DrtWherein D isrtIs the correlation dimension of the resistivity log.
In an embodiment of the present invention, the first linear relation is m ═ km*Dm+bmWherein m represents the cementation index, kmAnd bmAre all fitting coefficients.
In an embodiment of the present invention, the second linear relation is n ═ kn*Dn+bnWherein n represents the saturation index, knAnd bnAre all fitting coefficients.
In one embodiment of the present invention, the Archie's formula is
Wherein S iswFor water saturation, a and b are both lithology-related constants, RwIn order to be the formation water resistivity,
is porosity.
Compared with the prior art, the method for measuring the water saturation of the tight sandstone reservoir fully considers that the m and n values of each reservoir are not fixed due to the heterogeneity of the tight sandstone reservoir, constructs a dynamic m and n value shape solving method, further calculates the water saturation through an Archie formula, does not adopt a fixed value in the calculation of the water saturation, ensures that the calculation result is more accurate, and better accords with the actual stratum condition.
Drawings
FIG. 1 is a block diagram of the steps of a method for measuring water saturation according to an embodiment of the present invention;
FIG. 2 is a cross plot of correlation dimensions and cementation exponent according to an embodiment of the present invention;
FIG. 3 is a cross-plot of an association dimension and a saturation index, according to an embodiment of the present invention;
FIG. 4 is an explanatory diagram of well logging according to an embodiment of the present invention.
Detailed Description
The following detailed description of the present invention is provided in conjunction with the accompanying drawings, but it should be understood that the scope of the present invention is not limited to the specific embodiments.
Throughout the specification and claims, unless explicitly stated otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.
Fig. 1 is a method for measuring water saturation for tight sand reservoirs in accordance with an embodiment of the present invention. The method for measuring the water saturation comprises the following steps: steps S1 to S7.
The correlation dimension for each reservoir is calculated from the well logs in step S1.
Specifically, a plurality of types of well logs of each reservoir are obtained through a rock-electricity experiment of cores of a plurality of reservoirs known in a certain region, wherein the well logs comprise: acoustic time difference log, compensated neutron log, compensated density log, and resistivity log.
The correlation dimension of the well log of each category is then calculated.
For a given well log, the process of calculating the correlation dimension is as follows.
First using a time series X1,X2,...,XNGiven an initial value m of the embedding dimension0Reconstructing phase spaceIn between, a new sequence { Yi }, where X1,X2,...,XNA spherical box with a radius r and centered at a reference point Xi is represented by Br (Xi) as a point on the attractor in phase space.
Secondly determining the distances r of all point pairs in the new sequenceijAnd distances r of all point pairsijIs compared with r to determine rijThe number of pairs of points being smaller than r.
Secondly, calculating a correlation integral C (r), wherein the correlation integral C (r) is rijThe ratio of the point pairs smaller than r to all the point pairs.
Secondly, obtaining the corresponding m by adopting a least square fitting method0Estimated value of the correlation dimension d (m)0)。
Second increase m0According to the above steps, re-calculating the correlation dimension estimate d (m)0) Up to the estimated value of the correlation dimension d (m)0) Is maintained within a preset range, and m is recorded0The final value of (c).
Finally according to said m0And (3) making an intersection graph of LnC (r) -Lnr, selecting a section with linearity larger than a certain value for linear fitting, and calculating a slope value of a fitting straight line, wherein the slope value is the correlation dimension of the logging curve.
Sequentially determining the correlation dimension D of the compensated neutron logging curve according to the methodcnlThe correlation dimension D of the compensated density logdenThe correlation dimension D of the acoustic time difference logacAnd the correlation dimension D of the resistivity logrt。
A first fractal dimension and a second fractal dimension are determined in step S2. And solving a first fractal dimension and a second fractal dimension of each reservoir according to the correlation dimensions of the logging curves of all the categories of each reservoir, wherein the first fractal dimension of each reservoir is related to the cementation index of the reservoir, and the second fractal dimension of each reservoir is related to the saturation index of the reservoir.
In particular, the first score is determined from the first patternDimension of form DmWherein the first formula is Dm＝[(Dcnl+Dden)+2*Dac]/4 wherein DcnlFor the correlation dimension, D, of the compensated neutron logdenFor the correlation dimension, D, of the compensated density logacAnd the correlation dimension of the acoustic time difference logging curve is obtained.
If D ism≥DrtDetermining said second fractal dimension D according to a second equationnOtherwise, determining the second fractal dimension D according to a third equationnWherein the second formula is Dn＝DmThe third formula is Dn＝DrtWherein D isrtIs the correlation dimension of the resistivity log.
The first linear relationship and the second linear relationship are determined in step S3. And (3) making an intersection graph of the cementation index and the saturation index obtained by the rock-electricity experiment of each reservoir and the correlation dimension of the corresponding reservoir logging curve, establishing a first linear relation between the first fractal dimension of each reservoir and the cementation index of the reservoir by adopting a linear fitting method, and establishing a second linear relation between the second fractal dimension of each reservoir and the saturation index of the reservoir.
Wherein the first linear relation is m ═ km*Dm+bmWherein m represents the cementation index, kmAnd bmAre fitting coefficients. The second linear relation is n ═ kn*Dn+bnWherein n represents the saturation index, knAnd bnAre fitting coefficients.
And in step S4, establishing a linear relation between the cementation index and the loga of each reservoir according to the rock electricity experiments of the cores of the reservoirs, wherein a is a parameter related to water saturation, namely a parameter in an Archie formula.
In step S5, the well to be tested is divided into a plurality of reservoirs, wherein the geological structure of the reservoir to be tested is similar to that of the above-mentioned rock electricity experiment, and preferably the wells are in the same region, such as a basin and a garage area. In order to improve the accuracy of the water saturation calculation results, the thickness of each reservoir is approximately equal to the thickness of the reservoir used for linear fitting (rock electrical experiments) as much as possible when dividing the reservoirs.
And calculating a cementation exponent m and a saturation exponent n of each reservoir to be logged according to the first linear relation and the second linear relation in step S6.
In step S7, the water saturation of each reservoir to be logged is calculated by substituting m, n, a of each reservoir to be logged into the algi formula.
Wherein the Archie formula is
Wherein S iswFor water saturation, a and b are both lithology-related constants, RwIn order to be the formation water resistivity,
is porosity.
According to the embodiment, if the water saturation of a certain reservoir is required to be calculated, the cementation exponent (m) and the saturation exponent of the reservoir can be obtained through the first linear relation and the second linear relation. And substituting the calculated m and n values into an Archie formula to calculate the water saturation of the reservoir, so that when a well is subjected to water saturation evaluation, a plurality of reservoirs can be divided, the m and n values correspond to a plurality of m and n values, and the m and n are dynamic parameters in the whole research depth, so that the water saturation result of each reservoir is more accurate.
In order to better understand the effect of the invention, the method is applied to a compact sandstone logging interpretation method in a Tarim basin library vehicle area, the calculation method of the cementation index m and the saturation index n in the area is obtained by fitting the logging curve fractal dimension and the rock-electricity experimental parameters of 8 intervals, fig. 2 is an intersection graph of the correlation dimension and the cementation index in the embodiment, and fig. 3 is an intersection graph of the correlation dimension and the saturation index in the embodiment.
The linear relational expression of the bond index and the associated dimension and the linear relational expression of the saturation index and the associated dimension obtained by the intersection graph by adopting a linear fitting method are sequentially as follows: m-0.1413 Dm +1.9962 and n-0.1071 Dn + 2.3155.
And fitting the cementing index of the rock electric experiment in the region with loga to obtain: m is 1.8221-1.05 loga.
Taking a well in a certain basin in the western part of China as an example, the method is used for calculating the correlation dimension, establishing a cementing index and saturation index and correlation dimension fitting formula, and obtaining the cementing index and the saturation index in a layering way, which is shown in table 1. Substituting into the Archie's formula, the calculated saturation results are shown in FIG. 4. Testing oil in a layer section of 69660 m to 7000m, wherein the oil-water ratio is 82: and 18, testing gas to obtain a gas layer. The water saturation calculated by the fractal method is compared with the mercury intrusion saturation, the average error is 7.06 percent, and the method is correct; the relative error of the water saturation value calculated by using the parameters of the fixed values m, n and a is 25.33 percent, and the results of three saturation calculation methods are shown in a table 2. It can be seen that the water saturation calculated by the fractal dimension method has the highest accuracy.
TABLE 1
| Depth (m) | Layer thickness | Dn | Dm | m | n | a |
| 6960.5—6963.0 | 2.5 | 3 | 0.77 | 1.89 | 1.99 | 0.87 |
| 6963.0—6964.5 | 1.5 | 2.78 | 0.26 | 1.96 | 2.02 | 0.74 |
| 6966.0—6967.0 | 1 | 3.71 | 0.11 | 1.98 | 1.92 | 0.71 |
| 6967.5—6969.5 | 2 | 3.46 | 1.18 | 1.83 | 1.94 | 0.98 |
| 6969.5—6971.5 | 2 | 4.39 | 0.35 | 1.95 | 1.85 | 0.76 |
| 6973.0—6976.0 | 3 | 4.07 | 1.84 | 1.74 | 1.88 | 1.21 |
| 6977.0—6978.5 | 1.5 | 3.43 | 1.41 | 1.80 | 1.95 | 1.06 |
| 6980.5—6986.5 | 6 | 4.77 | 1.30 | 1.81 | 1.80 | 1.02 |
| 6986.5—6994.5 | 8 | 4.89 | 2.26 | 1.68 | 1.79 | 1.37 |
| 6994.5—7000.5 | 6 | 4.51 | 2.00 | 1.71 | 1.83 | 1.27 |
TABLE 2
| Depth/m | Mercury intrusion/% | Fractal method/% | Fixed parameter/%) |
| 6974.80 | 39.80 | 32.19 | 11.77 |
| 6975.27 | 27.53 | 25.42 | 7.54 |
| 6978.01 | 32.59 | 21.14 | 4.62 |
In summary, the method for measuring the water saturation of the tight sandstone reservoir according to the embodiment of the present invention respectively obtains the logging fractal dimension related to the cementation index and the logging fractal dimension related to the saturation index, respectively performs linear fitting to establish the relational expression between the cementation index and the saturation index and the fractal dimension through the m and n values obtained by logging the rock-electricity experiment of the reservoir corresponding to the well, obtains the cementation index and the saturation index of the interval through the known relational expression of linear fitting in the rock-electricity experiment in the well to be measured without the rock-electricity experiment, and finally calculates the water saturation of the interval through the Archie's formula and the parameters thereof. The overall process considers the variation of m and n values caused by the heterogeneity of the tight sandstone reservoir, a dynamic m and n value shape solving method is constructed, a fixed value is not adopted in the calculation of the water saturation, the calculation result is more accurate, the actual stratum condition is more met, and the method is more suitable for the measurement of the water saturation of the tight sandstone reservoir.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application to enable one skilled in the art to make and use various exemplary embodiments of the invention and various alternatives and modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims and their equivalents.
Claims (7)
1. A method for measuring the water saturation of a tight sandstone reservoir is characterized by comprising the following steps:
obtaining well logs of multiple categories of each reservoir through known rock-electricity experiments of cores of multiple reservoirs;
calculating the correlation dimension of the log of each category of each reservoir;
obtaining a first fractal dimension and a second fractal dimension of each reservoir according to the correlation dimension of the logging curve of each reservoir, wherein the first fractal dimension of each reservoir is related to the cementation index of the reservoir, and the second fractal dimension of each reservoir is related to the saturation index of the reservoir;
establishing a first linear relation between the first fractal dimension of each reservoir and the cementation index of the reservoir by adopting a linear fitting method, and establishing a second linear relation between the second fractal dimension of each reservoir and the saturation index of the reservoir;
establishing a linear relation between the cementation index of each reservoir and the loga according to the rock electricity experiments of the rock cores of the reservoirs, wherein a is a parameter in an Archie formula;
dividing a well to be tested into a plurality of reservoirs;
calculating the cementation index and the saturation index of each reservoir to be logged according to the first linear relational expression and the second linear relational expression; and
and calculating the water saturation of each reservoir to be logged based on the Archie's formula.
2. The method of measuring water saturation for tight sandstone reservoirs of claim 1, wherein the plurality of categories of well logs comprises: acoustic time difference log, compensated neutron log, compensated density log, and resistivity log.
3. The method of measuring water saturation for tight sandstone reservoirs of claim 2, wherein calculating the correlation dimension for the well log for each class of each reservoir comprises:
for a well log, first, time series X is used1,X2,...,XNGiven an initial value m of the embedding dimension0Reconstructing the phase space to obtain a new sequence { Yi }, wherein X1,X2,...,XNA spherical box with a radius r and taking Br (Xi) as a center as a point on the attractor in a phase space as a reference point Xi;
determining distances r for all point pairs in the new sequenceijAnd distances r of all point pairsijIs compared with r to determine rijA number of point pairs less than r;
calculating a correlation integral C (r), wherein the correlation integral C (r) is rijThe proportion of the point pairs smaller than r in all the point pairs;
obtaining the corresponding m by least square fitting0Estimated value of the correlation dimension d (m)0)；
Increase m0According to the above steps, re-calculating the correlation dimension estimate d (m)0) Up to the estimated value of the correlation dimension d (m)0) Is maintained within a preset range, and m is recorded0A final value of; and
according to said m0And (3) making an intersection graph of LnC (r) -Lnr, selecting a section with linearity larger than a certain value for linear fitting, and calculating a slope value of a fitting straight line, wherein the slope value is the correlation dimension of the logging curve.
4. The method of measuring water saturation for tight sandstone reservoirs of claim 3, wherein deriving the first fractal dimension and the second fractal dimension based on the correlation dimension of the log for each reservoir comprises:
determining the first fractal dimension D from a first patternmWherein the first formula is Dm＝[(Dcnl+Dden)+2*Dac]/4 wherein DcnlFor the correlation dimension, D, of the compensated neutron logdenFor the correlation dimension, D, of the compensated density logacThe correlation dimension of the acoustic moveout log is taken as the correlation dimension of the acoustic moveout log; and
if D ism≥DrtDetermining said second fractal dimension D according to a second equationnOtherwise, determining the second fractal dimension D according to a third equationnWherein the second formula is Dn＝DmThe third formula is Dn＝DrtWherein D isrtIs the correlation dimension of the resistivity log.
5. Such asThe method of measuring water saturation for tight sandstone reservoirs of claim 4, wherein the first linear relationship is m-km*Dm+bmWherein m represents the cementation index, kmAnd bmAre all fitting coefficients.
6. The method of measuring water saturation for tight sandstone reservoir of claim 5, wherein the second linear relationship is n-kn*Dn+bnWherein n represents the saturation index, knAnd bnAre all fitting coefficients.
7. The method of measuring water saturation for tight sandstone reservoir of claim 6, wherein the Archie's formula is
Wherein S iswFor water saturation, a and b are both lithology-related constants, RwIn order to be the formation water resistivity,
is porosity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010774361.7A CN111894567A (en) | 2020-08-04 | 2020-08-04 | Water saturation measuring method suitable for tight sandstone reservoir |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010774361.7A CN111894567A (en) | 2020-08-04 | 2020-08-04 | Water saturation measuring method suitable for tight sandstone reservoir |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111894567A true CN111894567A (en) | 2020-11-06 |
Family
ID=73245464
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010774361.7A Pending CN111894567A (en) | 2020-08-04 | 2020-08-04 | Water saturation measuring method suitable for tight sandstone reservoir |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111894567A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114037805A (en) * | 2021-10-26 | 2022-02-11 | 重庆科技学院 | Unconventional reservoir saturation model construction method |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB9924829D0 (en) * | 1998-11-10 | 1999-12-22 | Schlumberger Ltd | Method for interpreting carbonate reservoirs |
| CN105114064A (en) * | 2015-08-04 | 2015-12-02 | 中国石油天然气股份有限公司 | Method for determining saturation of compact sandstone reservoir |
| CN107918158A (en) * | 2016-10-11 | 2018-04-17 | 中国石油天然气股份有限公司 | The computational methods and device of a kind of litho-electric parameters |
| US20180246999A1 (en) * | 2015-11-18 | 2018-08-30 | Petrochina Company Limited | Stratum component optimization determination method and device |
| CN110146940A (en) * | 2019-04-04 | 2019-08-20 | 中国石油大学(华东) | A kind of gas reservoir irreducible water saturation, gas reservoir moveable water range determining method and device |
| CN110554441A (en) * | 2019-08-16 | 2019-12-10 | 中国石油天然气集团有限公司 | compact sandstone gas saturation calculation method based on calcareous content correction |
| CN110847901A (en) * | 2019-12-11 | 2020-02-28 | 成都理工大学 | Method for identifying fluid of underwater compact sandstone reservoir in variable-salinity stratum |
-
2020
- 2020-08-04 CN CN202010774361.7A patent/CN111894567A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB9924829D0 (en) * | 1998-11-10 | 1999-12-22 | Schlumberger Ltd | Method for interpreting carbonate reservoirs |
| CN105114064A (en) * | 2015-08-04 | 2015-12-02 | 中国石油天然气股份有限公司 | Method for determining saturation of compact sandstone reservoir |
| US20180246999A1 (en) * | 2015-11-18 | 2018-08-30 | Petrochina Company Limited | Stratum component optimization determination method and device |
| CN107918158A (en) * | 2016-10-11 | 2018-04-17 | 中国石油天然气股份有限公司 | The computational methods and device of a kind of litho-electric parameters |
| CN110146940A (en) * | 2019-04-04 | 2019-08-20 | 中国石油大学(华东) | A kind of gas reservoir irreducible water saturation, gas reservoir moveable water range determining method and device |
| CN110554441A (en) * | 2019-08-16 | 2019-12-10 | 中国石油天然气集团有限公司 | compact sandstone gas saturation calculation method based on calcareous content correction |
| CN110847901A (en) * | 2019-12-11 | 2020-02-28 | 成都理工大学 | Method for identifying fluid of underwater compact sandstone reservoir in variable-salinity stratum |
Non-Patent Citations (8)
| Title |
|---|
| LING PENG: ""Estimating irreducible water saturation and permeability of sandstones from nuclear magnetic resonance measurements by fractal analysis"", 《MARINE AND PETROLEUM GEOLOGY》 * |
| XIAOJUN CHEN: ""An improved model for permeability estimation in low permeable porous media based on fractal geometry and modified Hagen-Poiseuille flow"", 《FUEL》 * |
| ZE BAI，MAOJIN TAN: ""Analysis of low-resistivity oil pay and fluid typing method of Chang 81 Member, Yanchang Formation in Huanxian area, Ordos Basin, China"", 《JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING》 * |
| 伍泽云，等: ""低孔低渗储层中确定Archie参数m与a的改进方法"", 《石油天然气学报》 * |
| 吴怀宇: "《时间序列分析与综合》", 31 December 2004 * |
| 姜虹: ""普光地区碳酸盐岩储层测井评价方法"", 《中国优秀硕士学位论文全文数据库 (基础科学辑)》 * |
| 王天波，等: ""用分形理论确定m、n值的方法及其应用"", 《测井技术》 * |
| 高红贤，等: ""YB气田大安寨段储层参数计算方法"", 《断块油气成》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114037805A (en) * | 2021-10-26 | 2022-02-11 | 重庆科技学院 | Unconventional reservoir saturation model construction method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109753755B (en) | Method for determining water saturation of reservoir | |
| CN112698399B (en) | Method and system for quantitatively predicting efficient reservoir based on vibration measurement linkage constraint of conglomerate well | |
| CN106897531B (en) | Quantitative evaluation method for permeability of low-permeability limestone reservoir | |
| CN112796738A (en) | Stratum permeability calculation method combining array acoustic logging and conventional logging | |
| CN111008482B (en) | Metamorphic rock reservoir water saturation calculation method and device | |
| CN111894567A (en) | Water saturation measuring method suitable for tight sandstone reservoir | |
| CN109667576B (en) | High-salinity-formation-factor low-resistance oil layer logging identification method | |
| CN109901238B (en) | High-stress formation resistivity correction method based on stress difference resistivity experiment | |
| CN110344822B (en) | Determination method of water saturation of calcareous compact reservoir | |
| CN112115592A (en) | Large-inclination/horizontal well resistivity correction method based on rock physics experiment | |
| CN106593423A (en) | Method and device for identifying oil reservoir fluid types | |
| CN107762490A (en) | A kind of horizontal well is based on dual laterolog true resistivity inversion method | |
| CN114185108B (en) | Crack porosity determination method, storage medium, and computer device | |
| CN112419493B (en) | Shale reservoir three-dimensional attribute model building method and device | |
| CN112147697B (en) | Method and device for calculating tight reservoir fracture porosity by utilizing double lateral curves | |
| CN109994161B (en) | Method for calculating organic carbon content of stratum by combining trend baseline method with dynamic linkage method | |
| CN114542055A (en) | Method and device for focusing and processing array induction logging data of inclined well or inclined stratum | |
| CN114109349B (en) | Method for determining porosity index/saturation index of tight sandstone reservoir | |
| CN107818185B (en) | Method for acquiring tight sandstone formation factor | |
| CN112711076B (en) | Method and apparatus for extracting depth of penetration of mud into formation in petroleum drilling | |
| CN108875109B (en) | Method and system for predicting abnormal formation pressure | |
| CN114046145B (en) | Reservoir fluid identification and saturation determination method and device | |
| CN113971351B (en) | Method and device for determining porosity of crack | |
| CN116025333A (en) | Method and system for inverting salt-bearing reservoir saturation based on corrected resistivity | |
| CN111984903B (en) | Calculation characterization method and system for TOC (total organic carbon) and oil saturation of shale reservoir |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20201106 |
|
| RJ01 | Rejection of invention patent application after publication |