CN107065033A - A kind of recognition methods of tight sandstone reservoir microcrack development and device - Google Patents
A kind of recognition methods of tight sandstone reservoir microcrack development and device Download PDFInfo
- Publication number
- CN107065033A CN107065033A CN201710421072.7A CN201710421072A CN107065033A CN 107065033 A CN107065033 A CN 107065033A CN 201710421072 A CN201710421072 A CN 201710421072A CN 107065033 A CN107065033 A CN 107065033A
- Authority
- CN
- China
- Prior art keywords
- logarithm
- saturation degree
- scatter diagram
- data point
- microcrack
- 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.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V9/00—Prospecting or detecting by methods not provided for in groups G01V1/00 - G01V8/00
Abstract
The invention provides a kind of recognition methods of tight sandstone reservoir microcrack development and device.The recognition methods includes：Obtain rock sample in purpose stratum and enter mercury saturation degree under different capillary pressures；Calculate respectively the capillary pressure logarithm and it is described enter mercury saturation degree logarithm；According to the logarithm of the capillary pressure and it is described enter mercury saturation degree logarithm build scatter diagram；Linear fit is carried out to the target data point in the scatter diagram, to obtain target fitting a straight line；According to the slope of the target fitting a straight line, whether identification purpose stratum microcrack develops.The technical scheme that the present invention is provided is simple and convenient, and carry out quantitative judge whether can be developed to microcrack.
Description
Technical field
The present invention relates to a kind of recognition methods of tight sandstone reservoir microcrack development and device, belong to geoanalytical techniques
Field.
Background technology
How the study hotspot that quantitative assessment is always this area is carried out to tight sand microcrack, this is to follow-up reservoir
Explore and develop and be most important.
By taking Ordos Basin in Palaeozoic as an example, it has abundant natural gas resource.Third time resource assessment result table
Bright, there are 1.5 trillion side's natural gas resources the basin south Paleozoic group, and exploration prospect is very huge.Gansu Province Dong Youqu Wei Yu E Erduo
This basin west and south, across Qingyang, the city of Pingliang two, area is about 5 × 104km2, the 25% of basin our department area is accounted for, is long celebrating stone
The main battlefield of exploration activity exploitation.Because Gansu Province east area construction is complicated, undesirable, the current brill of early stage natural gas exploration achievement
Visit result show this area's gassiness series of strata it is relatively single, effective gas-bearing sandstone thinner thickness and be distributed it is unstable, for meet exploration
Work, is badly in need of a kind of method for being capable of quantitative assessment tight sand microcrack of research.
Mainly have following several currently used for the method for evaluating microcrack：
1) crack is recognized using imaging logging：Mainly fine and close natural gas reservoirs are known using FMI imaging logging techniques
Other and evaluation, but this method is limited due to resolution ratio etc., and conclusion can only be provided from macroscopic perspective, it is impossible to effectively identification and evaluation
The crack developed in tight sandstone reservoir.For example, using the micro- resistance imager (FMI) of full hole of Schlumberger to E Er
When Long1Jing, the Long2Jing and celebrating 3 wells of spy on many 1 section of this basin mountains are studied, it is found that it intuitively can only add to the crack of macroscopic view
To recognize, and it is difficult to effectively recognize microcrack (micron to the other crack of grade).
2) crack is recognized using ESEM：It is main to utilize rock pore of the instruments such as SEM, FIB-SEM to micro-nano-scale
Gap is characterized, and this method is primarily present following drawback：1. laboratory apparatus cost is high, and requires high to the making of sample, from
And it is also of a relatively high to result in experimental expenses；2. due to the sample size very little of ESEM, although the dissection to partial structurtes
More fine, particularly morphology is rested in the range of nanoscale, but the technology describes aspect, quantitative assessment hole knot more
Structure it is limited in one's ability；3. the primary identification with secondary fracture is also had some limitations, especially because sample very little,
Influence of some induced fractures produced during sample preparation to result is very big.
3) reservoir is evaluated using high-pressure mercury experiment：Conventional high-pressure mercury experiment can only obtain it is a series of on
Duty pressure (MPa), pore throat half in the parameter of pore throat character, such as replacement pressure (MPa), maximum pore throat radius (μm), saturation degree
Footpath intermediate value (μm), pore throat radius average value (μm), uniformity coefficient, lithology factor, maximum mercury saturation degree (%), efficiency of mercury withdrawal
(%), structural coefficient, feature structure coefficient, skewness (are also known as flexure, kurtosis, coefficient of variation etc..But, these parameters can not
Information on Reservoir Fracture is directly provided.
Therefore it provides a kind of recognition methods of tight sandstone reservoir microcrack development, whether microcrack can be developed into
Row quantitative judge turns into this area technical problem urgently to be resolved hurrily.
The content of the invention
In order to solve the above technical problems, it is an object of the invention to provide a kind of identification side of tight sand microcrack development
Method and device.Whether the technical scheme that the present invention is provided fast and effeciently the microcrack of tight sandstone reservoir can develop and known
Not, and quantitative data is provided.
To reach above-mentioned purpose, the invention provides a kind of recognition methods of tight sand microcrack development, this method bag
Include：
Obtain rock sample in purpose stratum and enter mercury saturation degree under different capillary pressures；
Calculate respectively the capillary pressure logarithm and it is described enter mercury saturation degree logarithm；
Logarithm based on the capillary pressure and it is described enter mercury saturation degree logarithm build scatter diagram；
Linear fit is carried out to the target data point in the scatter diagram, to obtain target fitting a straight line；
According to the slope of the target fitting a straight line, whether identification purpose stratum microcrack develops.
In the technical scheme that provides of the present invention, calculate respectively the capillary pressure logarithm and it is described enter mercury saturation degree
Logarithm when, the functional form of logarithm can include Log, Ln, Log2Or Log10, not limited to this.
In the above-mentioned methods, it is preferable that according to the logarithm of the capillary pressure and it is described enter mercury saturation degree logarithm structure
Building scatter diagram includes：Using the logarithm of the capillary pressure as abscissa, using it is described enter mercury saturation degree logarithm as ordinate, structure
Build scatter diagram.
In the above-mentioned methods, it is preferable that this method also includes：Distribution to data point in the scatter diagram is analyzed,
To obtain the regularity of distribution of data point in the scatter diagram；Wherein, the regularity of distribution of data point is as follows in the scatter diagram：It is described
The distribution of data point is in the trend of one section or more than two sections different straight lines in scatter diagram；When the trend in more than two sections different straight lines
When, the slope of every section of straight line is differed.
In the above-mentioned methods, it is preferable that the number of targets strong point is chosen by following operation：To in the scatter diagram
Data point is grouped, and the data point in same section of trends of straight line distribution is divided into one group；On the basis of the origin of coordinates, from draw
That group data point near the origin of coordinates is chosen as number of targets strong point in the group divided.When being grouped to data point,
It is possible that situations below：20 data points are for example sequentially distributed on scatter diagram, the distribution of preceding 6 points (first group) is
Substantially in the higher straight line of a slope, the distribution trend of rear 13 points (second group) is then substantially shallower in another slope
Straight line, wherein, the 7th point is similar is in the crossed position, and being divided into first group can form straight together with preceding 6 points
Line, and straight line can also be formed together with rear 13 points by being divided into second group.In this case can so it carry out：1. first
7th point is divided into after first group, linear fit is carried out to two groups of data respectively, two fitting a straight lines is obtained and is designated as L1 respectively
(first group of data) and L2 (second group of data)；2. and then the 7th data point is divided into second group, similarly respectively to two groups
Data carry out linear fit, obtain L1 ' (first group of data) and L2 ' (second group of data)；3. it is last by the L1 1. obtained and L2
Linear fit precision be compared respectively with the L1 ' and the precision of L2 ' linear fits that 2. obtain, choose higher that of precision
The situation of kind is grouped；In a practical situation, when there is above-mentioned situation, the 7th point is assigned to first group or second group to final
Recognition result influence it is little, can almost ignore.
In the above-mentioned methods, it is preferable that according to the slope of the target fitting a straight line, purpose stratum microcrack is recognized
Whether development includes：
During slope≤1, the microcrack agensis of purpose stratum is determined；
Slope>When 1, the microcrack development of purpose stratum is determined.
In the technical scheme that the present invention is provided, " microcrack " is mainly one kind that fracture is carried out according to width
Classification, it is primarily referred to as the crack of micron level.
In the technical scheme that provides of the present invention, " the high-pressure mercury experiment " be also referred to as " constant pressure pressure mercury is tested " or
" conventional pressure mercury experiment ", it is to determine one of main method of rock capillary pressure curve, can by high-pressure mercury experiment
To obtain the relation curve of mercury pressure and mercury saturation degree, also referred to as capillary pressure curve or intrusive mercury curve.The intrusive mercury curve
Including entering mercury section and mercury ejection section, enter mercury section reflection is that into during mercury, pressure is gradually increasing, and mercury saturation degree is continuously increased；And
Mercury ejection section reflection be mercury ejection during, pressure is gradually reduced, and mercury is gradually withdrawn from rock core, and mercury saturation degree is constantly reduced.
In the technical scheme that the present invention is provided, described " entering mercury saturation degree under different capillary pressures " can also be referred to as " different
The mercury saturation degree entered under mercury pressure ", what is mainly reflected is：Enter the mercury stage, the mercury saturation degree under different capillary pressures is described
" entering mercury saturation degree under different capillary pressures " enters mercury segment data for intrusive mercury curve.
In pressure mercury experiment, with the continuous increase for entering mercury pressure, mercury constantly enters in less and less hole, due to
Mercury is non-wetted phase relative to rock, and contact angle is more constant, according to Washburn (1921) equation, and a certain moment enters
Mercury pressure (capillary pressure) value is corresponding with the aperture at the moment, therefore capillary pressure curve can provide corresponding hole chi
Degree and distributed intelligence.
The technical scheme that the present invention is provided has carried out deep exploratory development to whether tight sand microcrack develops, mainly
Research idea is as described below：
1) note mercury is carried out to rock sample under the conditions of different capillary pressures by high-pressure mercury experiment, to obtain different capillarys
Pipe pressure condition it is corresponding enter mercury saturation data；Then creatively capillary pressure curve is mutually tied with fractals principle
Close, based on capillary (cylinder) form, the Primary Construction functional relation entered between mercury saturation degree and capillary pressure
Formula：SHg=aPc(D-2), in formula, SHg is that, into mercury saturation degree, Pc is capillary pressure, and D is point shape of hole, and a is coefficient；
2) both sides of above-mentioned functional relation are taken the logarithm, obtain Log (SHg)=(D-2) × Log (aPc)=(D-2) ×
Log(aPc)+(D-2)×Log(a)；It can thus be seen that above-mentioned functional relation, both sides can obtain one closely after taking the logarithm
As straight line, the slope K of the straight line is D-2, i.e. D=K+2；
3) fractals principle is combined, the number range for determining point shape of hole is：2<D<3, obtain 0<K<1；Wherein, D
Value shows that the distribution of pore throat is more homogeneous, reservoir properties are better closer to 2；
4) determine on the basis of the origin of coordinates, during the slope K of first paragraph point shape≤1, microcrack agensis；First paragraph point shape
Slope K 1>When 1, microcrack development.
In the above-mentioned methods, it is preferable that before high-pressure mercury experiment is carried out, this method is also wrapped to tight sandstone reservoir
The step of rock sample is pre-processed.For example contain oil gas in rock sample, then soxhlet type should be used to carry out oil suction to sample, then dried
Do to constant weight, pretreatment can reduce or eliminate the interference of foreign matter, the different capillary pressures for obtaining high-pressure mercury experiment
Under power to enter mercury saturation data more accurate.
In the above-mentioned methods, it is preferable that high-pressure mercury experiment is carried out to the rock sample of tight sandstone reservoir, to obtain fine and close sand
Enter mercury saturation degree of the rock sample of rock reservoir under different capillary pressures includes：Different capillary pressures are set gradually from small to large
Power, and under different capillary pressures to rock sample carry out high-pressure mercury experiment, with obtain different capillary pressures it is corresponding enter mercury
Saturation degree.In actual mechanical process, whole experimentation is carried out automatically in high-pressure mercury instrument, the setting of pressure
Have a both of which, one kind is continuous supercharging, one kind be noncontinuity, staged supercharging (step-length of supercharging can be set, and
Stayed for some time at each pressure value so that mercury can be well into all holes under the pressure), provided in the present invention
In technical scheme, from noncontinuity, staged boost mode, the mercury saturation degree that difference is entered under mercury pressure, the mercury can be obtained
Saturation degree is into mercury saturation degree.
In the above-mentioned methods, it is preferable that calculate respectively the capillary pressure logarithm and it is described enter mercury saturation degree pair
Number includes：To it is described enter mercury saturation degree be corrected, to enter mercury saturation degree after being corrected；The capillary pressure is calculated respectively
The logarithm for entering mercury saturation degree after the logarithm of power, and the correction.When doing high-pressure mercury experiment, initial enters the mercury stage
In, the increase for entering mercury quantity is due to false intrusive body caused by laminating of the non-wetted phase mercury in the hole recess of rock sample rough surface
Product, with the gradually increase of pressure, hole is recessed to be taken by mercury, and now mercury does not actually enter pore throat system also, and pressure does not have yet
Replacement pressure is reached, if this portion cavity volume is accumulated to the entering in mercury quantity of total pore throat system, can be caused into entering mercury saturation degree
Numerical value is (this phenomenon is referred to as " hemp skin effect ") bigger than normal, is corrected and can eliminate that " hemp skin is imitated to entering mercury saturation data
Should ".
In a detailed embodiment, this method includes：
Rock sample in purpose stratum in acquisition tight sandstone reservoir；
Obtain rock sample in purpose stratum and enter mercury saturation degree under different capillary pressures；
Calculate respectively the capillary pressure logarithm and it is described enter mercury saturation degree logarithm；
Using the logarithm of the capillary pressure as abscissa, using it is described enter mercury saturation degree logarithm as ordinate, build dissipate
Point diagram；
Distribution to data point in the scatter diagram is analyzed, and is advised with the distribution for obtaining data point in the scatter diagram
Rule；Wherein, the regularity of distribution of data point is as follows in the scatter diagram：The distribution of data point is in one section or two sections in the scatter diagram
The trend of above difference straight line；When the trend in more than two sections different straight lines, the slope of every section of straight line is differed；
According to the regularity of distribution of data point in the scatter diagram, data point therein is grouped, will be straight in same section
The data point of line trend distribution is divided into one group；On the basis of the origin of coordinates, chosen from the group of division near the origin of coordinates
That group data point be used as number of targets strong point；
Linear fit is carried out to the target data point in scatter diagram, to obtain target fitting a straight line；
According to the slope of the target fitting a straight line, whether identification purpose stratum microcrack develops：
During slope≤1, the microcrack agensis of purpose stratum is determined；
Slope>When 1, the microcrack development of purpose stratum is determined.
The present invention still further provides a kind of identifying device of tight sand microcrack development, and the device includes：
Acquiring unit, mercury saturation degree is entered for obtaining rock sample in purpose stratum under different capillary pressures；
Computing unit, for calculate respectively the capillary pressure logarithm and it is described enter mercury saturation degree logarithm；
Construction unit, for the logarithm according to the capillary pressure and it is described enter mercury saturation degree logarithm build scatterplot
Figure；
Fitting unit is straight to obtain target fitting for carrying out linear fit to the target data point in the scatter diagram
Line；
Recognition unit, for the slope according to the target fitting a straight line, whether identification purpose stratum microcrack is sent out
Educate.
In said apparatus, it is preferred that the device also includes high-pressure mercury instrument, for carrying out high-pressure mercury to the rock sample
Experiment.The highest experimental pressure of conventional high-pressure mercury instrument is up to 60000psi (about 414MPa) at present, with experimental pressure
Scope is big, the characteristics of speed of experiment is fast.
In said apparatus, it is preferred that the construction unit is used for using the logarithm of the capillary pressure as abscissa, with
It is described enter mercury saturation degree logarithm be ordinate, build scatter diagram.
In said apparatus, it is preferred that the device also includes analytic unit, for being clicked through to the data in the scatter diagram
Row analysis, to obtain the regularity of distribution of data point in the scatter diagram；Wherein, the regularity of distribution of data point is such as in the scatter diagram
Under：
The distribution of data point in the scatter diagram is in the trend of one section or more than two sections different straight lines；When in more than two sections
During the trend of different straight lines, the slope of every section of straight line is differed.
In said apparatus, it is preferred that the device also includes choosing unit, for choosing target data according to following operation
Point：
According to the regularity of distribution of data point in the scatter diagram, data point therein is grouped, will be straight in same section
The data point of line trend distribution is divided into one group；On the basis of the origin of coordinates, chosen from the group of division near the origin of coordinates
That group data point be used as number of targets strong point.
In said apparatus, it is preferred that the recognition unit is used for the slope according to the target fitting a straight line, institute is recognized
State whether purpose stratum microcrack develops：
During slope≤1, the microcrack agensis of purpose stratum is determined；
Slope>When 1, the microcrack development of purpose stratum is determined.
In said apparatus, it is preferred that the computing unit also includes：
Correct subelement, for it is described enter mercury saturation degree be corrected, to enter mercury saturation degree after being corrected；
Computation subunit, the logarithm for calculating the capillary pressure respectively, and enter mercury saturation after the correction
The logarithm of degree.
Beneficial effects of the present invention：
1) technical scheme that the present invention is provided is simple and convenient, without the equipment that Electronic Speculum etc. is high, without complicated system
Sample process；
2) the characteristics of tight sandstone reservoir has low porosity and low permeability, its porosity is typically smaller than 10%, and permeability is typically smaller than
1mD, existing technological means is difficult effectively to recognize the microcrack wherein developed, and the technical scheme that the present invention is provided is by entering mercury
Whether saturation degree and capillary pressure can develop carry out quantitative judge to microcrack, and effectively overcoming existing means can not be to causing
Whether the microcrack in close sandstone reservoir, which develops, is identified, even if although the electron microscopy such as SEM, FIB-SEM can carry out it is micro-
Metrical scale, nanoscale are portrayed, but can only rest on topography aspect, it is impossible to carry out the shortcoming of quantitative judge；
3) technical scheme that the present invention is provided creatively is grouped to the data point in scatter diagram, will be straight in same section
The data point of line trend distribution is divided into one group；On the basis of the origin of coordinates, chosen from the group of division near the origin of coordinates
That group data point carry out linear fit as number of targets strong point, and to target data point to obtain target fitting a straight line, will
The direct quantitative criterion of identification that the slope of the target fitting a straight line of acquisition exists as microcrack, recognition result is accurately and reliably.
Brief description of the drawings
Fig. 1 is the flow chart of recognition methods provided in an embodiment of the present invention；
Fig. 2 is the scatter diagram of rock sample at the well 4111.84m of Gansu Province 13；
Fig. 3 is the scatter diagram of rock sample at the well 4700.98m of Gansu Province 6；
Fig. 4 is microscope figure below of rock core casting body flake at the well 4698.7m of Gansu Province 6；
Fig. 5 is microscope figure below that rock core casting body flake at 2 well 3797.3m is visited in city；
Fig. 6 is microscope figure below that rock sample inclusion enclave at 2 well 3809.73m is visited in city；
Fig. 7 is microscope figure below that rock sample inclusion enclave at 2 well 3797.3m is visited in city；
Fig. 8 is the structured flowchart of identifying device provided in an embodiment of the present invention.
Embodiment
In order to which technical characteristic, purpose and beneficial effect to the present invention are more clearly understood from, now to the skill of the present invention
Art scheme carry out it is described further below, but it is not intended that to the present invention can practical range restriction.
The embodiment of the present invention is using the southwestern Ordos Basin Gansu Province fine and close natural gas reservoirs of eastern Upper Paleozoic as research
Object is there is provided the recognition methods that a kind of tight sandstone reservoir microcrack is developed, as shown in figure 1, may comprise steps of：
Step S101：Obtain rock sample in purpose stratum and enter mercury saturation degree under different capillary pressures；
Obtain rock sample respectively out of different wells, as shown in table 1, can be to rock in order to ensure the accuracy of experimental data below
Sample is pre-processed, if containing oil gas in such as rock sample, can use soxhlet type to sample carry out oil suction, then dry to
Constant weight, pretreatment can eliminate disturbing factor, make experimental data below more accurate；
Carry out high-pressure mercury experiment (also referred to as constant pressure pressure mercury or conventional pressure mercury) respectively to above-mentioned rock sample：From small to large according to
It is secondary that different capillary pressures (being also referred to as into mercury pressure) are set, note mercury is carried out to rock sample under different capillary pressures, with
Obtain and enter mercury saturation degree SHg under different capillary pressure Pc.
Table 1
Note：Gas-bearing formation, poor gas-bearing formation develop microcrack, dried layer then microcrack agensis.
In the present embodiment, this area conventional meanses can be used by entering mercury saturation degree SHg metering, can in advance be located in rock sample
It is by Gas Industry standard (SY/T) 5346- according to the People's Republic of China (PRC) before high-pressure mercury experiment starts after reason terminates
2005 (Rock Capillary Pressure measurement), measure the gentle survey of perm-plug method of above-mentioned rock sample respectively
Porosity, can be determined into mercury saturation degree by means of the two parameters.
By taking rock sample at the well 4111.84m of Gansu Province 13 as an example, the rock sample is carried out after high-pressure mercury experiment, can obtain different capillarys
Enter mercury saturation degree SHg under pipe pressure Pc, the mercury saturation data that enters of acquisition can be corrected, as shown in table 2, in table 2
Enter mercury saturation data be it is corrected after data.
Step S102：Calculate respectively the capillary pressure logarithm and it is described enter mercury saturation degree logarithm；
In the present embodiment, the mercury saturation data that enters of acquisition can be corrected, bearing calibration is referred to (SY/
T) the record in 5346-2005 (Rock Capillary Pressure measurement), to eliminate the dry of " hemp skin effect "
Disturb, make the data of acquisition more accurate.
Calculate respectively capillary pressure Pc logarithm and correction after the logarithm for entering mercury saturation degree SHg；When calculating logarithm,
The functional form of logarithm can also be Ln, Log in addition to Log2、Log10Deng.
Step S103：According to the logarithm of the capillary pressure and it is described enter mercury saturation degree logarithm build scatter diagram；
With Log (SHg) be ordinate, Log (Pc) for abscissa, build scatter diagram.
By taking the scatter diagram of rock sample at the well 4111.84m of Gansu Province 13 as an example, the scatter diagram from Fig. 2 as shown in Fig. 2 can be found that
The distribution of data point is very regular, it can be seen that trend in alignment between preceding 6 data points, and remaining data point
Then into the trend of another straight line, also, the slope significant difference of this two straight lines is very big.
In addition, again by taking the scatter diagram of rock sample at the well 4700.98m of Gansu Province 6 as an example, the scatter diagram is as shown in figure 3, can from Fig. 3
To find the regularity of distribution in three-stage straight line of data point.
Step S104：Target data point in the scatter diagram is carried out linear fit to obtain target fitting a straight line；
According to the regularity of distribution of data point in scatter diagram, data point therein is grouped, will be become in same section of straight line
The data point of gesture distribution is divided into one group；On the basis of the origin of coordinates, chosen from the group of division near the origin of coordinates that
One group of data point is used as number of targets strong point.The regularity of distribution of data point is in scatter diagram：The distribution of data point is usual in scatter diagram
In the trend of one section or more than two sections different straight lines；When the trend in more than two sections different straight lines, the slope of every section of straight line is
Differ.
Linear fit is carried out to target data point, to obtain target fitting a straight line.
By taking the scatter diagram of rock sample at the well 4111.84m of Gansu Province 13 as an example (as shown in Figure 2), above 6 data points are in substantially in figure
The distribution trend of straight line, and remaining data point is in then the distribution trend of another straight line, and above 6 data points are carried out
Unitary once linear is fitted, and obtains target fitting a straight line, the target fitting a straight line can be designated as first paragraph straight line (L1), first paragraph
The slope K 1=2.629 of straight line, intercept a1=1.641；Remainder strong point can also carry out linear fit, obtained fitting a straight line
It can be designated as second segment straight line (L2), the slope K 2=0.129 of second segment straight line, intercept is a1=1.746.
Step S105：According to the slope of the target fitting a straight line, whether identifying purpose stratum microcrack develops；
During slope≤1, the microcrack agensis of purpose stratum is determined；
Slope>When 1, the microcrack development of purpose stratum is determined.
By taking the Jing4111.84mChu of Gansu Province 13 rock sample as an example, the slope K 1=2.629 of obtained first paragraph straight line (L1) is fitted,
Due to K1>1, determine that microcrack is developed at the well 4111.84m of Gansu Province 13.The recognition result of other wells is as shown in table 1.
Table 2
As can be seen from Table 1：1) the data point aggregate performance of dried layer is the regularity of distribution of two-part straight line, and gas-bearing formation,
The data of poor gas-bearing formation may then show the regularity of distribution of three-stage straight line.2) slope K 1 of gas-bearing formation and poor gas-bearing formation first paragraph straight line
The significantly greater than slope K 1 of dried layer first paragraph straight line, and find that the slope K 1 of gas-bearing formation and poor gas-bearing formation first paragraph straight line is not almost small
In 1 situation；Wherein, the average value of the slope K 1 of gas-bearing formation first paragraph straight line is 2.45, the slope K 1 of poor gas-bearing formation first paragraph straight line
Average value be 4.5, and the slope K 1 of dry gas layer first paragraph straight line is most of is less than 1, and another part is located between 1-2.With
Dry gas layer is compared, and the reason for causing the slope K 1 of gas-bearing formation and poor gas-bearing formation to deviate considerably from 1 is as follows：According to fractal principle, in nature
The material characteristic that has " self similarity " be referred to as a point shape, when " self similarity " property is higher, then fractal dimension is worth within the specific limits
Lower, therefore, the K1 in gas-bearing formation and poor gas-bearing formation deviates considerably from 1, illustrates that its " self similarity " property is very low, due to be using capillary as
Basic form carries out the derivation of equation, then by this model heap to fractal theory out, the basis of its " self similarity " should be
Capillary, if K1>1 (i.e. D>3), then illustrate that it deviate from this model, can speculate gas-bearing formation with the K1 values in poor gas-bearing formation significantly
It is due to that other " space types " occupy leading in interstitial space, and this " space type " should be crack more than 1.3)
Gas-bearing formation, poor gas-bearing formation develop microcrack, dried layer then microcrack agensis.
In addition, the corresponding pore diameter range of six points on first paragraph straight line L1 is can be seen that with Fig. 2 with reference to table 2 at 1-4 μm
Between change, therefore, the microcrack that can be characterized here is micro-meter scale.
For the reliability of recognition result in proof list 1, comprehensive casting body flake and fluid inclusion commonly used in the art
Research method is visited 2 wells to above-mentioned Long6Jing and city and studied.
By the gas well gas of Gansu Province 6 layer (4698.7m) rock core be made casting body flake observed under the microscope (as shown in figure 4, from
Arrow head part in figure is, it is apparent that mineral grain develops target on obviously microcrack, its corresponding scatter diagram
1) slope of fitting a straight line is significantly greater than, it is obvious that developing many microcracks in mineral grain；Likewise, city is visited into 2
The rock core of well dried layer (3797.3m) is made casting body flake and is observed (bright in Fig. 5 particle as shown in figure 5, compared with Fig. 4
The slope of target fitting a straight line is less than 1), it can clearly be seen that mineral grain on microfissue agensis, its corresponding scatter diagram
In microcrack and agensis, it is but cementing in the later stage even if there is part microcrack.As can be seen here, the method that the present invention is provided is obtained
To recognition result be reliable.
The sample that city is visited into the poor gas-bearing formation (3809.73m) of 2 wells is made inclusion enclave and observed under the microscope (such as Fig. 6 institutes
Show), it is obvious that microcrack is developed, the fracture phenomena of mineral grain is apparent from, along some microcracks, finds gassiness
Inclusion enclave is distributed along microcrack, and this controls natural gas accumulation to microcrack there is provided strong evidence from into Tibetan angle；
Likewise, the sample that city is visited into 2 well dried layer (3797.3m) is made inclusion enclave and is observed (as shown in Figure 7), it can clearly be seen that
Mineral grain is more complete, and microcrack is less developed, and healing microcrack is only observed in the figure 7.As can be seen here, the present invention is carried
The recognition result that the technical scheme of confession is obtained is reliable.
Based on same inventive concept, a kind of knowledge of tight sandstone reservoir microcrack development is additionally provided in the embodiment of the present invention
Other device, as described in the following examples.Because the identifying device that tight sandstone reservoir microcrack is developed solves the principle of problem
It is similar to the recognition methods that tight sandstone reservoir microcrack is developed, therefore the identifying device of tight sandstone reservoir microcrack development
Implementation may refer to the implementation of the recognition methods of tight sandstone reservoir microcrack development, repeats part and repeats no more.It is following to be made
, term " unit " or " module " can realize the combination of the software and/or hardware of predetermined function.Although following examples
Described device is preferably realized with software, but hardware, or the combination of software and hardware realization be also may be simultaneously
It is contemplated.
Fig. 8 is a kind of structured flowchart of the identifying device of the tight sandstone reservoir microcrack development of the embodiment of the present invention, should
Device includes：Acquiring unit 801, computing unit 802, construction unit 803, fitting unit 804, recognition unit 805 are below to this
Structure is illustrated.
Acquiring unit 801, mercury saturation degree is entered for obtaining rock sample in purpose stratum under different capillary pressures；
Computing unit 802, for calculate respectively the capillary pressure logarithm and it is described enter mercury saturation degree logarithm；
Construction unit 803, for the logarithm according to the capillary pressure and it is described enter mercury saturation degree logarithm build dissipate
Point diagram；
Fitting unit 804, is fitted for carrying out linear fit to the target data point in the scatter diagram with obtaining target
Straight line；
Recognition unit 805, for the slope according to the target fitting a straight line, whether identification purpose stratum microcrack
Development.
In one embodiment, the construction unit 803 is specific can be used for using the logarithm of the capillary pressure as horizontal stroke
Coordinate, using it is described enter mercury saturation degree logarithm as ordinate, build scatter diagram.
In one embodiment, the specific slope that can be used for according to the target fitting a straight line of the recognition unit 805,
Recognize whether purpose stratum microcrack develops：
During slope≤1, the microcrack agensis of purpose stratum is determined；
Slope>When 1, the microcrack development of purpose stratum is determined.
In one embodiment, the computing unit 802 can also include：
Correct subelement, for it is described enter mercury saturation degree be corrected, to enter mercury saturation degree after being corrected；
Computation subunit, the logarithm for calculating the capillary pressure respectively, and enter mercury saturation after the correction
The logarithm of degree.
In one embodiment, the device can also include analytic unit, for being clicked through to the data in the scatter diagram
Row analysis, to obtain the regularity of distribution of data point in the scatter diagram；Wherein, the regularity of distribution of data point is such as in the scatter diagram
It is lower described：
The distribution of data point is in the trend of one section or more than two sections different straight lines in the scatter diagram；
When the trend in more than two sections different straight lines, the slope of every section of straight line is differed.
In one embodiment, the device can also include choosing unit, for choosing target data according to following operation
Point：
Data point in the scatter diagram is grouped, the data point in same section of trends of straight line distribution is divided into one
Group；On the basis of the origin of coordinates, that group data point near the origin of coordinates is chosen from the group of division as target data
Point.
As can be seen from the above description, the embodiment of the present invention realizes following technique effect：Obtain in purpose stratum
Rock sample enters mercury saturation degree under different capillary pressures；Calculate respectively the capillary pressure logarithm and it is described enter mercury saturation
The logarithm of degree；According to the logarithm of the capillary pressure and it is described enter mercury saturation degree logarithm build scatter diagram；To the scatterplot
Target data point in figure carries out linear fit, to obtain target fitting a straight line；According to the slope of the target fitting a straight line, know
Whether not described purpose stratum microcrack develops, and solves conventional technical means is difficult to whether develop tight sandstone reservoir crack
The problem of effectively being recognized, is whether tight sandstone reservoir crack develops method there is provided quantitative judge, be oil-gas reservoir into
Because the research of Dominated Factors provides strong basis.
Obviously, those skilled in the art should be understood that each module or each step of the above-mentioned embodiment of the present invention can be with
Realized with general computing device, they can be concentrated on single computing device, or be distributed in multiple computing devices
On the network constituted, alternatively, the program code that they can be can perform with computing device be realized, it is thus possible to by it
Store and performed in the storage device by computing device, and in some cases, can be to be held different from order herein
They, are either fabricated to each integrated circuit modules or will be multiple in them by the shown or described step of row respectively
Module or step are fabricated to single integrated circuit module to realize.So, the embodiment of the present invention is not restricted to any specific hard
Part and software are combined.
The preferred embodiments of the present invention are the foregoing is only, are not intended to limit the invention, for the skill of this area
For art personnel, the embodiment of the present invention can have various modifications and variations.Within the spirit and principles of the invention, made
Any modification, equivalent substitution and improvements etc., should be included in the scope of the protection.
Claims (12)
1. a kind of recognition methods of tight sandstone reservoir microcrack development, this method includes：
Obtain rock sample in purpose stratum and enter mercury saturation degree under different capillary pressures；
Calculate respectively the capillary pressure logarithm and it is described enter mercury saturation degree logarithm；
According to the logarithm of the capillary pressure and it is described enter mercury saturation degree logarithm build scatter diagram；
Linear fit is carried out to the target data point in the scatter diagram, to obtain target fitting a straight line；
According to the slope of the target fitting a straight line, whether identification purpose stratum microcrack develops.
2. according to the method described in claim 1, it is characterised in that according to the logarithm of the capillary pressure and it is described enter mercury satisfy
Building scatter diagram with the logarithm of degree includes：
Using the logarithm of the capillary pressure as abscissa, using it is described enter mercury saturation degree logarithm as ordinate, build scatter diagram.
3. according to the method described in claim 1, it is characterised in that this method also includes：
Distribution to data point in the scatter diagram is analyzed, to obtain the regularity of distribution of data point in the scatter diagram；Its
In, the regularity of distribution of data point is as follows in the scatter diagram：
The distribution of data point is in the trend of one section or more than two sections different straight lines in the scatter diagram；
When the trend in more than two sections different straight lines, the slope of every section of straight line is differed.
4. the method according to claim 1 or 3, it is characterised in that the number of targets strong point is chosen by following operation：
Data point in the scatter diagram is grouped, the data point in same section of trends of straight line distribution is divided into one group；
On the basis of the origin of coordinates, that group data point near the origin of coordinates is chosen from the group of division as number of targets strong point.
5. according to the method described in claim 1, it is characterised in that according to the slope of the target fitting a straight line, identification is described
Purpose stratum microcrack whether develop including：
During slope≤1, the microcrack agensis of purpose stratum is determined；
Slope>When 1, the microcrack development of purpose stratum is determined.
6. according to the method described in claim 1, it is characterised in that the rock sample enters mercury saturation under different capillary pressures
Degree is to test to obtain by high-pressure mercury.
7. according to the method described in claim 1, it is characterised in that calculate respectively the capillary pressure logarithm and it is described enter
The logarithm of mercury saturation degree includes：
To it is described enter mercury saturation degree be corrected, to enter mercury saturation degree after being corrected；
The logarithm for entering mercury saturation degree after the logarithm of the capillary pressure, and the correction is calculated respectively.
8. a kind of identifying device of tight sand microcrack development, the device includes：
Acquiring unit, mercury saturation degree is entered for obtaining rock sample in purpose stratum under different capillary pressures；
Computing unit, for calculate respectively the capillary pressure logarithm and it is described enter mercury saturation degree logarithm；
Construction unit, for the logarithm according to the capillary pressure and it is described enter mercury saturation degree logarithm build scatter diagram；
Fitting unit, for carrying out linear fit to the target data point in the scatter diagram, to obtain target fitting a straight line；
Recognition unit, for the slope according to the target fitting a straight line, whether identification purpose stratum microcrack develops.
9. device according to claim 8, it is characterised in that the device also includes analytic unit, for the scatterplot
Data point in figure is analyzed, to obtain the regularity of distribution of data point in the scatter diagram；Wherein, data in the scatter diagram
The regularity of distribution of point is as follows：
The distribution of data point is in the trend of one section or more than two sections different straight lines in the scatter diagram；
When the trend in more than two sections different straight lines, the slope of every section of straight line is differed.
10. device according to claim 8, it is characterised in that the device also includes choosing unit, for according to following behaviour
Make to choose number of targets strong point：
Data point in the scatter diagram is grouped, the data point in same section of trends of straight line distribution is divided into one group；
On the basis of the origin of coordinates, that group data point near the origin of coordinates is chosen from the group of division as number of targets strong point.
11. device according to claim 8, it is characterised in that the recognition unit is used to be fitted directly according to the target
Whether the slope of line, identification purpose stratum microcrack develops：
During slope≤1, the microcrack agensis of purpose stratum is determined；
Slope>When 1, the microcrack development of purpose stratum is determined.
12. device according to claim 8, it is characterised in that the computing unit also includes：
Correct subelement, for it is described enter mercury saturation degree be corrected, to enter mercury saturation degree after being corrected；
Computation subunit, logarithm for calculating the capillary pressure respectively, and enter mercury saturation degree after the correction
Logarithm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710421072.7A CN107065033B (en) | 2017-06-07 | 2017-06-07 | A kind of recognition methods of tight sandstone reservoir microcrack development and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710421072.7A CN107065033B (en) | 2017-06-07 | 2017-06-07 | A kind of recognition methods of tight sandstone reservoir microcrack development and device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107065033A true CN107065033A (en) | 2017-08-18 |
| CN107065033B CN107065033B (en) | 2019-06-25 |
Family
ID=59616831
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710421072.7A Active CN107065033B (en) | 2017-06-07 | 2017-06-07 | A kind of recognition methods of tight sandstone reservoir microcrack development and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107065033B (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110320569A (en) * | 2018-03-30 | 2019-10-11 | 中国石油化工股份有限公司 | A kind of tight sandstone reservoir individual well fracture development quantification of intensities evaluation method |
| CN110567991A (en) * | 2018-10-29 | 2019-12-13 | 中国石油天然气股份有限公司 | Method and device for determining micro-crack development degree of tight sandstone reservoir |
| CN112682034A (en) * | 2020-12-04 | 2021-04-20 | 中国地质大学（北京） | Method and device for crack identification and dip angle characterization based on tight sandstone reservoir |
| CN113219553A (en) * | 2021-04-25 | 2021-08-06 | 中国石油大学(北京) | Method and device for predicting total organic carbon content of hydrocarbon source rock |
| CN113252711A (en) * | 2021-04-14 | 2021-08-13 | 成都理工大学 | Method for measuring gas-liquid ratio of fluid inclusion and sub-minerals |
| CN115506758A (en) * | 2021-06-04 | 2022-12-23 | 中国石油天然气股份有限公司 | Compact reservoir drainage pressure determination method, device, equipment and storage medium |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104458525A (en) * | 2013-09-13 | 2015-03-25 | 中国石油天然气股份有限公司 | Collection and processing method for characterizing micropore throat characteristics by conventional mercury injection curve |
| CN104634718A (en) * | 2015-03-05 | 2015-05-20 | 中国石油大学(华东) | Calibration method for representing dense sandstone pore size distribution by adopting nuclear magnetic resonance |
| CN105334149A (en) * | 2015-11-24 | 2016-02-17 | 中国石油大学(北京) | Micro-pore structure evaluation and reservoir classification method for tight reservoirs |
| CN106291704A (en) * | 2016-09-20 | 2017-01-04 | 中国地质大学（北京） | A kind of different scale fracture surface density prediction method |
-
2017
- 2017-06-07 CN CN201710421072.7A patent/CN107065033B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104458525A (en) * | 2013-09-13 | 2015-03-25 | 中国石油天然气股份有限公司 | Collection and processing method for characterizing micropore throat characteristics by conventional mercury injection curve |
| CN104634718A (en) * | 2015-03-05 | 2015-05-20 | 中国石油大学(华东) | Calibration method for representing dense sandstone pore size distribution by adopting nuclear magnetic resonance |
| CN105334149A (en) * | 2015-11-24 | 2016-02-17 | 中国石油大学(北京) | Micro-pore structure evaluation and reservoir classification method for tight reservoirs |
| CN106291704A (en) * | 2016-09-20 | 2017-01-04 | 中国地质大学（北京） | A kind of different scale fracture surface density prediction method |
Non-Patent Citations (4)
| Title |
|---|
| 尹燕义 等: "裂缝型储层裂缝发育程度分形描述方法", 《大庆石油学院学报》 * |
| 徐守余 等: "砂岩储层微观结构分形特征研究—以胜坨油田古近系沙河街组储层为例", 《天然气地球科学》 * |
| 文慧俭 等: "低孔低渗储层孔隙结构分形特征", 《大庆石油学院学报》 * |
| 郝明强: "微裂缝性特低渗透油藏渗流特征研究", 《中国优秀硕士学位论文全文数据库 工程科技I辑》 * |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110320569A (en) * | 2018-03-30 | 2019-10-11 | 中国石油化工股份有限公司 | A kind of tight sandstone reservoir individual well fracture development quantification of intensities evaluation method |
| CN110320569B (en) * | 2018-03-30 | 2021-07-27 | 中国石油化工股份有限公司 | Quantitative evaluation method for single well fracture development strength of compact sandstone reservoir |
| CN110567991A (en) * | 2018-10-29 | 2019-12-13 | 中国石油天然气股份有限公司 | Method and device for determining micro-crack development degree of tight sandstone reservoir |
| CN110567991B (en) * | 2018-10-29 | 2022-02-01 | 中国石油天然气股份有限公司 | Method and device for determining micro-crack development degree of tight sandstone reservoir |
| CN112682034A (en) * | 2020-12-04 | 2021-04-20 | 中国地质大学（北京） | Method and device for crack identification and dip angle characterization based on tight sandstone reservoir |
| CN113252711A (en) * | 2021-04-14 | 2021-08-13 | 成都理工大学 | Method for measuring gas-liquid ratio of fluid inclusion and sub-minerals |
| CN113252711B (en) * | 2021-04-14 | 2023-12-22 | 成都理工大学 | Determination method of gas-liquid ratio of fluid inclusion and sub-minerals |
| CN113219553A (en) * | 2021-04-25 | 2021-08-06 | 中国石油大学(北京) | Method and device for predicting total organic carbon content of hydrocarbon source rock |
| CN115506758A (en) * | 2021-06-04 | 2022-12-23 | 中国石油天然气股份有限公司 | Compact reservoir drainage pressure determination method, device, equipment and storage medium |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107065033B (en) | 2019-06-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107065033B (en) | A kind of recognition methods of tight sandstone reservoir microcrack development and device | |
| Xiao et al. | Impacts of clay on pore structure, storage and percolation of tight sandstones from the Songliao Basin, China: implications for genetic classification of tight sandstone reservoirs | |
| Wenlian et al. | Evaluation of the stress sensitivity in tight reservoirs | |
| CN110231272B (en) | Compact sandstone pore diameter and nuclear magnetic resonance T2Method and system for determining value conversion relation | |
| CN109061765B (en) | Trap evaluation method for heterogeneous thin sandstone interbed reservoir | |
| CN103278436B (en) | Quantitative characterization method of low penetration double-medium sandstone oil reservoir microscopic aperture structure | |
| CN105160414B (en) | Predict the method and device of full oil reservoir producing region type | |
| CN104750884B (en) | Shale rich accumulation of oil and gas index quantitative evaluation method based on multifactor nonlinear regression | |
| Xiao et al. | Comparative study of models for predicting permeability from nuclear magnetic resonance (NMR) logs in two Chinese tight sandstone reservoirs | |
| CN104989386B (en) | A kind of generation method of fine and close oily property identification method and plate | |
| CN105525917B (en) | The method for identifying fluid type in the method and identification reservoir of reservoir | |
| CN106772608B (en) | The elastic impedance and Generalized Fluid factor-analysis approach of equivalent aperture gap fracture medium | |
| CN106355571B (en) | A kind of determination method and device of dolostone reservoirs quality | |
| Dongqi et al. | Fine classification of ultra-low permeability reservoirs around the Placanticline of Daqing oilfield (PR of China) | |
| CN110487693A (en) | A kind of method of determining mud shale different type porosity | |
| CN105447762A (en) | Calculation method for low permeability reservoir flooding information of fluid replacement | |
| CN111027818A (en) | Shale oil classification evaluation method | |
| CN106897531A (en) | A kind of method for quantitatively evaluating of hyposmosis limestone reservoir permeability | |
| CN105158802A (en) | Logging quantitative recognition method for gravity flow sediments in down-warped lake basin | |
| CN109298464A (en) | Tight sandstone reservoir Diagenetic Facies Logging Identification Method and device | |
| CN110208874B (en) | Method for identifying effective reservoir of tight sandstone reservoir | |
| CN112145165A (en) | Dynamic and static permeability conversion method for micro-crack-pore type reservoir | |
| CN106524998B (en) | Method based on three-dimensional laser scanning technique measurement tunnel threadiness exposure structural plane | |
| CN106156456A (en) | Sand-conglomerate body invalid reservoir subtraction method | |
| CN104514553A (en) | Recognition method of gas reservoir in lithic sandstone layer and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |