CN103867194A - Well logging characterization method, well drilling layer section selecting method and well drilling layer section selecting device of a sand body structure - Google Patents

Abstract

The invention provides a well logging characterization method, a well drilling layer section selecting method and a well drilling layer section selecting device of a sand body structure. The well drilling layer section selecting method comprises the steps of S1, selecting sampling point data of a natural gamma-ray well logging curve in a needed processing layer section and calculating a smooth degree GS of the natural gamma-ray well logging curve; S2, calculating an average value of shale contents in the processing layer section; S3, building a formula, which is as shown in the attached drawing, of well logging characterization parameters Pss of the sand body structure; S4, comparing the sand body structure differences of different processing layer sections according to Pss values, and selecting a processing section in a minimum Pss value as an optimized layer section; S5, carrying out optimization and well drilling development on an oil gas enrichment area of the sand structure according to the optimized layer section. The well logging characterization method, the well drilling layer section selecting method and the well drilling layer section selecting device of the sand body structure, provided by the invention can be used for quantitatively comparing the differences of reservoir sand body structures, have the advantages of simpleness, intuition, high distinguishing degree, good reliability and the like, and are capable of supplying technical support to the optimization and the well drilling development of the oil gas enrichment area in densification oil gas.

Description

A kind of well logging characterizing method of sand body structure and the system of selection of drilling well interval and device

Technical field

The present invention relates to logging evaluation technical field in oil-gas exploration, be specifically related to a kind of well logging characterizing method and the system of selection of drilling well interval and device of sand body structure.

Background technology

In lithological pool, oil and gas reservoir sand body refers to the sand body of oil-containing in subsurface reservoir, is made up of a lot of irregular sand bodies, is the minimum oil-containing unit of oilbearing stratum, is also the base unit of controlling oil, water sport.Under different depositional environment conditions, sandstone reservoir architectural difference is larger, and the difference of good differentiation sandstone reservoir structure, has important function to Comprehensive Evaluation of Reservoirs and developmental research.

In petroleum exploration domain, conventional natural gamma rays logging method carrys out the sand body structure of Research on Oil gas reservoir at present.The method is in the natural gamma radioactivity intensity of surveying borehole measurement Different Strata with gamma-ray detector, gather, record well-log information and calculating and plotting goes out log, be Natural Gamma-ray Logging Curves, utilize Natural Gamma-ray Logging Curves identification lithology and divide reservoir, calculating shale content.From the form of described Natural Gamma-ray Logging Curves, comprise amplitude and the shape of Natural Gamma-ray Logging Curves, can qualitatively distinguish the sand body structure of oil and gas reservoir.For example, amplitude is one of key character of form of logs, and amplitude size can reflect that the Sediment Characteristics such as sedimental granularity, sorting and shale content change.The shape of Natural Gamma-ray Logging Curves comprises that box-shaped, bell, infundibulate, straight shape etc. also can reflect the sedimentary facies of reservoir and the feature of sand body structure.As box-shaped, reflection be the result of the stable and rapid accumulation of the in plentiful supply and hydrodynamic condition in thing source, as the distributary channel of delta etc.; Bell, reflection be that hydrodynamic force weakens gradually and thing source supply reduces, as meandering stream point bar deposit etc., the positive grain order architectural feature in the sedimentary sequence of curve reflection river course lateral migration and river course.In addition, the smooth degree of various pattern curves also can reflect the difference of sandstone reservoir architectural feature.As abundant in smooth Natural Gamma-ray Logging Curves representative source, hydrodynamism is strong; Dentation represents the stack of intermittent deposition, as alluvial fan and braided channel deposition.

Sand body structure that can qualitative analysis reservoir according to the amplitude of Natural Gamma-ray Logging Curves and shape, but owing to lacking the embodiments parameter of well logging, the method can not be carried out quantitative analysis to the different interval sand body structures of individual well or many wells, its subjective impact is large, judged result error is larger, can not carry out to the different intervals of individual well or many wells the plane distribution difference contrast of quantitative contrast selection and sand body structure, the further research of sandstone reservoir structure and relationship between productivity aspect and " dessert " region (rich accumulation of oil and gas region) of fine and close oil gas and the selection of drilling well range of profitability are affected.

Summary of the invention

The object of the invention is to provide a kind of well logging characterizing method and the system of selection of drilling well interval and device of sand body structure, utilize the smooth degree of shale content and Natural Gamma-ray Logging Curves in well-log information to carry out the fine and close oil and gas reservoir sand body of quantitatively characterizing structure, realize the quantitative contrast of individual well or many wells sand body structure and preferably.

The drilling well interval system of selection of a kind of sand body structure provided by the invention, its implementation procedure comprises following treatment step:

S1: the Natural Gamma-ray Logging Curves sampling number of choosing institute's layer to be addressed in well according to and calculate the smooth degree GS of its Natural Gamma-ray Logging Curves;

S2: the average that calculates shale content in described processing interval

S3: the well logging characterization parameter Pss that sets up sand body structure according to the average of shale content and the smooth degree of its corresponding Natural Gamma-ray Logging Curves in described processing interval; The expression formula of setting up the well logging characterization parameter Pss of sand body structure described in it is:

$\mathrm{Pss}=\mathrm{GS}\×\stackrel{\‾}{V_{\mathrm{sh}}}$

S4: according to the sand body architectural difference of the well logging characterization parameter Pss value contrast different disposal interval of the bedding section that do not exist together, select processing interval that Pss value is little as preferred interval;

S5: the rich accumulation of oil and gas region of carrying out sand body structure according to the preferred interval of described selection is preferably developed with drilling well.

The drilling well interval system of selection of a kind of sand body structure described above, its preferred version is, the smooth degree GS that calculates Natural Gamma-ray Logging Curves described in S1 comprises following treatment step:

S101: the variance S of natural gamma value in the Natural Gamma-ray Logging Curves of choosing described in calculating ²;

S102: the variation γ of natural gamma value (h) in the Natural Gamma-ray Logging Curves of choosing described in calculating;

S103: the smooth degree GS of the Natural Gamma-ray Logging Curves of choosing described in calculating, its design formulas is:

$\mathrm{GS}=\sqrt{\mathrm{\&Sigma;\&gamma;}\left(h\right)+{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="HDA0000466099620000021.png,HDA0000466099620000022.png"\; state="\{\{state\}\}">S</figure-callout>}}^2}$

Wherein, ∑ γ (h) for h gets corresponding γ (h) value sum when different natural gamma value sampling interval value.

The drilling well interval system of selection of a kind of sand body structure described above, its preferred version is, calculate described ∑ γ (h) for h gets when different natural gamma value sampling interval value the concrete grammar of corresponding γ (h) value sum be:

H is value 1 and the addition of 2 o'clock corresponding γ (h) values respectively.

The drilling well interval system of selection of a kind of sand body structure described above, its preferred version is, the average of shale content in described computing interval comprise following treatment step:

S201: calculate each sampled point natural gamma in described processing interval and change relative value SH;

S202: the shale content V that calculates each sampled point in described processing interval _sh, its design formulas is:

$V_{\mathrm{sh}}=\frac{2^{\mathrm{GCUR}\&times;\mathrm{SH}}-1}{2^{\mathrm{GCUR}}-1}\&times;100\%$

In above formula, GCUR is Xi Erqi index;

S203: calculate all sampled point shale content V in described processing interval _shaverage

The drilling well interval selecting party device of a kind of sand body structure described above, its preferred version is, this device comprises Natural Gamma-ray Logging Curves GS computing module, shale content computing module, Pss computing module, favourable interval preferred module, rich accumulation of oil and gas region preferred module, wherein:

Described gamma ray curve GS computing module, for the Natural Gamma-ray Logging Curves sampling number of choosing well institute layer to be addressed according to and calculate the smooth degree GS of its Natural Gamma-ray Logging Curves;

Described shale content computing module, for calculating the average of shale content in described processing interval

Described Pss computing module, for setting up the well logging characterization parameter Pss of sand body structure according to the average of shale content and the smooth degree of its corresponding Natural Gamma-ray Logging Curves in described processing interval; Described in it, the calculation expression of sand body structure well logging characterization parameter Pss is:

$\mathrm{Pss}=\mathrm{GS}\&times;\stackrel{\&OverBar;}{V_{\mathrm{sh}}}$

Described favourable interval preferred module, for according to the sand body architectural difference of the well logging characterization parameter Pss value contrast different disposal interval of the bedding section that do not exist together, the little processing interval of selection Pss value is as preferred interval;

Described rich accumulation of oil and gas region preferred module, preferably develops with drilling well for the rich accumulation of oil and gas region of carrying out sand body structure according to the preferred interval of described selection.

The drilling well interval selecting party device of a kind of sand body structure described above, its preferred version is, described GR curve GS computing module comprises variance computing module, variation computing module, GS computing module, wherein:

Described variance computing module, for the variance S of the Natural Gamma-ray Logging Curves natural gamma value chosen described in calculating ²;

Described variation computing module, for the variation γ (h) of the Natural Gamma-ray Logging Curves natural gamma value chosen described in calculating;

Described GS computing module, for the smooth degree GS of the Natural Gamma-ray Logging Curves chosen described in calculating, its design formulas is:

$\mathrm{GS}==\sqrt{\mathrm{\&Sigma;\&gamma;}\left(h\right)+{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="HDA0000466099620000021.png,HDA0000466099620000022.png"\; state="\{\{state\}\}">S</figure-callout>}}^2}$

Wherein, for h gets, the different sampling intervals are worth corresponding γ (h) value sum to ∑ γ (h).

The drilling well interval selecting party device of a kind of sand body structure described above, its preferred version is that described variation computing module comprises sampling interval setting module, is used to variation computing module that different sampling interval value h is set.

The drilling well interval selecting party device of a kind of sand body structure described above, its preferred version is, described shale content computing module comprises that GR changes relative value computing module, sampled point shale content computing module, shale content mean value calculation module, wherein:

Described GR changes relative value computing module, changes relative value SH for calculating each sampled point natural gamma in described processing interval;

Described sampled point shale content computing module, for calculating the shale content V of each sampled point in described processing interval _sh, its design formulas is:

$V_{\mathrm{sh}}=\frac{2^{\mathrm{GCUR}\&times;\mathrm{SH}}-1}{2^{\mathrm{GCUR}}-1}\&times;100\%$

In above formula, GCUR is Xi Erqi index;

Described shale content mean value calculation module, for calculating all sampled point shale content V in described processing interval _shaverage

The well logging characterizing method that the invention provides a kind of sand body structure, comprises following treatment step:

S110: the Natural Gamma-ray Logging Curves sampling number of choosing institute's layer to be addressed according to and calculate the smooth degree GS of its Natural Gamma-ray Logging Curves;

S120: the average that calculates shale content in described processing interval

S130: the well logging characterization parameter Pss that sets up sand body structure according to the average of shale content and the smooth degree of its corresponding Natural Gamma-ray Logging Curves in described processing interval; The expression formula of setting up the well logging characterization parameter Pss of sand body structure described in it is:

$\mathrm{Pss}=\mathrm{GS}\&times;\stackrel{\&OverBar;}{V_{\mathrm{sh}}}.$

The well logging characterizing method of a kind of sand body structure provided by the invention and the system of selection of drilling well interval and device, according to the relation of the smooth degree of actual Natural Gamma-ray Logging Curves, reservoir shale content and sandstone reservoir structure, set up a kind of can quantitatively characterizing sandstone reservoir structure and the drilling well method and apparatus of selecting interval to select.The inventive method connects the shale content of the concrete sampled point numerical value of the characteristic of sandstone reservoir structure and Natural Gamma-ray Logging Curves and this section of reservoir, carries out quantization signifying.According to the quantization signifying of concrete different interval sand body structures, can carry out individual well or the contrast of many wells, the favorable oil/gas interval that carries out individual well or many wells is preferred, and preferred interval is carried out to drilling well exploitation.Pass through the method, Using Conventional Logs can be calculated to the well logging characterization parameter that obtains tight sand oil and gas reservoir sand body structure, explain the sandstone reservoir structure types of different wells with different numerical value, loaded down with trivial details amplitude and the method for shape recognition are simplified, can identify more intuitively individual well or many wells oil and gas reservoir sand body structure and quantitatively characterizing sand body structure, there is the advantages such as simple, directly perceived, discrimination is high, good reliability, there is obvious practical application effect.

Accompanying drawing explanation

Fig. 1 is the flow chart of the drilling well interval system of selection of a kind of sand body structure of providing of the embodiment of the present invention 1;

Fig. 2 utilizes the present embodiment 1 sandstone reservoir structural calculation result comparison diagram to two mouthfuls of wells respectively;

Fig. 3 is the modular structure schematic diagram of the drilling well interval selecting arrangement of a kind of sand body structure of providing of the embodiment of the present invention 1;

Fig. 4 is the modular structure schematic diagram of the GR curve GS computing module that provides of the embodiment of the present invention 2;

Fig. 5 is the variation computing module structural representation that the embodiment of the present invention 2 provides;

Fig. 6 is the modular structure schematic diagram of the shale content computing module that provides of the embodiment of the present invention 2;

Fig. 7 be utilize sand body structural characterization parameter Pss that the present embodiment 3 methods obtain and formation testing production capacity be related to schematic diagram.

The specific embodiment

In order to make those skilled in the art person understand better the technical scheme in the application, below in conjunction with the accompanying drawing in the embodiment of the present application, the technical scheme in the embodiment of the present application is clearly and completely described.Obviously, described embodiment is only the application's part embodiment, rather than whole embodiment.Based on the embodiment in the application, those of ordinary skills, not making all other embodiment that obtain under creative work prerequisite, should belong to the scope of protection of the invention.

Embodiment 1

Embodiment 1 is the drilling well interval system of selection of a kind of sand body structure provided by the invention.Fig. 1 is the flow chart of the drilling well interval system of selection of a kind of sand body structure provided by the invention.As shown in Figure 1, a kind of drilling well interval system of selection of sand body structure, its embodiment comprises following treatment step:

S1: the Natural Gamma-ray Logging Curves sampling number of choosing institute's layer to be addressed in well according to and calculate the smooth degree GS of its Natural Gamma-ray Logging Curves.

First, survey and obtain well-log information and draw out Natural Gamma-ray Logging Curves in the well logging of target area with gamma-ray detector, select the Natural Gamma-ray Logging Curves of institute's layer to be addressed.

Secondly, calculate the smooth degree of selected Natural Gamma-ray Logging Curves.Conventionally, the smooth degree of described Natural Gamma-ray Logging Curves can adopt on curve the overall fluctuation of natural gamma value and the size of natural gamma sawtooth and how much represent, also can adopt according to demand other define method to represent.In the present embodiment 1, adopt the smooth degree that the combination of the variance of institute's layer to be addressed natural gamma value and variation is defined as to institute's layer to be addressed Natural Gamma-ray Logging Curves.Its concrete operating process comprises following treatment step:

S101: the variance S of natural gamma value in the Natural Gamma-ray Logging Curves of choosing described in calculating ².

In data statistics, variance S ²can reflect the size of data entirety fluctuation.Therefore, the present embodiment 1 adopts the variance S of natural gamma value in selected processing interval Natural Gamma-ray Logging Curves ²represent its overall fluctuation, its design formulas is:

${\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="HDA0000466099620000021.png,HDA0000466099620000022.png"\; state="\{\{state\}\}">S</figure-callout>}}^2=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{(x_i-\stackrel{\&OverBar;}{x})}^2$

In above formula, x _ifor the natural gamma value of a certain depth point in described processing interval,

for the average of natural gamma value in described processing interval.N is the number of natural gamma value in described processing interval.

S102: the variation γ of natural gamma value (h) in the Natural Gamma-ray Logging Curves of choosing described in calculating.

In Natural Gamma-ray Logging Curves sawtooth more greatly, more place, the fluctuation of this place's curve is larger; On the contrary, the place that sawtooth is less, fewer, the fluctuation of curve is just less herein.And variogram can reflect the size of data localised waving preferably, the variogram γ (h) that therefore the present embodiment 1 is introduced in geostatistics represents its localised waving, and its design formulas is:

$\mathrm{\&gamma;}\left(h\right)=\frac{1}{2N\left(h\right)}\underset{i=1}{\overset{N\left(h\right)}{\mathrm{\&Sigma;}}}{(x_i-x_{i+h})}^2$

In above formula, h calculates the natural gamma value sampling interval that variation is used, and N (h) is to be that the natural gamma data of h are to (x in the sampling interval _i, x _i+h) number.In the time calculating the variation sum ∑ γ (h) of natural gamma value, h can get different values and obtain multiple different γ (h).

S103: the smooth degree GS of the Natural Gamma-ray Logging Curves of choosing described in calculating.

The size of variance reflection data entirety fluctuation, the size of variation reflection data localised waving, gets both root sum squares and is defined as variation variance root GS, is used for processing described in concentrated expression the smooth degree of Natural Gamma-ray Logging Curves in interval.Its design formulas is:

wherein, for h gets, the different natural gamma value sampling intervals are worth corresponding γ (h) value sum to ∑ γ (h).In the present embodiment 1, h can calculate value 1 and 2 respectively corresponding γ (h) and is added and obtains ∑ γ (h), therefore smooth degree GS design formulas can be also described in the present embodiment 1:

S2: the average that calculates shale content in described processing interval

The computational methods of described shale content can adopt Relative ratio method, also can adopt the additive method including the computational methods such as Schlumberger company.In the present embodiment 1, adopt Relative ratio method to calculate the average of described processing interval reservoir shale content.Its concrete operating process comprises following treatment step:

S201: calculate each sampled point natural gamma in described processing interval and change relative value SH.

Get pure shale gamma ray log value GRmax and clean sandstone gamma ray log value GRmin in selected processing interval, calculate according to the natural gamma value GR of selected each sampled point of processing interval the natural gamma that its shale content causes and change relative value SH(also referred to as shaliness index):

$\mathrm{SH}=\frac{\mathrm{GR}-\mathrm{GR}\min }{\mathrm{GR}\max -\mathrm{GR}\min }$

In above formula, the natural gamma value that GR is a certain sampled point, pure shale gamma ray log value in the selected processing interval of GRmax, clean sandstone gamma ray log value in the selected processing interval of GRmin.GRmax is a pair of and selected interval geographical position physical quantity relevant with stratum age with GRmin, and in the time selecting the interval of required processing, these two values can be defined as certain concrete certain value according to on-site actual situations.

S202: the shale content Vsh that calculates each sampled point in described processing interval.

Calculate the shale content Vsh of sampled point in described processing interval according to the above-mentioned natural gamma variation relative value calculating:

$V_{\mathrm{sh}}=\frac{2^{\mathrm{GCUR}\&times;\mathrm{SH}}-1}{2^{\mathrm{GCUR}}-1}\&times;100\%$

In above formula, GCUR is Xi Erqi index, and the size of this value is relevant with stratum age.Conventionally in tertiary stratum, this value gets 3.7; In old stratum, get 2.

S203: the average that calculates described processing interval reservoir shale content

Calculate the average of described processing interval reservoir shale content

$\stackrel{\&OverBar;}{V_{\mathrm{sh}}}=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{\left(V_{\mathrm{sh}}\right)}_i$

S3: the well logging characterization parameter Pss that sets up sand body structure according to the average of shale content and the smooth degree of Natural Gamma-ray Logging Curves in described processing interval.

In the present embodiment 1 according to the average of described shale content

set up the characterization parameter Pss of sandstone reservoir structure with the product of the smooth degree GS of Natural Gamma-ray Logging Curves, its expression formula is:

$\mathrm{Pss}=\mathrm{GS}\&times;\stackrel{\&OverBar;}{V_{\mathrm{sh}}}$

S4: according to the sand body structure of the well logging characterization parameter Pss value contrast different disposal interval of the bedding section that do not exist together, select processing interval that Pss value is little as preferred interval.

S5: the rich accumulation of oil and gas region of carrying out sand body structure according to the preferred interval of described selection is preferably developed with drilling well.

Under normal circumstances, interval Natural Gamma-ray Logging Curves is more smooth, and GS value is less, the non-homogeneity that this Reservoir Section is described is more weak, sandstone reservoir structure is better, and the meaning of drilling well exploitation is larger, belongs to preferred interval (preferably carrying out the interval of drilling well exploitation in individual well or many wells); On the contrary, its corresponding shale content is higher, and sandstone reservoir structure is poorer, and the Pss value obtaining is also larger, and the meaning of its drilling well exploitation is less.Can its corresponding sand body structures of Pss value of different sizes be mapped according to field experiment repeatedly, obtain the form that contrasts of Pss value and sandstone reservoir structure.Characterization parameter Pss in the present embodiment 1, can quantitatively the feature of sandstone reservoir structure be reflected, for the Comprehensive Evaluation of Reservoirs such as follow-up many Jingyan County are studied carefully, the analysis of manufacturing capability and fine and close oil gas " dessert " (rich accumulation of oil and gas region) preferably provide good foundation with drilling well exploitation.

The drilling well interval system of selection of a kind of sand body structure that the embodiment of the present invention 1 provides, can be by conventional gamma ray log data through calculating the well logging characterization parameter that obtains tight sand oil and gas reservoir sand body structure by the method, can determine sand body structure types, simplified loaded down with trivial details amplitude and the method for shape recognition, quantitative contrast is selected large oil and gas reservoir sand body structure interval and the quantitatively characterizing sand body structure of drilling well exploitation meaning more intuitively.

Fig. 2 utilizes the present embodiment 1 method respectively the different intervals of two mouthfuls of wells to be carried out to sandstone reservoir structural calculation result comparison diagram.As shown in Figure 2, first choose the interval of required processing, wherein A1 well sandstone reservoir section is 1784.625 to 1806.625 meters, and GR log sampled point is 176.A2 well sandstone reservoir section is 1812.125 to 1829.25 meters, and GR log sampled point is 137.Calculate the smooth degree of A1 well and A2 well sandstone reservoir section Natural Gamma-ray Logging Curves according to step S1.Calculate the variance S of GR curve data point in required layer of sand according to step S101 ², the variance S of A1 well sandstone reservoir section ²be the variance S of 184.8, A2 well sandstone reservoir section ²be 663.2; Calculate the variation of natural gamma value in the Natural Gamma-ray Logging Curves under the different sampling intervals according to step S102.In the present embodiment 1, h gets respectively 1 and 2, N (1)=175, N (2)=88 in corresponding A1 well, N in A2 well (1)=136, N (2)=68.The γ (1) that substitution step S102 variogram obtains respectively A1 well sandstone reservoir section is that 22.8, γ (2) is that the γ (1) of 76.59, A2 well sandstone reservoir section is that 21.917, γ (2) is 98.185.The GS that calculates respectively A1 well sandstone reservoir section according to the above results is that the GS of 16.86, A2 well sandstone reservoir section is 28.09.

Secondly, in step S2, calculate respectively in A1 well sandstone reservoir section according to the natural gamma value GR of each sampled point in selected processing interval

be 16, the % of unit, in A2 well sandstone reservoir section

be 18, the % of unit.In the present embodiment 1, GCUR value is 2.

Then, utilize expression formula in step S3 to set up and calculate sandstone reservoir structural parameter P ss, and the Pss value that calculates A1 well sandstone reservoir section is that the Pss value of 269.76, A2 well sandstone reservoir section is 505.7.

Then, contrast its sand body architectural difference according to the well logging characterization parameter of A1 well and A2 well interval, the optimizing well section that the well that selection Pss is little is developed as drilling well.The Pss value of A1 well sandstone reservoir section is less by 235.94 than the Pss value of A2 well sandstone reservoir section, and a little less than illustrating that non-homogeneity in A1 well sandstone reservoir section is than A2 well, sandstone reservoir structure is better than A2 well, is the preferred interval of drilling well exploitation therefore can select A1 well.

Last in the situation that other drilling well factor gaps are little, select A1 well to carry out drilling well exploitation.

According to the distribution of Pss value, can analyze and show that A1 well sandstone reservoir structure is block sand body simultaneously, A2 well sandstone reservoir structure is mutual laminar sand.Application the inventive method has realized the quantitatively characterizing to sandstone reservoir structure types, and to the judgement of sand body structure have simply, directly perceived, the advantage such as discrimination is high, good reliability, energy applications well, in many wells quantitative contrast, has obvious practical application effect.

Embodiment 2

Embodiment 2 is a kind of sand body structure drilling well interval selecting arrangements that the present invention provides according to the drilling well interval system of selection of a kind of sand body structure described in embodiment 1, can select the better interval of sand body structure and carry out drilling well exploitation as preferred interval.Fig. 3 is the modular structure schematic diagram of the drilling well interval selecting arrangement of described a kind of sand body structure.As shown in Figure 3, the well logging sign of described a kind of sand body structure and drilling well interval selecting arrangement comprise GR curve GS computing module 1, shale content computing module 2, Pss computing module 3, favourable interval preferred module 4, rich accumulation of oil and gas region preferred module 5, wherein:

Described GR curve GS computing module 1, can for the Natural Gamma-ray Logging Curves sampling number of choosing institute's layer to be addressed in well according to and calculate the smooth degree GS of its Natural Gamma-ray Logging Curves;

Described shale content computing module 2, can be for calculating the average of shale content in described processing interval

Described Pss computing module 3, can be for setting up the well logging characterization parameter Pss of sand body structure according to the average of shale content and the smooth degree of its corresponding Natural Gamma-ray Logging Curves in described processing interval; Described in it, the calculation expression of sand body structure well logging characterization parameter Pss is:

$\mathrm{Pss}=\mathrm{Gs}\&times;\stackrel{\&OverBar;}{V_{\mathrm{sh}}}$

Described preferred module 4, can be for according to the sand body architectural difference of the well logging characterization parameter Pss value contrast different disposal interval of the bedding section that do not exist together, and the little processing interval of selection Pss value is as preferred interval;

Described rich accumulation of oil and gas region preferred module 5, can preferably develop with drilling well for the rich accumulation of oil and gas region of carrying out sand body structure according to the preferred interval of described selection.

Fig. 4 is the modular structure schematic diagram of the GR curve GS computing module that provides of the embodiment of the present invention 2.As shown in Figure 4, described GR curve GS computing module 1 can comprise variance computing module 101, variation computing module 102, GS computing module 103.Wherein:

Described variance computing module 101, can be for the variance S of natural gamma value in the Natural Gamma-ray Logging Curves of choosing described in calculating ²;

Described variation computing module 102, can be for the variation γ (h) of natural gamma value in the Natural Gamma-ray Logging Curves of choosing described in calculating;

Described GS computing module 103, can be for the smooth degree GS of the Natural Gamma-ray Logging Curves chosen described in calculating, and its design formulas is:

$\mathrm{GS}=\sqrt{\mathrm{\&Sigma;\&gamma;}\left(h\right)+{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="HDA0000466099620000021.png,HDA0000466099620000022.png"\; state="\{\{state\}\}">S</figure-callout>}}^2}$

Wherein, for h gets, the different sampling intervals are worth corresponding γ (h) value sum to ∑ γ (h).

As shown in Figure 5, variation computing module 102 described above can comprise sampling interval setting module 1021, can be used to variation computing module 102 that different sampling interval value h is set.

Fig. 6 is the modular structure schematic diagram of the shale content computing module 2 that provides of the embodiment of the present invention 2.As shown in Figure 6, described shale content computing module 2 can comprise that GR changes relative value computing module 201, sampled point shale content computing module 202, shale content mean value calculation module 203.Wherein:

Described GR changes relative value computing module 201, can change relative value SH for calculating each sampled point natural gamma in described processing interval;

Described sampled point shale content computing module 202, can be for calculating the shale content Vsh of each sampled point in described processing interval, and its design formulas is:

$V_{\mathrm{sh}}=\frac{2^{\mathrm{GCUR}\&times;\mathrm{SH}}-1}{2^{\mathrm{GCUR}}-1}\&times;100\%$

In above formula, GCUR is Xi Erqi index;

Described shale content mean value calculation module 203, can be for calculating all sampled point shale content V in described processing interval _shaverage

Embodiment 3 is well logging characterizing methods of a kind of sand body structure provided by the invention, the method by the feature quantitative expression of sandstone reservoir structure out, can judge the corresponding structure types of sandstone reservoir structure according to its concrete numerical value, for identification and the contrast of real well medium sand body structure provide convenience.The method comprises following treatment step:

S110: the Natural Gamma-ray Logging Curves sampling number of choosing institute's layer to be addressed according to and calculate the smooth degree GS of its Natural Gamma-ray Logging Curves;

S120: the average that calculates shale content in described processing interval

S130: the well logging characterization parameter Pss that sets up sand body structure according to the average of shale content and the smooth degree of its corresponding Natural Gamma-ray Logging Curves in described processing interval; The expression formula of setting up the well logging characterization parameter Pss of sand body structure described in it is:

$\mathrm{Pss}=\mathrm{GS}\&times;\stackrel{\&OverBar;}{V_{\mathrm{sh}}}.$

Fig. 7 utilizes sand body structural characterization parameter Pss that the embodiment of the present invention 3 methods obtain and production capacity (every meter of daily output) the relation Butut of formation testing.As can be seen from Figure 7, Pss is less for sandstone reservoir structural characterization parameter, and corresponding formation testing production capacity is higher.Through on-the-spot oil field examples prove, the definite sand body structural characterization parameter Pss of fine and close reservoir productivity and the present invention has good corresponding relation, for selection and the exploitation of oil well provide reliable technical support.

As can be seen from the above-described embodiment, the well logging characterizing method of a kind of sand body structure provided by the invention and the system of selection of drilling well interval and device can carry out grading evaluation to fine and close reservoir productivity preferably, through the result of calculation check of the many mouthfuls of wells in scene, have that discrimination is high, the feature of reliable results, for exploration and development and the dessert of fine and close oil gas preferably select with drilling well interval the technical support that provides strong.

Claims (9)

1. a drilling well interval system of selection for sand body structure, is characterized in that, comprises following treatment step:

S1: the Natural Gamma-ray Logging Curves sampling number of choosing institute's layer to be addressed in well according to and calculate the smooth degree GS of its Natural Gamma-ray Logging Curves;

S2: the average that calculates shale content in described processing interval

S3: the well logging characterization parameter Pss that sets up sand body structure according to the average of shale content and the smooth degree of its corresponding Natural Gamma-ray Logging Curves in described processing interval; The expression formula of setting up the well logging characterization parameter Pss of sand body structure described in it is:

$\mathrm{Pss}=\mathrm{GS}\&times;\stackrel{\&OverBar;}{V_{\mathrm{sh}}}$

S4: according to the sand body architectural difference of the well logging characterization parameter Pss value contrast different disposal interval of the bedding section that do not exist together, select processing interval that Pss value is little as preferred interval;

S5: the rich accumulation of oil and gas region of carrying out sand body structure according to the preferred interval of described selection is preferably developed with drilling well.

2. the drilling well interval system of selection of a kind of sand body structure as claimed in claim 1, is characterized in that, the smooth degree GS that calculates Natural Gamma-ray Logging Curves described in S1 comprises following treatment step:

S101: the variance S of natural gamma value in the Natural Gamma-ray Logging Curves of choosing described in calculating ²;

S102: the variation γ of natural gamma value (h) in the Natural Gamma-ray Logging Curves of choosing described in calculating;

S103: the smooth degree GS of the Natural Gamma-ray Logging Curves of choosing described in calculating, its design formulas is:

Wherein, ∑ γ (h) for h gets corresponding γ (h) value sum when different natural gamma value sampling interval value.

3. the drilling well interval system of selection of a kind of sand body structure as claimed in claim 2, is characterized in that, calculate described ∑ γ (h) for h gets when different natural gamma value sampling interval value the concrete grammar of corresponding γ (h) value sum be:

H is value 1 and the addition of 2 o'clock corresponding γ (h) values respectively.

4. the drilling well interval system of selection of a kind of sand body structure as claimed in claim 1, is characterized in that, the average of shale content in described computing interval

comprise following treatment step:

S201: calculate each sampled point natural gamma in described processing interval and change relative value SH;

S202: the shale content V that calculates each sampled point in described processing interval _sh, its design formulas is:

$V_{\mathrm{sh}}=\frac{2^{\mathrm{GCUR}\&times;\mathrm{SH}}-1}{2^{\mathrm{GCUR}}-1}\&times;100\%$

In above formula, GCUR is Xi Erqi index;

S203: calculate all sampled point shale content V in described processing interval _shaverage

5. a drilling well interval selecting arrangement for sand body structure, is characterized in that, this device comprises Natural Gamma-ray Logging Curves GS computing module, shale content computing module, Pss computing module, favourable interval preferred module, rich accumulation of oil and gas region preferred module, wherein:

Described gamma ray curve GS computing module, for the Natural Gamma-ray Logging Curves sampling number of choosing well institute layer to be addressed according to and calculate the smooth degree GS of its Natural Gamma-ray Logging Curves;

Described shale content computing module, for calculating the average of shale content in described processing interval

Described Pss computing module, for setting up the well logging characterization parameter Pss of sand body structure according to the average of shale content and the smooth degree of its corresponding Natural Gamma-ray Logging Curves in described processing interval; Described in it, the calculation expression of sand body structure well logging characterization parameter Pss is:

$\mathrm{Pss}=\mathrm{GS}\&times;\stackrel{\&OverBar;}{V_{\mathrm{sh}}}$

Described favourable interval preferred module, for according to the sand body architectural difference of the well logging characterization parameter Pss value contrast different disposal interval of the bedding section that do not exist together, the little processing interval of selection Pss value is as preferred interval;

Described rich accumulation of oil and gas region preferred module, preferably develops with drilling well for the rich accumulation of oil and gas region of carrying out sand body structure according to the preferred interval of described selection.

6. the drilling well interval selecting arrangement of a kind of sand body structure as claimed in claim 5, is characterized in that, described gamma ray curve GS computing module comprises variance computing module, variation computing module, GS computing module, wherein:

Described variance computing module, for the variance S of the Natural Gamma-ray Logging Curves natural gamma value chosen described in calculating ²;

Described variation computing module, for the variation γ (h) of the Natural Gamma-ray Logging Curves natural gamma value chosen described in calculating;

Described GS computing module, for the smooth degree GS of the Natural Gamma-ray Logging Curves chosen described in calculating, its design formulas is:

$\mathrm{GS}=\sqrt{\mathrm{\&Sigma;\&gamma;}\left(h\right)+S^2}$

Wherein, for h gets, the different sampling intervals are worth corresponding γ (h) value sum to ∑ γ (h).

7. the drilling well interval selecting arrangement of a kind of sand body structure as claimed in claim 6, is characterized in that, described variation computing module comprises sampling interval setting module, is used to variation computing module that different sampling interval value h is set.

8. the drilling well interval selecting arrangement of a kind of sand body structure as claimed in claim 5, it is characterized in that, described shale content computing module comprises that natural gamma (GR) changes relative value computing module, sampled point shale content computing module, shale content mean value calculation module, wherein:

Described GR changes relative value computing module, changes relative value SH for calculating each sampled point natural gamma in described processing interval;

Described sampled point shale content computing module, for calculating the shale content V of each sampled point in described processing interval _sh, its design formulas is:

$V_{\mathrm{sh}}=\frac{2^{\mathrm{GCUR}\&times;\mathrm{SH}}-1}{2^{\mathrm{GCUR}}-1}\&times;100\%$

In above formula, GCUR is Xi Erqi index;

Described shale content mean value calculation module, for calculating all sampled point shale content V in described processing interval _shaverage

9. a well logging characterizing method for sand body structure, is characterized in that, comprises following treatment step:

S110: the Natural Gamma-ray Logging Curves sampling number of choosing institute's layer to be addressed according to and calculate the smooth degree GS of its Natural Gamma-ray Logging Curves;

S120: the average that calculates shale content in described processing interval

S130: the well logging characterization parameter Pss that sets up sand body structure according to the average of shale content and the smooth degree of its corresponding Natural Gamma-ray Logging Curves in described processing interval; The expression formula of setting up the well logging characterization parameter Pss of sand body structure described in it is:

$\mathrm{Pss}=\mathrm{GS}\&times;\stackrel{\&OverBar;}{V_{\mathrm{sh}}}$

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