Seismic wavelet-free estimation well seismic calibration method

Abstract

The invention belongs to the field of exploration geophysics, and particularly relates to a seismic wavelet-free estimation well seismic calibration method. Data collection: collecting seismic data processing results including a pre-stack depth migration superposition imaging result and an anisotropic parameter body result, and well logging data including well layering information and a seismic horizon velocity in a zero deviation well; speed fusion processing is carried out on the vertical speed V1N in the prestack depth migration anisotropy parameter body result and the seismic horizon speed V2p in the zero-deviation well of the drilling well in the logging information to obtain a well-seismic speed fusion body V3N; time shift delta t is determined according to the prestack depth migration superposition imaging result, the vertical velocity V1p and the well-seismic velocity fusion body V3p; and enabling the pre-stack depth to shift the time shift delta t of the stack imaging result, and determining the seismic interpretation of the deep marker bed. The seismic interpretation of the geologic horizon determined by the method is accurate, and the method has important significance in determining the position of the geologic model where the drilling well is located in the drilling process and predicting the target depth of the drilling well.

Description

Technical Field

[0001] The invention belongs to the field of exploration geophysics, and in particular relates to a well seismic calibration method for non-seismic wavelet estimation. Background Art

[0002] During the correction of the geological model while drilling, it is necessary to match the well position with the marker layer. The above-mentioned marker layer refers to a geological interface that is easy to identify and has a clear position in both seismic data and logging data. The key to well-seismic matching lies in well-seismic calibration, and the main purpose of well-seismic calibration is to obtain a seismic interpretation of the geological layer. At present, well-seismic calibration is usually based on the convolution theory model, and seismic wavelet estimation is required during the calibration process. In general, seismic wavelets are often difficult to estimate accurately, and different estimated seismic wavelets make it difficult to determine the well-seismic calibration results, that is, the seismic interpretation of the geological layer is difficult to determine. Different seismic wavelet estimates sometimes even bring tens of meters of errors to the seismic interpretation of the geological layer, which is very unfavorable for determining the geological model position of the current drilling and predicting the drilling target depth during the drilling process.

[0003] In view of this, the present invention is proposed. Summary of the invention

[0004] In order to solve the technical problems existing in the prior art, the present invention provides a well seismic calibration method without seismic wavelet estimation. The seismic interpretation of the geological layer determined by the method of the present invention is accurate, which is of great significance for determining the geological model position of the drilling during the drilling process and predicting the drilling target depth.

[0005] The present invention includes the following technical solutions:

[0006] The present invention provides a method for calibrating well seismic without seismic wavelet estimation, and the calibration method comprises the following steps:

[0007] Data collection, the data includes seismic data processing results and well logging data; the seismic data processing results include prestack depth migration stack imaging results and prestack depth migration anisotropic parameter volume results; the well logging data includes well stratification information and zero-bias well seismic layer velocity;

[0008] The vertical velocity V1 in the anisotropic parameter volume result of prestack depth migration is N and the zero-bias wellbore seismic velocity V2 in the well logging data p Velocity fusion processing is performed to obtain the well-seismic velocity fusion body V3 N ;

[0009] According to the pre-stack depth migration stacking imaging results, vertical velocity V1 p And well shock velocity fusion V3 p Determine the time shift Δt;

[0010] Time-shift the pre-stack depth migration stack imaging results by Δt and determine the seismic interpretation of the deep marker layer;

[0011] Where: V1 N ∈(V11, V12,,,,,V1 p ,,,,,V1 n ), V3 N ∈(V31, V32,,,,,V3 p ,,,,,V3 n ), n represents a positive integer, and p represents positive drilling.

[0012] Furthermore, the vertical velocity V1 in the seismic data processing results is N and the zero-bias wellbore seismic velocity V2 in the well logging data p Velocity fusion processing is performed to obtain the well-seismic velocity fusion body V3 N The steps include:

[0013] Take the vertical velocity V1 at the drilling position p and zero-bias well seismic velocity V2 P Calculate the proportional factor function Scal p ;

[0014] The scale factor function Scal p Interpolate and extrapolate to obtain the scale factor Scal N ;

[0015] Through the vertical speed V1 N and the scaling factor Scal N Calculate and obtain the well-seismic velocity fusion body V3 N ;

[0016] Among them: Scal N ∈(Scal1,Scal2,,,,,Scal p ,,,,Scal n ).

[0017] Furthermore, the well seismic velocity fusion body V3 N Calculated by the following formula:

[0018] V3 N =V1 N *Scal N .

[0019] Furthermore, according to the pre-stack depth migration stacking imaging results, vertical velocity V1 p And well shock velocity fusion V3 p Determining the time shift Δt comprises the following steps:

[0020] Read the seismic interpretation depth value D1 of the shallow marker geological layer from the pre-stack depth migration stack imaging results p , and at the same time obtain the shallow marker layer well layer depth value D3 p ;

[0021] Get vertical speed V1 p The corresponding time and depth relationship curve DT1 p , Well Seismic Velocity Fusion V3 p The corresponding time and depth relationship curve DT3 p ;

[0022] By depth value D1 p The relationship curve between time and depth DT1 p Time T1 p and depth value D3 p The relationship between time and depth DT3 p Time T3 p Determine the time shift Δt.

[0023] Furthermore, the time shift Δt is obtained by the following formula:

[0024] Δt=T3 p -T1 p .

[0025] Furthermore, the seismic interpretation of pre-stack depth migration stacking imaging results by time shifting Δt and determining deep marker layers includes the following steps:

[0026] The pre-stack depth migration stacking imaging results are converted from the vertical velocity V1 N scale to time domain;

[0027] Shift the pre-stack depth migration stack imaging results in the time domain by Δt;

[0028] The pre-stack depth migration stacking imaging results in the time domain after time shift are combined into the well-seismic velocity fusion volume V3 N Scaling to the depth domain gives the seismic interpretation of the deep marker layer.

[0029] Furthermore, the data collected includes seismic data processing results and logging data within the range of Akm*Akm centered on the drilling plane position;

[0030] Wherein: A is a positive real number.

[0031] Furthermore, A=6.

[0032] By adopting the above technical solution, the present invention has the following advantages:

[0033] 1. The present invention is similar to the well-seismic calibration based on the convolution theory model in that both use the velocity function to integrate the time domain data to obtain the calibration result in the depth domain; the difference is that the present invention does not require seismic wavelet estimation, while the well-seismic calibration based on the convolution theory model requires seismic wavelet estimation, which is easy to introduce human errors.

[0034] 2. In the present invention, the well seismic velocity is integrated, the time shift Δt and the ratio, time shift, and re-ratio are determined. The newly obtained re-ratio data body is as long as the deep well stratification is in the zero-bias well seismic layer velocity V2 P Within this range, the seismic interpretation of the accurate geological position of the deep marker layer can be obtained. The results can be further used to determine the geological model position of the current drilling process and predict the drilling target depth. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 This is a flow chart of a method for estimating well seismic calibration without seismic wavelet in an embodiment of the present invention;

[0037] Figure 2 A geological model diagram while drilling in an embodiment of the present invention;

[0038] Figure 3 It is a plan view of the data collection range in the embodiment of the present invention;

[0039] Figure 4 This is a schematic diagram of well seismic velocity fusion in an embodiment of the present invention;

[0040] Figure 5 It is a speed fusion diagram in an embodiment of the present invention;

[0041] Figure 6 Determine a time shift Δt diagram in an embodiment of the present invention;

[0042] Figure 7 It is a scale, time shift and re-scale diagram of the pre-stack depth migration stack imaging results in an embodiment of the present invention;

[0043] Figure 8 for Figure 7 A partial map of

[0044] Fig. 9 for Figure 7 A partial map of

[0045] Fig.10 This is a seismic interpretation map for determining a deep marker layer in an embodiment of the present invention. DETAILED DESCRIPTION

[0046] The following description provides many different embodiments or examples for implementing different features of the present invention. The components and arrangements described in the following specific examples are only used to simplify the present invention and are only used as examples, not to limit the present invention.

[0047] like Figure 1 As shown, this embodiment provides a method for calibrating well seismic without seismic wavelet estimation, and the calibration method comprises the following steps:

[0048] Data collection, the data includes seismic data processing results and well logging data; the seismic data processing results include prestack depth migration stack imaging results and prestack depth migration anisotropic parameter volume results; the well logging data includes well stratification information and zero-bias well seismic layer velocity;

[0049] The vertical velocity V1 in the anisotropic parameter volume result of prestack depth migration is N and the zero-bias wellbore seismic velocity V2 in the well logging data p Velocity fusion processing is performed to obtain the well-seismic velocity fusion body V3 N ;

[0050] According to the pre-stack depth migration stacking imaging results, vertical velocity V1 p And well shock velocity fusion V3 p Determine the time shift Δt;

[0051] Time-shift the pre-stack depth migration stack imaging results by Δt and determine the seismic interpretation of the deep marker layer;

[0052] Where: V1 N ∈(V11, V12,,,,,V1 p ,,,,,V1 n ), V3 N ∈(V31, V32,,,,,V3 p ,,,,,V3 n ), n represents a positive integer, and p represents positive drilling.

[0053] Furthermore, the vertical velocity V1 in the seismic data processing results is N and the zero-bias wellbore seismic velocity V2 in the well logging data P Velocity fusion processing is performed to obtain the well-seismic velocity fusion body V3 N The steps include:

[0054] Take the vertical velocity V1 at the drilling position pand zero-bias well seismic velocity V2 P Calculate the proportional factor function Scal p ;

[0055] The scale factor function Scal p Interpolate and extrapolate to obtain the scale factor Scal N ;

[0056] Through the vertical speed V1 N and the scaling factor Scal N Calculate and obtain the well-seismic velocity fusion body V3 N ;

[0057] Among them: Scal N ∈(Scal1,Scal2,,,,,Scal p ,,,,Scal n ).

[0058] Furthermore, the well seismic velocity fusion body V3 N Calculated by the following formula:

[0059] V3 N =V1 N *Scal N .

[0060] Furthermore, according to the pre-stack depth migration stacking imaging results, vertical velocity V1 p And well shock velocity fusion V3 p Determining the time shift Δt comprises the following steps:

[0061] Read the seismic interpretation depth value D1 of the shallow marker geological layer from the pre-stack depth migration stack imaging results p , and at the same time obtain the shallow marker layer well layer depth value D3 p ;

[0062] Get vertical speed V1 p The corresponding time and depth relationship curve DT1 p , Well Seismic Velocity Fusion V3 p The corresponding time and depth relationship curve DT3 p ;

[0063] By depth value D1 p The relationship curve between time and depth DT1 p Time T1 p and depth value D3 p The relationship between time and depth DT3 p Time T3 p Determine the time shift Δt.

[0064] Furthermore, the time shift Δt is obtained by the following formula:

[0065] Δt=T3 p -T1 p .

[0066] Furthermore, the seismic interpretation of the deep marker layer determined by the time shift Δt of the pre-stack depth migration stack imaging results includes the following steps:

[0067] The pre-stack depth migration stacking imaging results are converted from the vertical velocity V1 N scale to time domain;

[0068] Shift the pre-stack depth migration stack imaging results in the time domain by Δt;

[0069] The pre-stack depth migration stacking imaging results in the time domain after time shift are combined into the well-seismic velocity fusion volume V3 N Scaling to the depth domain gives the seismic interpretation of the deep marker layer.

[0070] Furthermore, the data collected includes seismic data processing results and logging data within the range of Akm*Akm centered on the drilling plane position;

[0071] Wherein: A is a positive real number.

[0072] Furthermore, A=6.

[0073] The method based on this embodiment is explained by taking the seismic wavelet estimation of the bottom boundary of the Ordovician Sangtamu Formation as an example. The logging data and well logging interpretation show that the bottom of the well being drilled is about 20 meters deep at the bottom boundary (Os) of the Ordovician Sangtamu Formation. Figure 2 It is a geological model map while drilling. The drilling target is the dissolved holes deeper than 6000 meters in the profile of pre-stack depth migration and superposition imaging results. It is known that the shallow marker layer on the well does not match the seismic imaging position, and there is a deviation in the geological model position of the current drilling well, and the seismic interpretation of the bottom boundary (Os) of the deep marker layer, the Ordovician Sangtamu Formation, is unclear.

[0074] Data collection. Including the seismic data processing results within the range of 6km*6km along / vertical to the main survey line of seismic data with the positive drilling plane as the center (including the pre-stack depth migration stack imaging results, the vertical velocity V1 in the pre-stack depth migration anisotropic parameter body results) N ) and logging data (including well layer information of the well being drilled, zero-bias well mid-well seismic layer velocity V2 p etc.), such as Figure 3 As shown, this specific embodiment has collected all the required data, the collected stratification information and depth information of the well are accurate, and the collected zero-bias well seismic layer velocity of the well includes the entire range from the shallow layer to the current bottom of the well.

[0075] Velocity fusion. Take the vertical velocity V1 at the drilling position p and zero-bias well seismic velocity V2 P Calculate the proportional factor function Scal p ; Set the scale factor function Scal p Interpolate and extrapolate to obtain the scale factor Scal N ; through V3 N =V1 N *Scal N Calculate and obtain the well-seismic velocity fusion body V3 N , V3 N ∈(V31, V32,,,,,V3 p ,,,,,V3 n ).

[0076] like Figure 4 As shown, the vertical well seismic velocity fusion body V3 at the drilling position p The seismic interval velocity V2 in the zero-bias well during the drilling section p , other sections are vertical speed V1 p ; In the horizontal space, accurate well seismic velocity fusion is performed on the drilling position, and simple interpolation and extrapolation under the constraint of the layer are performed on other positions. The well seismic velocity fusion of this specific embodiment is as follows Figure 5 shown.

[0077] Determine the time shift Δt. First, the seismic interpretation of the Carboniferous bottom boundary (C) of the shallow marker layer is known to be a strong trough, and the seismic interpretation depth value D1 of the shallow marker geological layer is read from the prestack depth migration stack imaging results. p is 4271m, such as Figure 6 As shown, the shallow marker layer well stratification depth value D3 is obtained at the same time p is 4272m. Secondly, extract the vertical velocity V1 at the drilling position p And well shock velocity fusion V3 p And get the relationship curve DT1 between time and depth respectively p , time and depth relationship curve DT3 p ,like Figure 6 Next, the depth relationship curve DT1 p Read D1 p The corresponding time T1 p The relationship between time and depth is 3541.2ms. p Read D3 p Corresponding time T3 p is 3539.8ms. Finally, calculate the shallow marker layer time shift Δt=T3 p -T1 p =-1.4ms.

[0078] Prestack depth migration stack imaging results scale, time shift, and re-scale, such as Figure 7 The time shift here is obtained at the drilling position and uniformly applied to all data volumes. Figure 8 As shown in the figure, the prestack depth migration stack imaging results are converted into the vertical velocity V1 in the prestack depth migration anisotropic parameter volume results. N The time domain data volume is obtained by scaling to the time domain, and then the time domain data volume is shifted by Δt, such as Fig. 9 As shown in the figure, the time-shifted time domain data volume is finally fused into the well seismic velocity volume V3 N Scale to the depth domain to obtain a rescaled data volume.

[0079] Determine the seismic interpretation of the deep marker layer. Then the proportional data volume is matched with the well seismic at the bottom of the Carboniferous in the shallow marker layer (C), that is, the seismic data processing results of the shallow marker layer have been matched with the well layer depth, and the deep well layer is in the zero-bias well seismic layer velocity V2 p If the seismic interpretation of the deep marker layer is within the range, the seismic interpretation of the deep marker layer can be accurately determined, that is, the waveform position of the seismic phase axis in the re-proportional data volume corresponding to the deep well layer is the seismic interpretation of the geological position of the deep marker layer. The seismic interpretation of the bottom boundary of the Ordovician Sangtamu Formation (Os) of the deep marker layer is the valley peak zero phase, such as Fig.10 shown.

[0080] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0081] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for estimating well seismic calibration without earthquake wavelet, characterized in that: The calibration method comprises the following steps: Data collection, the data includes seismic data processing results and well logging data; the seismic data processing results include prestack depth migration stack imaging results and prestack depth migration anisotropic parameter volume results; the well logging data includes well stratification information and zero-bias well seismic layer velocity; The vertical velocity V1 in the prestack depth migration anisotropic parameter volume result is N and the zero-bias wellbore seismic velocity V2 in the well logging data p Velocity fusion processing is performed to obtain the well-seismic velocity fusion body V3 N ; According to the pre-stack depth migration stacking imaging results, vertical velocity V1 p And well shock velocity fusion V3 p Determine the time shift Δt; Time-shift the pre-stack depth migration stack imaging results by Δt and determine the seismic interpretation of the deep marker layer; Where: V1 N ∈(V11, V12,,,,,V1 p ,,,,,V1 n ), V3 N ∈(V31, V32,,,,,V3 p ,,,,,V3 n ), n represents a positive integer, and p represents positive drilling.

2. A method for estimating well seismic calibration without earthquake wavelet as claimed in claim 1, characterized in that: The vertical velocity V1 in the seismic data processing results N and the zero-bias wellbore seismic velocity V2 in the well logging data p Velocity fusion processing is performed to obtain the well-seismic velocity fusion body V3 N The steps include: Take the vertical velocity V1 at the drilling position p and zero-bias well seismic velocity V2 P Calculate the proportional factor function Scal p ; The scale factor function Scal p Interpolate and extrapolate to obtain the scale factor Scal N ; Through the vertical speed V1 N and the scaling factor Scal N Calculate and obtain the well-seismic velocity fusion body V3 N ; Among them: Scal N ∈(Scal1,Scal2,,,,,Scal p ,,,,Scal n ).

3. A method for estimating well seismic calibration without earthquake wavelet as claimed in claim 2, characterized in that: The well seismic velocity fusion body V3 N Calculated by the following formula: V3 N =V1 N *Scal N 。 4. A method for estimating well seismic calibration without earthquake wavelet as claimed in claim 1, characterized in that: According to the pre-stack depth migration stacking imaging results, vertical velocity V1 p And well shock velocity fusion V3 p Determining the time shift Δt comprises the following steps: Read the seismic interpretation depth value D1 of the shallow marker geological layer from the pre-stack depth migration stack imaging results p , and at the same time obtain the shallow marker layer well layer depth value D3 p ; Get vertical speed V1 p The corresponding time and depth relationship curve DT1 p , Well Seismic Velocity Fusion V3 p The corresponding time and depth relationship curve DT3 p ; By depth value D1 p The relationship between time and depth DT1 p Time T1 p and depth value D3 p The relationship between time and depth DT3 p Time T3 p Determine the time shift Δt.

5. A method for estimating well seismic calibration without earthquake wavelet as claimed in claim 4, characterized in that: The time shift Δt is obtained by the following formula: Δt=T3 p -T1 p 。 6. A method for estimating well seismic calibration without earthquake wavelet as claimed in claim 1, characterized in that: The seismic interpretation of pre-stack depth migration stack imaging results by time shifting Δt and determining deep marker layers includes the following steps: The pre-stack depth migration stacking imaging results are converted from the vertical velocity V1 N scale to time domain; Shift the pre-stack depth migration stack imaging results in the time domain by Δt; The pre-stack depth migration stacking imaging results in the time domain after time shift are combined into the well-seismic velocity fusion volume V3 N Scaling to the depth domain gives the seismic interpretation of the deep marker layer.

7. A method for estimating well seismic calibration without earthquake wavelet as claimed in claim 1, characterized in that: The data collection includes seismic data processing results and well logging data within the range of Akm*Akm centered at the drilling plane position; Wherein: A is a positive real number.

8. A method for estimating well seismic calibration without earthquake wavelet as claimed in claim 1, characterized in that: Said A=6.

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