Method and system for recovering distorted sound wave and density logging curve

Abstract

The invention relates to a method and system for recovering a distorted sound wave and density logging curve, and the method comprises the steps: firstly obtaining a mudstone skeleton value of a logging mudstone section, and extracting a natural potential curve, a natural gamma curve, a neutron curve and a density curve of rock lithology at all logging depths; according to the minimum voltage value and the maximum voltage value of the natural potential curve and the voltage value of any depth in the well logging, or the minimum radioactive intensity value and the maximum radioactive intensity value of the natural gamma curve and the radioactive intensity value of any depth in the well logging, the shale content of the depth is calculated; then calculating a neutron porosity value according to the shale content and a neutron logging value of the neutron curve, calculating a density porosity value according to a mudstone density skeleton value and a density logging value of the density curve, and further calculating a total porosity value; finally, according to the shale content, the total porosity value, the mudstone sound wave time difference skeleton value or the mudstone density skeleton value, a real sound wave logging curve and a real density logging curve of the mudstone expanding section are calculated.

Description

Technical Field

[0001] The present invention relates to the technical field of geological engineering, and particularly relates to a method and system for restoring distorted acoustic wave and density logging curves. Background Art

[0002] In the process of oil and gas exploration and development, logging has always been one of the important means of oil and gas exploration and development. Especially in aspects such as seismic synthetic record calibration, high-quality reservoir prediction, and oil and gas detection, the accuracy of logging curves can directly affect the reliability evaluation of data. During the drilling process, the shale section is prone to collapse to form an irregular borehole, resulting in distortion of density and acoustic wave logging values, which will seriously affect the accuracy of acoustic wave logging curves and density logging curves and subsequent seismic horizon calibration.

[0003] Currently, common logging curve correction methods include multi-curve fitting method, empirical formula method, etc. However, it is difficult to build models in the shale hole enlargement section (i.e., the area where collapse occurs in the shale section, that is, the section where the borehole size is larger than the bit diameter in actual drilling), and it is only suitable for a certain formation, and the effect is poor in other formations. To address these problems, it is urgent to study a method for restoring distorted acoustic wave and density logging curves to meet the correction of acoustic wave and density values in the shale hole enlargement section of different formations. Summary of the Invention

[0004] To solve the problems existing in the process of correcting the accuracy of logging curves, such as difficult modeling, only suitable for a certain formation, and low accuracy of logging curves, the present invention provides a method for restoring distorted acoustic wave and density logging curves. Based on the shale matrix values in the logging shale section, spontaneous potential curves, natural gamma curves, neutron curves, and density curves of rocks at all logging depths, and using specific calculation methods and formulas, the true acoustic wave logging curve and density logging curve in the shale hole enlargement section are calculated, effectively improving the accuracy and calculation efficiency. The present invention also relates to a system for restoring distorted acoustic wave and density logging curves.

[0005] The technical solution of the present invention is as follows:

[0006] A method for restoring distorted acoustic wave and density logging curves, characterized by comprising the following steps:

[0007] Parameter and curve acquisition step: Obtain the shale matrix values in the logging shale section by means of a histogram, and extract the spontaneous potential curve, natural gamma curve, neutron curve, and density curve of the rock lithology at all logging depths, where the shale matrix values include shale acoustic travel time matrix values and shale density matrix values;

[0008] Steps for calculating shale content: Calculate the shale content at a certain depth according to the minimum voltage value, maximum voltage value of the spontaneous potential curve, and the voltage value at any depth during logging, or according to the minimum radioactivity intensity value, maximum radioactivity intensity value of the natural gamma curve, and the radioactivity intensity value at any depth during logging;

[0009] Steps for calculating porosity values: Calculate the neutron porosity value according to the shale content and the neutron logging value of the neutron curve, calculate the density porosity value according to the shale density matrix value and the density logging value of the density curve, and calculate the total porosity value at any depth during logging according to the neutron porosity value and the density porosity value;

[0010] Steps for calculating logging curves: Calculate the acoustic logging curve of the enlarged hole section in the shale section according to the shale content, total porosity value, and shale acoustic time matrix value, and calculate the density logging curve of the enlarged hole section in the shale section according to the shale content, total porosity value, and shale density matrix value.

[0011] Preferably, in the step of obtaining parameters and curves, obtaining the shale matrix values of the logging shale section by means of a histogram includes: respectively statistically the relationship between the frequency and the acoustic time and the relationship between the frequency and the density of the regular wellbore section by means of a histogram, and taking the acoustic time value and the density value corresponding to the frequency peak as the shale acoustic time matrix value and the shale density matrix value respectively.

[0012] Preferably, in the step of obtaining parameters and curves, the lithology includes color, composition, structure, cement, and cementation type.

[0013] Preferably, the composition includes shale, sandstone, limestone, dolomitic limestone, dolomitic marl, dolomite, and shale laminae, and the structure includes the grain size, sorting, and rounding of mineral particles.

[0014] Preferably, in the step of obtaining parameters and curves, preprocessing is also performed on the extracted spontaneous potential curve, natural gamma curve, neutron curve, and density curve, and the preprocessing includes curve depth correction.

[0015] A system for restoring distorted acoustic and density logging curves, characterized in that it includes a parameter and curve acquisition module, a shale content calculation module, a porosity value calculation module, and a logging curve calculation module connected in sequence,

[0016] The parameter and curve acquisition module obtains the shale matrix values of the logging shale section by means of a histogram, and extracts the spontaneous potential curve, natural gamma curve, neutron curve, and density curve of the rock lithology at all depths of logging. The shale matrix values include the shale acoustic time matrix value and the shale density matrix value;

[0017] The shale content calculation module calculates the shale content at a certain depth according to the minimum voltage value, the maximum voltage value of the spontaneous potential curve, and the voltage value at any depth in the logging, or according to the minimum radioactivity intensity value, the maximum radioactivity intensity value of the natural gamma curve, and the radioactivity intensity value at any depth in the logging;

[0018] The porosity value calculation module calculates the neutron porosity value according to the shale content and the neutron logging value of the neutron curve, calculates the density porosity value according to the shale density matrix value and the density logging value of the density curve, and calculates the total porosity value at any depth in the logging according to the neutron porosity value and the density porosity value;

[0019] The logging curve calculation module calculates the acoustic logging curve of the enlarged diameter section in the shale section according to the shale content, the total porosity value, and the shale acoustic time matrix value, and calculates the density logging curve of the enlarged diameter section in the shale section according to the shale content, the total porosity value, and the shale density matrix value.

[0020] Preferably, in the parameter and curve acquisition module, obtaining the shale matrix values of the logging shale section by means of a histogram includes: respectively statistically analyzing the relationship between the frequency and the acoustic time and the relationship between the frequency and the density of the wellbore regular section by means of a histogram, and taking the acoustic time value and the density value corresponding to the frequency peak as the shale acoustic time matrix value and the shale density matrix value respectively.

[0021] Preferably, the lithology includes color, composition, structure, cement, and cementation type.

[0022] Preferably, the composition includes shale, sandstone, limestone, dolomitic limestone, dolomitic marble, dolomite, and shale laminae, and the structure includes the grain size, sorting, and rounding of mineral particles.

[0023] Preferably, in the parameter and curve acquisition module, preprocessing is also performed on the extracted spontaneous potential curve, natural gamma curve, neutron curve, and density curve, and the preprocessing includes curve depth correction.

[0024] The beneficial effects of the present invention are:

[0025] The present invention relates to a method for restoring distorted acoustic wave and density logging curves. First, the shale matrix values of the logging shale section are obtained by the histogram method, and the spontaneous potential curve, natural gamma curve, neutron curve, and density curve of the rock lithology at all depths of the logging are extracted. The shale matrix values include the shale acoustic time difference matrix value and the shale density matrix value. Then, according to the minimum voltage value, maximum voltage value of the spontaneous potential curve, and the voltage value at any depth in the logging, or according to the minimum radioactivity intensity value, maximum radioactivity intensity value of the natural gamma curve, and the radioactivity intensity value at any depth in the logging, the shale content at this depth is calculated. Then, according to the shale content and the neutron logging value of the neutron curve, the neutron porosity value is calculated. According to the shale density matrix value and the density logging value of the density curve, the density porosity value is calculated. According to the neutron porosity value and the density porosity value, the total porosity value at any depth in the logging is calculated. Finally, according to the shale content, the total porosity value, and the shale acoustic time difference matrix value, the acoustic logging curve of the enlarged diameter section in the shale section is calculated, and according to the shale content, the total porosity value, and the shale density matrix value, the density logging curve of the enlarged diameter section in the shale section is calculated. The calculated acoustic logging curve and density logging curve have high accuracy, realizing the restoration of the true acoustic logging curve and density logging curve of the shale enlarged diameter section. The present invention uses curves such as the spontaneous potential curve and natural gamma curve, which are less affected by borehole enlargement, to restore the true lithology profile of the shale section. Based on the shale matrix values, the true acoustic wave and density logging values of the true formation of the enlarged diameter section are calculated inversely, realizing the correction of the distorted acoustic wave and density logging curves of the shale enlarged diameter section. The high-quality acoustic wave and density curves can improve the accuracy of time-depth conversion of seismic data and the imaging accuracy in the later stage. The calculation process of the present invention is simple, fast, and efficient, and can meet the correction of acoustic wave and density values in the shale enlarged diameter section of different formations. The method flow proposed by the present invention can be widely applied to the performance research of the shale enlarged diameter section.

[0026] The present invention also relates to a system for restoring distorted acoustic wave and density logging curves. This system corresponds to the above method for restoring distorted acoustic wave and density logging curves and can be understood as a system for implementing the above method for restoring distorted acoustic wave and density logging curves. The system includes a parameter and curve acquisition module, a shale content calculation module, a porosity value calculation module, and a logging curve calculation module connected in sequence. Each module works in coordination with each other. The shale matrix values of the logging shale section are obtained by the histogram method, and the spontaneous potential curve, natural gamma curve, neutron curve, and density curve of the rock at all depths of the logging are extracted, and the true acoustic logging curve and density logging curve of the shale enlarged diameter section are calculated using specific calculation methods and formulas, effectively improving the accuracy. The calculation process is simple, fast, and efficient, and can meet the correction of acoustic wave and density values in the shale enlarged diameter section of different formations. Description of the Drawings

[0027] Figure 1This is the flow chart of the method for restoring distorted acoustic wave and density logging curves of the present invention.

[0028] Figure 2 This is the histogram of the frequency and acoustic wave time difference of the regular section of shale in the present invention.

[0029] Figure 3 This is the histogram of the frequency and density of the regular section of shale in the present invention.

[0030] Figure 4 This is the schematic diagram before and after correction of the acoustic wave logging curve and density logging curve of the enlarged diameter section of shale in the present invention. Detailed implementation manners

[0031] For a clearer understanding of the content of the present invention, it will be described in detail in conjunction with the accompanying drawings and embodiments.

[0032] The present invention relates to a method for restoring distorted acoustic wave and density logging curves. The flow chart of this method is as Figure 1 shown, and successively includes the following steps:

[0033] I. Parameter and curve acquisition step: Obtain the shale matrix values of the logging shale section through the histogram method, and extract the spontaneous potential curve, natural gamma curve, neutron curve and density curve of the lithology of the rock at all depths of the logging. The shale matrix values include the shale acoustic wave time difference matrix value and the shale density matrix value.

[0034] Specifically, as Figure 2 and Figure 3 shown, first, use the histogram method to respectively count the relationship between the frequency and acoustic wave time difference and the relationship between the frequency and density of the regular section of the wellbore (the section where the difference between the wellbore size and the bit size is less than 0.5 in). The acoustic wave time difference value and density value corresponding to the frequency peak are respectively used as the shale acoustic wave time difference matrix value and the shale density matrix value. Figure 2 The histogram of the frequency and acoustic wave time difference of the regular section of shale shown in Figure 3 can also be called the statistical distribution diagram of the time difference value of the shale in the regular section of the well diameter;

[0035] II. Steps for calculating shale content: Calculate the shale content at a certain depth based on the minimum voltage value, maximum voltage value of the spontaneous potential curve, and the voltage value at any depth during logging, or based on the minimum radioactivity intensity value, maximum radioactivity intensity value of the natural gamma curve, and the radioactivity intensity value at any depth during logging. The shale content is calculated according to the following formula:

[0036] SHI=(LOG - LOG min ) / (LOG max - LOG min ) (1)

[0037] VSH=(2 GCUR·SHI - 1) / (2 GCUR - 1) (2)

[0038] In the above formula, GCUR is an empirical constant, taking 3.7 for strata in the Tertiary (a geological time term) and later, and 2 for strata before the Tertiary; LOG is the voltage value of the spontaneous potential curve or the radioactivity intensity value of the natural gamma curve at any depth during logging; LOG min is the minimum voltage value of the spontaneous potential curve or the minimum radioactivity intensity value of the natural gamma curve, LOG max is the maximum voltage value of the spontaneous potential curve or the maximum radioactivity intensity value of the natural gamma curve, and SHI is the shale index.

[0039] Among them, the minimum voltage value or minimum radioactivity intensity value can be considered as the voltage value of the spontaneous potential curve under pure sandstone (i.e., 100% sandstone content) or the radioactivity intensity value of the natural gamma curve under pure sandstone; the maximum voltage value or maximum radioactivity intensity value can be considered as the voltage value of the spontaneous potential curve under pure shale (i.e., 100% shale content) or the radioactivity intensity value of the natural gamma curve under pure sandstone.

[0040] III. Steps for calculating porosity value: Calculate the neutron porosity value based on the shale content and the neutron logging value of the neutron curve, calculate the density porosity value based on the shale density matrix value and the density logging value of the density curve, and calculate the total porosity value at any depth during logging based on the neutron porosity value and the density porosity value.

[0041] Specifically, first calculate the neutron porosity value based on the shale content and the neutron logging value of the neutron curve. The neutron porosity value POR N is calculated according to the following formula:

[0042] POR N =CNL - VSH * NSH (3)

[0043] In the above formula, CNL is the neutron log value (the neutron log value at any depth of the formation collected by the neutron logging tool); VSH is the shale content; NSH is the neutron matrix value of shale (i.e., the neutron log value when the shale content is 100%), which is generally used as a constant and takes 25%.

[0044] Then, calculate the density porosity value according to the density matrix value of shale and the density log value of the density curve. The density porosity value is calculated according to the following formula:

[0045] POR D =(DEN_MA - DEN) / (DEN_MA - DEN_F)-

[0046] VSH*(DEN_MA - DEN_SH) / (DEN_MA - DEN_F)(4)

[0047] In the above formula, DEN is the density log value, with the unit of g / cm 3 , DEN_MA is the sandstone matrix value (i.e., the density value when the sandstone content is 100%), which is generally used as a constant and takes 2.65 g / cm 3 , DEN_F is the density value of the fluid in the formation, which is generally used as a constant in a region and takes 1.08 g / cm 3 , DEN_SH is the density matrix value of shale.

[0048] Finally, calculate the total porosity value at any depth in the well logging according to the neutron porosity value and the density porosity value. The total porosity value PORT is calculated according to the following formula:

[0049]

[0050] In the above formula, POR N is the neutron porosity value after shale correction, and POR D is the density porosity value after shale correction.

[0051] IV. Well logging curve calculation steps: Calculate the acoustic well logging curve of the enlarged diameter section in the shale section according to the shale content, the total porosity value, and the acoustic travel time matrix value of shale, and calculate the density well logging curve of the enlarged diameter section in the shale section according to the shale content, the total porosity value, and the density matrix value of shale.

[0052] Specifically, first calculate the acoustic well logging curve of the enlarged diameter section in the shale section according to the shale content, the total porosity value, and the acoustic travel time matrix value of shale. The acoustic well logging curve is calculated according to the following formula:

[0053] AC_C=VSH*TSH + PORT*TF+(1 - VSH - PORT)*TMA (6)

[0054] In the above formula, AC_C is the sonic logging curve after correction of the enlarged diameter section of mudstone, TSH is the sonic travel time skeleton value of mudstone, VSH is the shale content, PORT is the total porosity value, TF is the sonic travel time of fluid, generally taken as a constant value of 189 μs / ft, TMA is the sonic travel time skeleton value of sandstone (i.e., the sonic travel time value when the sandstone content is 100%), generally taken as a constant value of 55.5 μs / ft.

[0055] Then, based on the shale content, total porosity value and the density skeleton value of mudstone, the density logging curve of the enlarged diameter section in the mudstone section is calculated. The density logging curve is calculated according to the following formula:

[0056] DEN_C = VSH * DEN_SH + PORT * DEN_F + (1 - VSH - PORT) * DEN_MA (7)

[0057] In the above formula, DEN_C is the density logging curve after correction of the enlarged diameter section of mudstone, VSH is the shale content, DEN_SH is the density skeleton value of mudstone, PORT is the total porosity value, DEN_F is the density value of the fluid in the formation, generally taken as a constant value in a certain area, generally taken as 1.08 g / cm 3 , DEN_MA is the density skeleton value of sandstone, generally taken as a constant value of 2.65 g / cm 3 .

[0058] After calculating the sonic logging curve and density logging curve of the enlarged diameter section of mudstone (i.e., the area where collapse occurs in the mudstone section, that is, the well section where the wellbore size is larger than the bit diameter in actual drilling), the calculated sonic logging curve and density logging curve of the enlarged diameter section of mudstone are respectively compared with the original sonic logging curve and original density logging curve of the mudstone section before logging collapse obtained by the logging instrument. As shown in the schematic diagrams of the sonic logging curve and density logging curve of the enlarged diameter section of mudstone before and after correction in Figure 4 , which are used to compare the sonic curve and density curve before and after correction. Based on the comparison results, it is found that the accuracy of the sonic logging curve and density logging curve calculated by the present invention can reach 90% compared with the original sonic logging curve and original density logging curve. Among them, SP: spontaneous potential curve; CAL: caliper curve; GR: natural gamma curve; RILD: deep induction resistivity curve; RILM: medium pole hard resistivity curve; RFOC: eight-lateral curve; CNL: neutron curve; DEN: density curve; AC: sonic travel time curve; VSH: shale content curve; PORT: porosity curve; DEN_C: corrected density curve; AC_C: corrected sonic travel time curve.

[0059] The present invention also relates to a recovery system for distorted acoustic wave and density logging curves. This system corresponds to the above-mentioned method for recovering distorted acoustic wave and density logging curves and can be understood as a system for implementing the above-mentioned method for recovering distorted acoustic wave and density logging curves. The system includes a parameter and curve acquisition module, a shale content calculation module, a porosity value calculation module, and a logging curve calculation module that are connected in sequence. Specifically,

[0060] The parameter and curve acquisition module obtains the shale matrix values of the shale section of the logging through the method of histogram, and extracts the spontaneous potential curve, natural gamma curve, neutron curve, and density curve of the lithology of the rock at all depths of the logging. The shale matrix values include the shale acoustic time difference matrix value and the shale density matrix value;

[0061] The shale content calculation module calculates the shale content at a certain depth according to the minimum voltage value, maximum voltage value of the spontaneous potential curve, and the voltage value at any depth during logging, or according to the minimum radioactivity intensity value, maximum radioactivity intensity value of the natural gamma curve, and the radioactivity intensity value at any depth during logging;

[0062] The porosity value calculation module calculates the neutron porosity value according to the shale content and the neutron logging value of the neutron curve, calculates the density porosity value according to the shale density matrix value and the density logging value of the density curve, and calculates the total porosity value at any depth during logging according to the neutron porosity value and the density porosity value;

[0063] The logging curve calculation module calculates the acoustic logging curve of the enlarged diameter section in the shale section according to the shale content, total porosity value, and shale acoustic time difference matrix value, and calculates the density logging curve of the enlarged diameter section in the shale section according to the shale content, total porosity value, and shale density matrix value.

[0064] Preferably, in the parameter and curve acquisition module, obtaining the shale matrix values of the shale section of the logging through the method of histogram includes: respectively statistically analyzing the relationship between the frequency and the acoustic time difference and the relationship between the frequency and the density in the regular wellbore section through the method of histogram, and taking the acoustic time difference value and density value corresponding to the frequency peak as the shale acoustic time difference matrix value and the shale density matrix value respectively.

[0065] Preferably, the lithology includes color, composition, structure, cement, and cementation type.

[0066] Preferably, the composition includes shale, sandstone, limestone, dolomitic limestone, dolomitic marl, dolomite, and shale laminations, and the structure includes the grain size, sorting, and rounding of mineral particles.

[0067] Preferably, in the parameter and curve acquisition module, the extracted spontaneous potential curve, natural gamma curve, neutron curve, and density curve are also preprocessed, and the preprocessing includes curve depth correction.

[0068] The present invention provides an objective and scientific method and system for restoring distorted acoustic wave and density logging curves. Based on the shale matrix value in the logging shale section, the spontaneous potential curve, natural gamma curve, neutron curve and density curve of the rock at all logging depths, and using specific calculation methods and formulas, the true acoustic wave logging curve and density logging curve of the shale hole enlargement section are calculated, effectively improving the accuracy and calculation efficiency.

[0069] It should be noted that the above specific embodiments can enable those skilled in the art to understand the present invention more comprehensively, but do not limit the present invention in any way. Therefore, although this specification has described the present invention in detail with reference to the drawings and embodiments, those skilled in the art should understand that the present invention can still be modified or equivalently replaced. In short, all technical solutions and their improvements that do not depart from the spirit and scope of the present invention should be covered by the protection scope of the patent of the present invention.

Claims

1. A method for restoring distorted acoustic wave and density logging curves, characterized in that, It includes the following steps: Parameter and curve acquisition step: Obtain the shale matrix values of the logging shale section through the histogram method, and extract the spontaneous potential curve, natural gamma curve, neutron curve, and density curve of the rock lithology at all logging depths. The shale matrix values include the shale acoustic time difference matrix value and the shale density matrix value; Shale content calculation step: Calculate the shale content at a certain depth according to the minimum voltage value, maximum voltage value of the spontaneous potential curve, and the voltage value at any depth in the logging, or according to the minimum radioactivity intensity value, maximum radioactivity intensity value of the natural gamma curve, and the radioactivity intensity value at any depth in the logging; Porosity value calculation step: Calculate the neutron porosity value according to the shale content and the neutron logging value of the neutron curve, calculate the density porosity value according to the shale density matrix value and the density logging value of the density curve, and calculate the total porosity value at any depth in the logging according to the neutron porosity value and the density porosity value; Logging curve calculation step: Calculate the acoustic logging curve of the enlarged diameter section in the shale section according to the shale content, total porosity value, and shale acoustic time difference matrix value, and calculate the density logging curve of the enlarged diameter section in the shale section according to the shale content, total porosity value, and shale density matrix value.

2. The method for restoring distorted acoustic wave and density logging curves according to claim 1, characterized in that, In the parameter and curve acquisition step, obtaining the shale matrix values of the shale section through the histogram method includes: respectively statistically analyzing the relationship between the frequency and acoustic time difference and the relationship between the frequency and density of the regular wellbore section through the histogram method, and taking the acoustic time difference value and density value corresponding to the frequency peak as the shale acoustic time difference matrix value and the shale density matrix value respectively.

3. The method for restoring distorted acoustic wave and density logging curves according to claim 1, characterized in that, In the parameter and curve acquisition step, the lithology includes color, composition, structure, cement, and cementation type.

4. The method for restoring the distorted acoustic wave and density logging curves according to claim 3, characterized in that, The composition includes shale, sandstone, limestone, dolomitic limestone, dolomitic marl, dolomite, and shale laminations, and the structure includes the grain size, sorting, and rounding of mineral particles.

5. The method for restoring distorted acoustic wave and density logging curves according to claim 1, characterized in that, In the parameter and curve acquisition step, preprocessing is also performed on the extracted spontaneous potential curve, natural gamma curve, neutron curve, and density curve. The preprocessing includes curve depth correction.

6. A recovery system for distorted acoustic wave and density logging curves, characterized in that, It includes a parameter and curve acquisition module, a shale content calculation module, a porosity value calculation module, and a logging curve calculation module connected in sequence. The parameter and curve acquisition module obtains the shale matrix values of the logging shale section through the histogram method, and extracts the spontaneous potential curve, natural gamma curve, neutron curve, and density curve of the rock lithology at all logging depths. The shale matrix values include the shale acoustic time difference matrix value and the shale density matrix value; The shale content calculation module calculates the shale content at a certain depth according to the minimum voltage value, maximum voltage value of the spontaneous potential curve, and the voltage value at any depth in the logging, or according to the minimum radioactivity intensity value, maximum radioactivity intensity value of the natural gamma curve, and the radioactivity intensity value at any depth in the logging; The porosity value calculation module calculates the neutron porosity value according to the shale content and the neutron logging value of the neutron curve, calculates the density porosity value according to the shale density matrix value and the density logging value of the density curve, and calculates the total porosity value at any depth in the logging according to the neutron porosity value and the density porosity value; The logging curve calculation module calculates the acoustic logging curve of the enlarged hole section in the shale section according to the shale content, total porosity value, and shale acoustic time difference matrix value, and calculates the density logging curve of the enlarged hole section in the shale section according to the shale content, total porosity value, and shale density matrix value.

7. The recovery system for distorted acoustic wave and density logging curves according to claim 6, wherein In the parameter and curve acquisition module, the shale matrix values of the logging shale section are obtained by the method of histogram, including: respectively statistically analyzing the relationship between the frequency and acoustic time difference and the relationship between the frequency and density of the regular hole section by the method of histogram, and taking the acoustic time difference value and density value corresponding to the frequency peak as the shale acoustic time difference matrix value and shale density matrix value respectively.

8. The recovery system for distorted acoustic wave and density logging curves according to claim 6, wherein The lithology includes color, composition, structure, cement, and cementation type.

9. The restoration system for distorted acoustic wave and density logging curves according to claim 8, characterized in that, The composition includes shale, sandstone, limestone, dolomitic limestone, dolomitic limestone, dolomite, and shale laminations, and the structure includes the grain size, sorting, and rounding of mineral particles.

10. The restoration system for distorted acoustic wave and density logging curves according to claim 6, characterized in that, In the parameter and curve acquisition module, the natural potential curve, natural gamma curve, neutron curve, and density curve extracted are also preprocessed, and the preprocessing includes curve depth correction.

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