Device and method for acquiring optical fiber time-frequency electromagnetic and four-component seismic data in wellTechnical Field
The invention belongs to the technical field of wellbore geophysical exploration, and particularly relates to an array type ground-well (ground excitation-well receiving) three-component optical fiber time-frequency electromagnetic and four-component optical fiber seismic data acquisition technology.
Background
Geophysical prospecting methods mainly include prospecting methods such as an earthquake method, a direct current method, a magnetic method, a gravitational method and an electromagnetic method. The electromagnetic method is also called as electromagnetic induction method, and the method for prospecting by utilizing the electromagnetic induction principle is called as electromagnetic method according to the difference of conductivity and magnetic permeability of rock or ore.
The application of the ground time-frequency electromagnetic exploration technology plays an important role in the aspects of joint interpretation of a structural band and a special target, joint detection and evaluation of oil and gas trapping and the like. Well-to-earth (well stimulation-surface reception) electromagnetic exploration technology has been developed over the last two decades as a more sophisticated approach. The method of electromagnetic field excitation can be classified into frequency domain excitation and time domain excitation. A limitation of frequency domain (continuous wave) excitation is the strong coupling between the transmitter and the receiver, so that the source field signal from the transmitter directly to the receiver is far stronger than the signal from the formation, and it is difficult to accurately measure the electromagnetic field signal received from the formation. Although the combination of multi-target processing techniques and the application of multiple sets of measurement data provides information about the target formation of interest, the resulting net signal is still small compared to the total measurement signal and the useful information is minimal.
U.S. patent specification US6739165B1 discloses a well electromagnetic measurement system and method for determining reservoir fluid properties. The system firstly collects an initial natural magnetotelluric field through magnetotelluric data collection equipment arranged on the ground, measures the initial electromagnetic field of the reservoir through electromagnetic sensors arranged on the ground and underground, then calculates the resistivity or conductivity of the underground reservoir through inversion, and deduces an initial ground model and an initial contact surface of an initial underground fluid such as oil water or gas water according to the initial resistivity or the conductivity. And repeating the measurement of the electromagnetic field of the reservoir stratum in the ground and the well after a period of time, and inversely calculating the resistivity or the conductivity of the underground reservoir stratum, so as to deduce the ground model at the moment and the spatial distribution of the contact surfaces of the underground fluid and different fluids at the moment. The production of a hydrocarbon reservoir is monitored by monitoring the change in spatial distribution of fluid and different fluid contact surfaces in a subsurface reservoir. However, such well electromagnetic measurement systems are susceptible to interference from man-made noise on the surface, reducing the signal-to-noise ratio of the electromagnetic data.
Chinese patent ZL201520648262.9 discloses a device for acquiring time-frequency electromagnetic exploration data of a ground-well. The device comprises a ground high-power emission source and a well time-frequency electromagnetic signal receiving and collecting device, wherein the well time-frequency electromagnetic signal receiving and collecting device is connected with an instrument car on the ground through a logging cable, the instrument car controls the depth position of the well time-frequency electromagnetic signal receiving and collecting device in the well, the ground high-power pulse emission source comprises a high-power pulse emission control device and an emission antenna, and the well time-frequency electromagnetic signal receiving and collecting device comprises a data acquisition and transmission nipple, a pair of three-component magnetic field sensors and a vertical component electric field sensor. The device can only measure the vertical electric field component by using a pair of non-polarized electrode rings or non-polarized electrode blocks arranged outside the data acquisition pup joint. In addition, the underground data acquisition and transmission nipple and the three-component magnetic field sensor are limited by internal electronic devices and the temperature resistance of magnetic induction coils or fluxgate sensor materials, and can not work normally in a high-temperature well, so that the application range of the instrument device is affected.
Disclosure of Invention
In order to solve the problem that the conventional underground electromagnetic and seismic data acquisition instrument cannot work at the height Wen Jingli, the invention provides an array type underground three-component optical fiber time-frequency electromagnetic and four-component optical fiber seismic data acquisition device.
The invention also provides a multi-component geophysical data acquisition method based on the well array type optical fiber electromagnetic and optical fiber seismic signal receiving and acquiring device, which can acquire underground full wave field seismic signals and provide reference data for subsequent interpretation and evaluation of reservoir parameters, interpretation and evaluation of stratum oil gas or high-polarization mineral parameters and imaging of high-resolution geological structures around the well.
One of the technical schemes adopted by the invention is as follows: an array type well three-component optical fiber time-frequency electromagnetic and four-component optical fiber seismic data acquisition device, comprising: the underground artificial seismic source (4), the underground high-power electromagnetic pulse emission source (1) and the underground optical fiber electromagnetic and optical fiber seismic signal receiving and collecting device (6), wherein the underground optical fiber electromagnetic and optical fiber seismic signal receiving and collecting device (6) is connected with an instrument car (5) on the ground through an armored optical fiber cable (12), and the armored optical fiber cable (12) connected with the instrument car (5) controls the depth position of the underground optical fiber electromagnetic and optical fiber seismic signal receiving and collecting device (6) in the well;
The ground artificial seismic source (4) excites seismic waves to the ground, and the ground high-power electromagnetic pulse emission source comprises a high-power electromagnetic pulse emission control device (1) and an emission antenna (2), wherein the high-power electromagnetic pulse emission control device (1) provides high-power pulse excitation current (3) for the emission antenna (2);
the well array type optical fiber electromagnetic and optical fiber seismic signal receiving and collecting device (6) comprises a plurality of data collecting pup joints (11), a three-component optical fiber magnetic field sensor (7), a three-component optical fiber electric field sensor (8), a four-component optical fiber seismic signal sensing unit (9) and a three-component optical fiber attitude sensor (10) which are arranged in the data collecting pup joints (11); the data acquisition pups arranged in an array mode are connected through an armored optical fiber cable (12);
In the data acquisition nipple (11), a three-component optical fiber electric field sensor (8) is arranged at the upper end of the data acquisition nipple (11), a three-component optical fiber magnetic field sensor (7) is arranged at the lower end of the data acquisition nipple (11), a four-component optical fiber seismic signal sensing unit (9) is arranged in the middle of the data acquisition nipple (11), and a three-component optical fiber attitude sensor (10) is arranged next to the four-component optical fiber seismic signal sensing unit (9).
The distance between two adjacent three-component optical fiber magnetic field sensors (7) in the array is 10m, and the distance between two adjacent three-component optical fiber electric field sensors (8) in the array is 10m.
The three-component optical fiber magnetic field sensor is composed of three mutually orthogonal optical fiber magnetic field sensors adopting Faraday effect or optical fiber magnetic field sensors adopting magnetostriction effect.
The three-component optical fiber electric field sensor is composed of three mutually orthogonal optical fiber electric field sensors adopting an electro-optical absorption effect or an optical fiber electric field sensor adopting a piezoelectric elasto-optical effect.
The four-component optical fiber seismic signal sensing unit consists of four-component optical fiber vector hydrophone elements comprising a three-component optical fiber detector and an optical fiber hydrophone, and the single-vector detection element adopts a triaxial discrete structure.
The transmitting antenna (2) is: one of two mutually right-handed long wires taking a borehole as a center, a long grounding wire distributed along the radial direction of the borehole, a square large loop coil taking the borehole as a center and a round large loop coil taking the borehole as a center;
If the transmitting antenna (2) is two mutually right-handed earth long wires taking the borehole as the center or is arranged along the radial direction of the borehole, high-power pulse excitation current (3) is directly fed into the ground through the grounding electrodes at the two ends of the earth long wires;
If the transmitting antenna (2) is a square large loop coil taking the borehole as the center or a round large loop coil taking the borehole as the center; then the large power pulse exciting current (3) is connected into the square large loop coil or the round large loop coil to excite the electromagnetic field.
The second technical scheme adopted by the invention is as follows: the data acquisition method adopting the in-well array type optical fiber time-frequency electromagnetic and four-component optical fiber seismic data acquisition device (6) comprises the following steps:
a. The ground artificial seismic source (4) is sequentially excited point by point according to the seismic source points arranged around the well drilling according to the construction plan, and the four-component optical fiber seismic signal sensing unit (9) acquires full-wave-field seismic signals excited by the ground artificial seismic source point by point according to a certain point distance at a well section to be detected;
b. the three-component optical fiber attitude sensor (10) which is arranged next to the four-component optical fiber seismic signal sensing unit (9) synchronously collects three-component attitude data of the data acquisition pup joint (11);
c. the high-power electromagnetic pulse emission control device (1) continuously emits high-power electromagnetic pulse excitation current (3), and an induced electromagnetic field is excited in the ground through the emission antenna (2) so that an underground medium generates induced eddy currents which gradually diffuse and attenuate towards the half space underground;
d. The three-component optical fiber magnetic field sensor (7) and the three-component optical fiber electric field sensor (8) collect three-component magnetic field and three-component electric field data in a well point by point according to a certain point distance at a well section to be measured;
e. The data acquisition nipple (11) transmits the four-component well seismic data acquired in the step a, the three-component attitude data acquired in the step b and the time-frequency electromagnetic data acquired in the step d to an optical fiber laser signal modem in an instrument vehicle (5) on the ground through an armored optical fiber cable (12), and then the four-component well seismic data, the three-component underground magnetic field signal and the three-component electric field signal with corresponding depths are converted through modulation and demodulation;
f. C, according to three-component attitude data of a data acquisition nipple (11) acquired by a three-component optical fiber attitude sensor (10), rotationally converting the seismic data in the step e into underground four-component seismic signals with corresponding depth, and performing superposition processing and rotational conversion on the three-component magnetic field signals and the three-component electric field signals to obtain time sequence data of time-frequency electromagnetic and seismic data in the underground along the vertical direction and in two orthogonal horizontal directions parallel to the ground plane;
g. processing the time sequence three-component time-frequency electromagnetic data in the step f in a time domain or a frequency domain to obtain electromagnetic field quantity and electromagnetic field gradient of each measuring point, and extracting parameters related to the electrical property of the stratum;
h. performing inversion imaging on the electromagnetic field quantity and the electromagnetic field gradient of each measuring point in the step g to obtain a formation complex resistivity distribution change rule in a certain radial distance range of the well;
i. inversion is carried out according to the distribution change rule of the stratum complex resistivity and the relation of the stratum frequency domain complex resistivity obtained by a frequency domain processing mode, so as to obtain the distribution change rule of the stratum polarization rate;
j. And e, converting the underground four-component seismic signals into underground four-component seismic signals with corresponding depth, and performing underground seismic data processing to obtain longitudinal and transverse wave speeds, longitudinal and transverse wave impedances, longitudinal and transverse wave anisotropy coefficients, longitudinal and transverse wave attenuation coefficients, elasticity parameters, viscoelasticity parameters, seismic attribute data and high-resolution geologic structure imaging around the well.
In the step c, the waveform of the high-power electromagnetic pulse excitation current is a return-to-zero half-duty bipolar square wave or a pseudo-random pulse sequence with zero duty ratio and positive and negative polarities, and the square wave period or unit pulse width is 0.01-100 s.
In step d, each measuring point measures and records a magnetic field signal and an electric field signal of 10-50 cycles.
Further comprises: and d, calculating the anisotropic property of the complex resistivity of the stratum according to the distribution change rule of the complex resistivity of the stratum obtained in the step h, and providing the information of the occurrence of stratum and borehole deviation.
The invention has the beneficial effects that: according to the invention, the high-temperature resistant optical fiber geophone, the optical fiber magnetic field sensor and the optical fiber electric field sensor are adopted underground, and an underground optical fiber electromagnetic and optical fiber seismic data acquisition device is free of any electronic device, a moving coil type or piezoelectric type or acceleration type or MEMS type geophone, an induction coil type or fluxgate type magnetic field sensor, so that the underground array optical fiber time-frequency electromagnetic and four-component optical fiber seismic data acquisition device can acquire underground electromagnetic and underground seismic data at all heights Wen Jingli, and a data acquisition method is provided, so that the difficulty that a conventional underground electromagnetic and seismic data acquisition instrument cannot work at heights Wen Jingli is overcome; the invention has the following advantages:
1. the acquisition device greatly reduces the interference of various artificial noises on the ground to underground three-component time-frequency electromagnetic and four-component seismic data in the well, and improves the signal-to-noise ratio of the electromagnetic and seismic data in the well;
2. the method can obtain the longitudinal and transverse wave speed, the longitudinal and transverse wave impedance, the longitudinal and transverse wave anisotropy coefficient, the longitudinal and transverse wave attenuation coefficient, the elasticity parameter, the viscoelasticity parameter, the seismic attribute data and the imaging of high-resolution geologic structures around the well of the underground medium;
3. The invention can detect the formation complex resistivity distribution rule and the formation polarization rate distribution rule in a larger range around the well Duan Jing to be detected, and can also improve the resolution capability of the target geologic body;
4. The method can acquire the anisotropic characteristics of the stratum elastic wave speed and the resistivity, provide the information of the formation occurrence and the borehole deviation, and realize comprehensive interpretation and evaluation of reservoir parameters.
Drawings
FIG. 1 is a schematic diagram of a first embodiment of a borehole array fiber optic time-frequency electromagnetic and four-component fiber optic seismic data acquisition device of the invention.
FIG. 2 is a schematic diagram of a second embodiment of the in-well array fiber optic time-frequency electromagnetic and four-component fiber optic seismic data acquisition device of the present invention.
FIG. 3 is a schematic diagram of the downhole array fiber optic time-frequency electromagnetic and four-component fiber optic seismic data acquisition device of FIGS. 1 and 2.
In the figure: the system comprises a high-power generator and pulse emission control device 1, a transmitting antenna 2, a high-power pulse excitation current waveform 3, a ground artificial seismic source 4, an instrument car 5, an in-well optical fiber electromagnetic and optical fiber seismic signal receiving and collecting array 6, a three-component optical fiber magnetic field sensor 7, a three-component optical fiber electric field sensor 8, a four-component optical fiber seismic signal sensing unit 9 and a three-component optical fiber attitude sensor (optical fiber gyroscope) 10.
Detailed Description
The present invention will be further explained below with reference to the drawings in order to facilitate understanding of technical contents of the present invention to those skilled in the art.
The invention relates to an array type well three-component optical fiber time-frequency electromagnetic and four-component optical fiber seismic data acquisition device, which comprises: the underground artificial seismic source 4, the ground high-power electromagnetic pulse emission sources 1 and 2 and the underground optical fiber electromagnetic and optical fiber seismic signal receiving and collecting device 6 are connected with the instrument car 5 on the ground through the armored optical fiber cable 12, and the armored optical fiber cable 12 connected with the instrument car 5 controls the depth position of the underground optical fiber electromagnetic and optical fiber seismic signal receiving and collecting device 6 in the well;
the ground artificial seismic source 4 excites seismic waves below the ground, and the ground high-power electromagnetic pulse emission source comprises a high-power electromagnetic pulse emission control device 1 and an emission antenna 2, wherein the high-power electromagnetic pulse emission control device 1 provides high-power pulse excitation current 3 for the emission antenna 2; the transmitting antenna 2 directly feeds high-power pulse excitation current 3 into the ground through grounding electrodes at two ends of a grounding long lead, or excites an electromagnetic field through connecting a round well square large loop or a round well round large loop;
The well array type optical fiber electromagnetic and optical fiber seismic signal receiving and collecting device 6 comprises a plurality of data collecting pup joints 11, a three-component optical fiber magnetic field sensor 7, a three-component optical fiber electric field sensor 8, a four-component seismic signal sensing unit 9 and a three-component optical fiber attitude sensor 10 which are arranged in the data collecting pup joints 11; the data acquisition pups arranged in an array mode are connected through an armored optical fiber cable 12; the three-component optical fiber attitude sensor 10 in the present embodiment is an optical fiber gyroscope.
In the data acquisition nipple 11, a three-component optical fiber electric field sensor 8 is arranged at the upper end of the data acquisition nipple 11, a three-component optical fiber magnetic field sensor 7 is arranged at the lower end of the data acquisition nipple 11, a four-component optical fiber seismic signal sensing unit 9 is arranged in the middle of the data acquisition nipple 11, and a three-component optical fiber attitude sensor 10 is arranged next to the four-component optical fiber seismic signal sensing unit 9.
The four-component optical fiber seismic signal sensing unit 9 consists of four-component optical fiber vector hydrophone elements consisting of a three-component optical fiber detector and an optical fiber hydrophone, and the single-vector detection element adopts a triaxial discrete structure.
The three-component optical fiber magnetic field sensor 7 is composed of three mutually orthogonal optical fiber magnetic field sensors adopting Faraday effect or optical fiber magnetic field sensors adopting magnetostriction effect.
The three-component optical fiber electric field sensor 8 is composed of three mutually orthogonal optical fiber electric field sensors adopting an electro-optical absorption effect or an optical fiber electric field sensor adopting a piezoelectric elasto-optical effect.
Because the high-temperature resistant optical fiber detector, the optical fiber gyroscope, the optical fiber magnetic field sensor and the optical fiber electric field sensor are adopted underground, the underground optical fiber electromagnetic seismic data acquisition device is not provided with any electronic device, moving coil type or piezoelectric detector, induction coil type or fluxgate type magnetic field sensor, the underground array type optical fiber time-frequency electromagnetic and four-component optical fiber seismic data acquisition device can acquire electromagnetic and seismic data in the well to all high Wen Jingli, and the difficulty that the conventional underground electromagnetic and seismic data acquisition instrument cannot work at high Wen Jingli is overcome; electromagnetic and seismic data in the well greatly reduces the influence of electromagnetic and seismic interference of various industries and people on the ground, improves the signal-to-noise ratio of the data, can realize high-power electromagnetic emission and high-seismic energy excitation, and is beneficial to detecting exploration targets buried deeper or farther away from a receiving well.
The three-component optical fiber geophone can adopt an all-optical seismic acceleration geophone based on grating technology, is specially designed for permanent underground measurement, and can be provided with a multi-sensor array comprising an optical fiber thermometer, a pressure gauge, a multiphase flowmeter and a distributed temperature sensor system on a single optical fiber. Light propagates down the cable from the surface into the well and is reflected back to the surface, and the optical signal is converted into measurement data, which is interpreted in a conventional manner. The downhole geophones receive the seismic waves and can be processed into formation and fluid front images. Permanent downhole fiber optic 3 component (3C) seismic surveying has high sensitivity and directionality, can produce high precision spatial images, can provide not only near-wellbore images, but also images of formations surrounding the wellbore, in some cases ranging up to thousands of feet. Fiber optic seismic survey systems operate over the life of an oil well and can withstand harsh environmental conditions (temperatures up to 250 ℃ and pressures up to 30000 psi), the survey system being devoid of movable components and downhole electronics. Each 3C geophone is packaged in a1 inch diameter protective housing and can be installed into complex completion strings and small spaces. Geophones are very robust and can withstand strong shock and vibration. The fiber geophone also has the characteristics of large dynamic range and wide signal frequency band, the signal frequency band width of the system is 3-800 Hz, and the equivalent response from extremely low frequency to extremely high frequency can be recorded.
The acquisition device comprises the following two embodiments:
Example 1
Referring to fig. 1 and 3, the well array type optical fiber time-frequency electromagnetic and four-component optical fiber seismic data acquisition device comprises a ground high-power emission source control device 1, an emission antenna 2, a ground artificial seismic source 4, a well optical fiber electromagnetic signal receiving and acquisition array 6, a four-component optical fiber seismic signal sensing unit 9, an optical fiber gyroscope 10, an optical fiber electromagnetic and optical fiber seismic data acquisition pup joint 11 and an armored optical fiber cable 12. The in-well optical fiber electromagnetic and optical fiber seismic signal receiving and collecting array 5 is connected with an instrument car 5 on the ground through an armored optical fiber cable 12, and the armored optical fiber cable 12 on the instrument car 5 controls the depth position of the in-well optical fiber electromagnetic and optical fiber seismic signal receiving and collecting array 6 in the well.
The ground seismic source 4 is a ground weight source or an explosive source or a controllable source or an air gun source or an electric spark source excited in a pool.
The working principle of the underground optical fiber four-component seismic signal sensing unit 9 is as follows: the multi-wavelength modulated laser emitted from the light source light modulation system is transmitted to the underground four-component optical fiber vector hydrophone array through the multi-core optical fibers in the transmission optical cable, and the four-component optical fiber vector hydrophone loads vibration acceleration signals and sound pressure signals of the spatial position points of the four-component optical fiber vector hydrophone into corresponding laser carrier signals in an optical phase modulation mode. And uploading optical fibers through a transmission optical cable, transmitting each path of optical signals to a photoelectric receiving system, and obtaining a plurality of paths of digital carrier detection signals with optical modulation through photoelectric conversion amplification and AD conversion. And (3) restoring the four-component seismic detection digital signals with each path of high fidelity through optical modulation and demodulation.
The ground high-power electromagnetic pulse emission source comprises a high-power electromagnetic pulse emission control device 1 and an emission antenna 2. The transmitting antenna 2 is two mutually right-handed long wires taking the borehole as the center, or a long grounding wire distributed along the radial direction of the borehole and a long grounding wire distributed along the radial direction of the borehole, the length of the long grounding wire is 1000-10000 m, and the high-power electromagnetic pulse transmitting control device 1 alternately supplies power to the two long grounding wires through a reversing switch. The high-power electromagnetic pulse emission control device 1 supplies high-power electromagnetic pulse excitation current 3 to the emission antenna 2, and the emission antenna 2 directly feeds the high-power electromagnetic pulse excitation current 3 into the ground through the grounding electrodes at the two ends of the grounding long lead.
The in-well optical fiber electromagnetic signal receiving and collecting array 6 comprises one or a plurality of optical fiber electromagnetic and optical fiber seismic data collecting pup joints 11, and each optical fiber electromagnetic seismic data collecting pup joint comprises an optical fiber four-component seismic signal sensing unit 9, a three-component optical fiber magnetic field sensor 7, a three-component optical fiber electric field sensor 8 and an optical fiber gyroscope 10. The three-component optical fiber electric field sensor 8 is arranged at the upper end of the data acquisition nipple 11, the three-component optical fiber magnetic field sensor 7 is arranged at the lower end of the data acquisition nipple 11, the optical fiber four-component seismic signal sensing unit 9 is arranged in the middle of the data acquisition nipple 11, and the optical fiber gyroscope 10 is closely adjacent to the four-component seismic signal sensing unit 9. Each optical fiber electromagnetic seismic data acquisition nipple 11 is about 10 meters apart, the four-component optical fiber seismic signal sensing unit consists of four-component optical fiber vector hydrophone elements consisting of a three-component optical fiber detector and an optical fiber hydrophone, and the single-vector detection element adopts a triaxial discrete structure. The three-component optical fiber magnetic field sensor 7 is composed of an optical fiber magnetic field sensor employing faraday effect or an optical fiber magnetic field sensor employing magnetostriction effect which are orthogonal to each other. The three-component optical fiber electric field sensor 8 is composed of three mutually orthogonal optical fiber electric field sensors using an electro-optical absorption effect or an optical fiber electric field sensor using a piezoelectric elasto-optical effect. Each data acquisition nipple 6 is connected by an armored fiber optic cable 12.
Example 2
Referring to fig. 2 and 3, embodiment 2 differs from embodiment 1 in that the transmitting antenna 2 is a well-surrounding square or circular large loop centered on the borehole, the side length of the well-surrounding square large loop is 500m to 3000m, and the radius of the well-surrounding circular large loop is 500m to 1000m. Otherwise, the same as in example 1 was used.
The data acquisition method based on the array type optical fiber time-frequency electromagnetic and four-component optical fiber seismic data acquisition device (6) comprises the following steps:
a. The ground artificial seismic source 4 is sequentially excited point by point according to the seismic source points arranged around the well drilling according to the construction plan, and the four-component optical fiber seismic signal sensing unit 9 acquires direct wave signals excited by the ground artificial seismic source and full-wave field seismic signals such as reflected waves, refracted waves, diffracted waves, surface waves and the like from the stratum point by point according to a certain point distance (about 10 meters) at a well section to be detected;
b. The optical fiber gyroscope 10 which is arranged next to the four-component optical fiber seismic signal sensing unit 9 synchronously collects three-component attitude data (inclination angle ) of the data collection nipple 11;
c. The high-power electromagnetic pulse emission control device 1 continuously emits a high-power electromagnetic pulse excitation current 3, the waveform of the high-power electromagnetic pulse excitation current 3 is a zero-return half-duty bipolar square wave or a pseudo-random pulse sequence with zero duty cycle and positive and negative polarities, the square wave period or unit pulse width is 0.01-100 s, an induced electromagnetic field is excited in the ground through the emitting antenna 2, so that an induced vortex is generated by an underground medium, the induced vortex gradually diffuses and attenuates towards the half space underground, and the diffusion speed and the attenuation amplitude are related to the conductivity of the underground medium;
d. The three-component optical fiber magnetic field sensor 7 and the three-component optical fiber electric field sensor 8 collect data of the three-component magnetic field (Hx,Hy,Hz) and the three-component electric field (Ex、Ey、Ez) in the well in the step c point by point at a certain point distance at the well section to be measured, and each measuring point measures and records 10-50 periods of the three-component magnetic field signal and the three-component electric field signal in the well;
e. The data acquisition nipple 11 transmits the four-component well seismic data acquired in the step a, the three-component attitude data acquired in the step b and the time-frequency electromagnetic data acquired in the step d to an optical fiber laser signal modem in an instrument car 5 on the ground through an armored optical fiber cable 12, and then converts the four-component well seismic data, the three-component magnetic field signal and the three-component electric field signal into underground four-component seismic signals, three-component magnetic field signals and three-component electric field signals with corresponding depths;
f. C, according to three-component attitude data (inclination angle, inclination angle and azimuth angle) of a data acquisition nipple 11 acquired by the optical fiber gyroscope 10, converting the seismic data in the step e into underground four-component seismic signals with corresponding depth in a rotating way, and carrying out superposition processing and rotation conversion on the three-component magnetic field signals and the three-component electric field signals to obtain time sequence data of time-frequency electromagnetic and seismic data in the underground along the vertical direction and two orthogonal horizontal directions parallel to the ground plane;
g. processing the time sequence three-component time-frequency electromagnetic data in the step f in a time domain or a frequency domain to obtain electromagnetic field quantity and electromagnetic field gradient of each measuring point, and extracting parameters related to the electrical property of the stratum;
h. performing inversion imaging on the electromagnetic field quantity and the electromagnetic field gradient of each measuring point in the step g to obtain stratum complex resistivity distribution within a certain radial distance range of the well;
i. inversion is carried out according to the distribution change rule of the stratum complex resistivity and the relation of the stratum frequency domain complex resistivity obtained by a frequency domain processing mode, so as to obtain the distribution change rule of the stratum polarization rate;
j. And e, converting the underground four-component seismic signals into underground four-component seismic signals with corresponding depth, and performing underground seismic data processing to obtain longitudinal and transverse wave speeds, longitudinal and transverse wave impedances, longitudinal and transverse wave anisotropy coefficients, longitudinal and transverse wave attenuation coefficients, elasticity parameters, viscoelasticity parameters, seismic attribute data and high-resolution geologic structure imaging around the well.
In the step a, the ground artificial seismic source 4 is a ground weight seismic source or an explosive seismic source or a controllable seismic source or an air gun seismic source or an electric spark seismic source excited in a water pool.
In the step c, the waveform of the high-power electromagnetic pulse excitation current is a return-to-zero half-duty bipolar square wave or a pseudo-random pulse sequence with zero duty ratio and positive and negative polarities, and the square wave period or unit pulse width is 0.01-100 s.
In the step d, each measuring point measures and records a magnetic field signal and an electric field signal with 10-50 cycles.
In the step h, the anisotropic property of the formation complex resistivity is obtained according to the obtained formation complex resistivity distribution change rule, the information of formation occurrence and borehole deviation is provided, and the interpretation and evaluation of reservoir parameters are realized.
In the step i, according to the obtained formation polarizability distribution rule, the interpretation and evaluation of the formation oil-gas-containing or high-polarizability mineral parameters are realized.
In the step j, imaging of high-resolution geologic structures around the well and comprehensive evaluation of the oil and gas reservoirs are realized according to the obtained longitudinal and transverse wave speed, longitudinal and transverse wave impedance, longitudinal and transverse wave anisotropy coefficient, longitudinal and transverse wave attenuation coefficient, elastic parameter, viscoelasticity parameter and seismic attribute data of the underground medium.
Those of ordinary skill in the art will recognize that the embodiments described herein are for the purpose of aiding the reader in understanding the principles of the present invention and should be understood that the scope of the invention is not limited to such specific statements and embodiments. Various modifications and variations of the present invention will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.