42results about How to "Improve exploration accuracy" patented technology

The invention discloses a remote reference magnetotelluric impedance calculation method based on correlation detection, and belongs to the field of geophysical exploration, for overcoming the disadvantage of low accuracy of conventional magnetotelluric tensor impedance calculation. The method comprises the following steps: electric fields and magnetic fields of a base station and a reference station are respectively acquired, processed and obtained, electromagnetic field coherence degrees of the base station and the reference station are respectively calculated, when the two electromagnetic field coherence degrees are greater than a certain threshold, data segments are reserved and marked, and data segments, free from non-relevant noise interference, of the base station and the reference station are obtained; and then, magnetic field component coherence degrees of the base station and the reference station with the marked data segments are calculated, when the magnetic field component coherence degrees are greater than a certain threshold, data segments, free from noise interference, of these magnetic fields are reserved, otherwise, the data segments are abandoned, participation in subsequent tensor impedance estimation is canceled, tensor impedance estimation is carried out by use of a conventional remote reference magnetotelluric mode based on a Robust method, and apparent resistivity and impedance phase values are calculated by use of tensor estimated values. The method provided by the invention is applied to magnetotelluric exploration.

The invention provides a three-dimensional high-precision bin fractionation processing and evaluation technology for seismic data, and the method comprises the following steps: analyzing original data, and carrying out trace header modification, grid definition and linear normal moveout correction on data acquired by an observation system, thus acquiring a prestack multi-domain composite denoised image; based on the relationship between bin fractionation and the signal-to-noise ratio as well as the relationship between bin fractionation and the multiplicity during forward modeling, comprehensively compensating for the vibration amplitude, thus acquiring a tomographic inversion refracted wave static correction image; analyzing the quantitative relationship between bin fractionation and the longitudinal resolution and lateral resolution, carrying out prestack shot-domain optimized deconvolution, and carrying out azimuth restrained bin fractionation and speed optimized analysis, thus acquiring a progressive frequency-divided residual correction image; and carrying out multiple three-dimensional prestack migrations, and establishing a three-dimensional prestack migration speed model, thus acquiring a prestack migration image. Thus, the method provided by the invention provides a reliable guarantee for improving the exploration development precision and upgrading a seismic exploration technology.

The invention provides a method and a system for simulating air gun hypocenter wavelets for offshore seismic prospecting. The method includes measuring basic parameters of seawater and air gun devices; calculating a throttle constant of a gun body, an initial temperature of a gun chamber of an air gun, an initial molar mass of a gas in the gun chamber, an initial molar mass of the gas in a bubble, a molar mass of the gas in the balanced bubble, initial still water pressure, an initial radius of the bubble, an initial volume of the gas in the bubble and a bubble balancing radius; determining a function of a temperature time history of the bubble in the vibration process of the bubble, a function of a molar mass time history of the gas in the bubble and a function of a volume time history of the gas in the bubble; simulating a time history seawater viscosity; simulating a pressure wave produced by the bubble in consideration of the seawater viscosity and a ghost reflection pressure field; using the pressure wave produced by the bubble to simulate a ghost reflection pressure wave of the pressure wave; and overlying the pressure wave produced by the bubble and the ghost reflection pressure wave to synthesize the air gun wavelets. By means of the method and the system, the consistency of simulation wavelets and actual measurement wavelets is enhanced.

The invention relates to a velocity and acceleration two-parameter digital geophone, so that a problem that surveying accuracy is poor in the prior art can be solved. A micro electromechanical system acceleration transducer and a moving-coil velocity detector are integrated into one to form a digital detector that is capable of simultaneously collecting two physical quantities: velocity and acceleration of a same receiving point and has functions of signal collection and reception of velocity and acceleration at a same receiving point; therefore, subsequent data processing and analyzing can be carried out in fields of velocity and acceleration that are different physical quantities for describing displacement of the same receiving point and then comparison and analyzing are carried out. The digital geophone has advantages that: a seismic wave spreading characteristic can be studied precisely and surveying accuracy can be improved.

The invention provides a transient electromagnetic transmitting coil self-induction signal eliminating method and device. The method includes the following steps that: a rectangular loop source is adopted to detect secondary induction transient electromagnetic field data of an area to be estimated with predetermined observation parameters; transmitting coil self-induction signal transient electromagnetic field data are obtained based on the predetermined observation parameters; and the difference value of the secondary induction transient electromagnetic field data and the transmitting coil self-induction signal transient electromagnetic field data is calculated, and the interference of transmitting coil self-induction signals are eliminated according to the difference value, so that the electromagnetic induction signals of the area to be estimated can be obtained. With the method and device adopted, the degree of distortion at an early stage is reduced, and exploration accuracy is improved.

The invention provides a method for correcting diurnal variation of a natural electric field. As for the method, natural electric field measuring equipment is adopted to collect natural electric fieldsignals of a known geological point at a certain time interval, according to the natural electric field acquisition time, frequency and other parameters, a formula is adopted to correct natural electric field data of other measuring points, wherein the formula is F<n>(f)=(U<n>(T<n>,f)-U<0>(T<n>,f)*L<0>/U<0>(T<n>,f)/L<n>, thus the random change and interference of the natural electric field signals are eliminated, the geological conditions of the measuring area is more truly reflected, the quality of the natural electric field data in the whole measuring area is improved, and the exploration effect is improved.

The invention discloses a method of exploring morphological characteristics of a gorge bank slope deep-buried underground large karst cave. According to the method, through excavating a horizontal exploratory cave to the karst cave at the gorge slope, if the karst cave is a filled karst cave, the tail-end section of the exploratory cave is expanded to form an operation room, the operation room is internally provided with a geological drilling rig for karst cave exploration operation, and if the karst cave is a half-filled or non-filled karst cave, the horizontal exploratory cave only needs to be communicated with the karst cave. karst cave filling material can be sampled, analyzed and tested in a near distance, and on the basis of improving the karst cave exploration precision, the drilling engineering quantity and the exploration fee can be saved obviously, and the exploration period is shortened.

The invention discloses an array antenna source for advanced transient electromagnetic tunnel forecast. The array antenna source comprises multiple emission units, wherein the back of each emission unit is an external power source, the emission units respectively comprise an emission antenna, a spiral wire and a foundation, the spiral wire is wound at periphery of the emission antenna, an isolation layer is arranged between the spiral wire and the emission antenna to prevent current contact, the mutual inductance elimination effect is further realized, one side of a recess portion of a foundation center is an access port of the external power source, the other side of the access portion is provided with a needle array used for plugging the emission antennas, and periphery of the foundation has corresponding projections and recesses which are used for splicing the multiple emission units into one body. According to the array antenna source, emission field source intensity can be improved through changing source parameters and emission current intensity, exploration depth is improved, emission source pulse width is changed, high frequency harmonic wave components are improved, exploration precision is improved, high-resolution long distance exploration can be realized, and precise detection on a water guide channel in front of a tunnel face can be realized.

The invention provides an observation system optimization method and device for signal-to-noise ratio consistent energy illumination of a target layer. The method comprises the steps that a near-surface signal-to-noise ratio library is established; a target layer illumination result is combined on the basis of the near-surface signal-to-noise ratio library to form a signal-to-noise ratio illumination analysis result based on the target layer; and consistency processing is carried out on the illumination result to optimize an observation system. According to the invention, the signal-to-noise ratio weight factor is added on the basis of conventional target layer ray illumination; in addition to considering the influence of a velocity field on the illumination, the influence of factors suchas near-surface structure, lithology, excitation parameters and surface fluctuation elevation on the illumination result are mainly considered; the design optimization of the observation system basedon the signal-to-noise ratio consistent energy illumination of the target layer is more in line with the actual situation, and can better guide the design and evaluation of a field observation system;and collected seismic data have higher energy and signal-to-noise ratio, which ensures the data quality and improves the exploration accuracy.

The invention relates to the technical field of magnetic exploration, and discloses a device for surveying the position of a magnetic mine according to underground magnetic field distribution. The device comprises a ship body, a support is hinged to the bottom of the ship body, a wire is inserted into the support, the outer side of the wire is fixedly connected with a bottom plate, a sliding block is hinged to the inner wall of a swing rod, a driving lever is welded to the inner top of the support, an electromagnet is fixedly connected to the inner wall of a transmission wheel, an ejector rod is slidably connected to the inner bottom of the transmission wheel, and a friction plate is hinged to the inner bottom of the transmission wheel. According to the device for surveying the position of the magnetic mine according to the underground magnetic field distribution, a counterweight mechanism descends to drive a roller to descend, the roller rotates under the action of friction force of the wire, the roller rotates to drive a worm to rotate, the worm drives a worm gear to rotate, the worm gear drives a cutting ring to rotate, and the cutting ring and the counterweight mechanism are used in cooperation, so the effects of equipment blockage prevention and stable operation are achieved.

The invention discloses a moving coil detector for simultaneously detecting speed and acceleration. The moving coil detector for simultaneously detecting speed and acceleration is based on a traditional moving coil detector structure, two large flat plate electrodes are arranged above and below a moving coil moving part as a moving capacitor, and one flat plate electrode is respectively arranged on the upper surface and the lower surface of the inner side of a shell as a fixed polar plate, so that a capacitor is respectively formed on the upper part and the lower part of a moving coil to formthe structure of a capacitive accelerometer; two side surfaces of the moving coil are also respectively provided with a capacitor polar plate as a moving polar plate, and the position of the inner wall of the corresponding shell is also provided with a capacitor flat plate as the fixed polar plate, so that two capacitors are formed on the side surface of the moving coil; the upper capacitor and the lower capacitor are connected with the subsequent detection circuit. The beneficial effect of the moving coil detector for simultaneously detecting speed and acceleration is that the double-parameter acquisition and reception of the speed and the acceleration of the same receiving point can be achieved, weak signals can be detected, the propagation characteristics of the seismic waves can be studied more finely, and the exploration precision can be improved; the system structure is simple and the sensitivity is high.

The invention provides a transient electromagnetic step response acquisition method, which comprises the following steps of: performing full-time sampling and recording on any transient electromagnetic emission waveform and response to obtain transient electromagnetic full waveform and transient electromagnetic full waveform response; discretizing the transient electromagnetic arbitrary transmitted waveform by adopting a pulse waveform, and obtaining a relational expression of transient electromagnetic arbitrary waveform response and transient electromagnetic step response after concluding and recurring a discretized result; transient electromagnetic arbitrary waveform response can be converted into step waveform response by adopting the relational expression. According to the method for acquiring the transient electromagnetic step response, the transient electromagnetic step response under an ideal condition can be acquired, so that the exploration precision is improved.