2717 results about "Seismic wave" patented technology

Methods are disclosed employing seismic waves having infrasonic frequencies in the range of about 0.1–20 Hz for generating electromagnetic waves of similar infrasonic frequency in hydrocarbon bearing subterranean formations located at depths up to about 5000 meters, said electromagnetic waves having sufficient voltage amplitudes for detection at the earth's surface. Also disclosed are seismic sources capable of generating infrasonic seismic waves of sufficient amplitude for generating electromagnetic waves in hydrocarbon bearing formations at depths up to 5000 meters, said electromagnetic waves having voltage amplitudes sufficient for detection at the earth's surface.

A method and device for seismic exploration of a subsea geologic formation by pickups set on the sea bottom and intermittently connectable to active data acquisition stations (11) brought nearby. Permanent passive reception stations (1) comprising a heavy pedestal provided with housings for seismic pickups (geophones (6), hydrophone (7)) which receive acoustic or seismic signals from the underlying formation are arranged at the bottom of the water body. When collection sessions for the signals received by the pickups are scheduled, mobile active acquisition stations (11) connected to permanent passive reception stations (1) are positioned at the bottom of the water body. The signals picked up are then recorded, for the time required to carry out at least one session of acquisition and recording of the acoustic or seismic signals received by the passive stations in response to the emission of seismic waves by one or more seismic sources. The mobile active acquisition stations (11) are thereafter recovered at the surface and the records acquired by each one are transferred to a central collection laboratory.

Ocean bottom seismic cables are subject to rolling motions due to seismic wave fields and current action which cause poor receiver ground-coupling and signal distortion, particularly along the cross-line and vertical axes. Two multi-axial receivers are mounted on opposite sides of the cable in a single cluster. When the cable rolls, the axial response of one receiver of the cluster cancels the axial response of the other receiver of that cluster.

The invention belongs to petroleum geophysical prospecting, and relates to a method for defining effective thickness of a target reservoir bed under complex geological conditions, by which the reservoir thickness is confirmed by using seismic wave information (namely, characteristic points and amplitude information). The method comprises the following steps: selecting comprehensive seism and logging information of a target layer section in a studied work area; obtaining a stack profile section after conducting Hi-definition and high resolution process on seism data; then meticulously explaining the position of the layer; and finally performing thickness prediction on the target reservoir bed. By the adoption of the invention, the effective thickness of the target reservoir bed under complex geological conditions can be estimated; and the method is not only suitable for conditions of each thin layer, and but also suitable for conditions that thickness, net sand ratio, thickness of various single layers and distribution manner of an actual thin alternating layer are all intensely changed, is not limited by tuning thickness of the thin layer, and has stronger adaptability.

The invention relates to a direct prestack time migration method for the seismic data acquired under the undulant ground surface. The method is applied to reflection seismic data processing during earthquake exploration and is a prestack migration imaging method aiming at the seismic data acquired under the undulant ground surface. The method can be directly applied to the seismic data which is acquired under the undulant ground surface and is acquired at shot points and demodulation points of different heights. Accordingly, the method can avoid errors caused by field static correction processing as well as correct the speed of a speed reducing belt in a migration process. The method can self-adaptively determine time-varying migration aperture and can correctly compensate geometric spreading effect of seismic waves during an imaging process so as to obtain an amplitude-preserved common reflection point gather. The core of the method is to use a one-way wave theory and a stable phase point principle to analyze so that the travel time and the amplitude of the seismic waves, which depend on the speed and thickness of the speed reducing belt, the heights of the shot points and the demodulation points, and stacking speed based on a floating datum plane, are obtained. The method has important application value for the explorations of oil, gas and mineral resources in areas with complex ground surfaces.

The invention includes a geographical sensor apparatus for use under water in the sea, including a plurality of seismic sensors (1) for sensing seismic waves associated with underground formations, and a plurality of EM-sensors constituted preferably by electrodes (4) for sensing electromagnetic waves associated with the underground formations. In a preferred receiver cable configuration embodiment of the invention, the geophysical sensor apparatus includes a seismic receiver cable with a linear array of a plurality of seismic sensors (1) and EM-sensors arranged inside a flexible outer skin (25), with the EM-sensors having electrodes on the outside of the outer skin. The cable is operated on the seafloor by a surface vessel, the vessel towing an electromagnetic transmitter antenna in addition to the seismic source.

The present invention presents a comprehensive advanced geological detection system carried on a tunnel boring machine. The comprehensive advanced geological detection system includes a multifunctional combination main frame, an induced polarization detection device, a seismic wave detection device, an integrated junction device, a borehole ground penetrating radar detection device and a comprehensive interpretation and decision system; the multifunctional combination main frame includes a time division multiplexing control module, an excitation source control module and a parallel data acquisition module; the excitation source control module outputs trigger signals to the three detection devices respectively, and the three detection devices respectively output measurement data and feedback signals to the time division multiplexing control module through the parallel data acquisition module; and the comprehensive interpretation and decision system supports geological interpretations and decisions through the inversion/migration imaging joint inversion of three detection methods.

The invention discloses an elastic reverse time migration imaging method by combining seismic multi-component and belongs to the field of exploration geophysics. The method comprises the following steps: directly inputting seismic multi-component data; without performing the wave field separation on the input data, extrapolating forwards at inverse time based on an elastic wave equation; building an underground elastic vector seismic wave field by combining with multi-component; acquiring four elastic wave imaging results having specific physical significance, such as longitudinal wave, transverse wave, transition longitudinal wave and transition transverse wave, by applying an elastic wave cross-correlation imaging condition of lighting compensation; and suppressing the low wave number noise in the elastic reverse time migration by performing low-pass angle filtering, thereby acquiring an imaging result of final elastic wave migration. By directly inputting the seismic multi-component data and building the underground elastic vector seismic wave field by combining with multi-component, the method can be used for accurately imaging for complex earth medium.

An energy-based method for automatically locating the earthquake focus of a microearthquake belongs to the field of microearthquake detection, and relates to an earthquake focus locating method used in a microearthquake monitoring system, in particular to an automatic microearthquake locating method and a method for improving the locating accuracy. The invention adopts an earthquake wave dynamic method which is an earthquake locating algorithm based on earthquake wave energy attenuation equation, complicated calculation of energy of the earthquake waves is not required, parameters such as themaximum shake amplitude or quadratic sum of the shake amplitude and the like are adopted to represent energy, and the arrival time of the earthquake waves does not need to be picked up at all, so that problems caused during automatic locating of the earthquake focus of the microearthquake are solved; and as energy difference is taken as the optimized variable, while energy attenuation is in direct correlation with range, the defect that the travel-time difference serving as the optimized variable is only related to the travel-time difference (range difference) but not in direct correlation with the size of the range per se, the external-field locating accuracy, particularly the accuracy in the vertical direction, is improved, and the stability of the locating result is also improved.

The invention is a seismic emission device designed to be immersed at the bottom of a water body (sea, lake, etc.), and method of implementation. The device comprises at least one (and preferably several) self-contained emission units (1) immersible at the bottom of a water body, combining at least one or more seismic wave sources (8), such as air guns for example, suited to be placed in contact with the body, local energy storage (9) which supplies the device a multifunction connection cable (5) connecting each self-contained emission unit to a surface relay unit (4), a communication system (4a, 6a, Y) providing communication with a central control station (6) located for example on a drilling or production platform (3). VSP repetitive exploration operations can be carried out in a well by activating successively the various emission units and by acquiring the signals picked up by receivers R1-n placed in a well for example and coupled with the formation. The device can be used for oil prospecting.

The invention provides an earthquake physical model and a preparation method and application thereof. The materials of the earthquake physical model comprise main materials, auxiliary materials and aids, wherein the main materials are epoxy resin and rubber, and the aids are curing agent, cross-linking agent, diluent, defoaming agent and the like. A novel earthquake physical model material is synthesized by special preparing equipment and processes and used for building an earthquake physical model according to a similarity principle to simulate a real geological structure; and the earthquake physical model can be used for research on seismic wave field and researches for other purposes, particularly used for researching kinematics and kinematic characteristics of seismic waves propagating in complicated areas; moreover the earthquake physical model can provide objective bases for verification of new methods and new theories in oil-gas exploration and development.

The invention provides a model constraint based impedance inversion method and a model constraint based impedance inversion system. The model constraint based impedance inversion method includes: acquiring log data, seismic data and acquisition matrixes of a current stratum; extracting seismic interpretation data from the seismic data; building an initial impedance model according to the log data and the seismic interpretation data; estimating seismic wavelets according to the log data and the seismic data; confirming objective function according to relationship between acoustic wave impedance and reflectance and sampling relationship when seismic traces are missing; confirming impedance sections or impedance objects of the current stratum according to the initial impedance model, estimated seismic wavelets and the objective function; and comprehensively interpreting the impedance sections and the impedance objects to acquire reservoir prediction results of the current stratum. Through model regularization, seismic data interpolation and seismic wave impedance inversion are combined organically, so that the seismic data interpolation and the seismic wave impedance inversion can be realized simultaneously.

This invention disclose a kind of high resolution nonlinear reservoir object inversion method, uses a kind of nonlinear reservoir lithologic object convolution module to build the function relation of wave impedance and porosity/ argillaceous content; describes the physical relation of complex rock by analyzing multilevel structure and determining two-way edge wavelet; realizes the combination of the certainty inversion, statistic inversion and nonlinear theoretics; then realizes the high resolution reservoir object parameter inversion of composite geology, well logging and earthquake wave impedance information base on both inverse operator inversion and positive operator reconstructed algorithm, gets high resolution reservoir object cross section (such as porosity, argillaceous content).

The invention is a seismic wave impedance inversion method, determining amplitude and phase spectrums of pos-stack seismic data, and extracting seismic subwaves on a near-well seismic channel and determining amplitude and phase spectrums, spectrum widths and master frequencies of the seismic subwaves; picking up seismic stratigraphic horizons corresponding to geological stratigraphic horizon and checking and correcting as well as smoothing and interpolating the picked horizons; demarcating logging acoustic time difference and density curves, and demarcating depth-domain logging acoustic time difference and density curves into time-domain ones, consistent with horizons of stacked seismic data, generating in-well wave impedances; making wavelet odd analysis and wavelet characteristic extraction on the stacked seismic data; providing high resolution wave impedance parameters for reservoir description in the exploration, development and recovery of oil fields.

A method, system and a marine node for recording seismic waves underwater. The node includes a body made of a compressible material that has a density similar to a density of the water; a first sensor located in the body and configured to record pressure waves; and a second sensor located in the body and configured to record three dimensional movements. The body is coupled to the water for passing the seismic waves to the first and second sensors.

The invention relates to a seismic wave absorption and attenuation compensation method, and belongs to the geophysical exploration data processing technology. The method comprises the following steps: selecting one of VSP (vertical seismic profiling) initial data as reference data, carrying out generalized S-transform on the reference data, selecting sampling points as reference points, and recording the time and time-frequency spectrums of the sampling points; carrying out generalized S-transform on data of each sampling point, and dividing the time-frequency spectrum of corresponding frequency in the time-frequency spectrums of the reference points by the time-frequency spectrum of each sampling point so as to obtain an absorption and attenuation curve; determining a natural logarithm to figure out a phase compensation operator according to a formula of frequency difference of absorption and attenuation signals in a time frequency domain; and carrying out absorption and attenuation compensation and phase compensation in the time frequency domain to obtain a fine VSP wave field profile. The method has the advantages that noise can be eliminated during the process of fitting the absorption and attenuation curve; generalized S-inverse transform without energy loss is realized; signal-to-noise ratio and resolution of the data are improved after compensation; log resolution control is realized; the reference points are selected flexibly; and algorithm is simple and efficient.

The invention discloses a tunnel boring machine active source three-dimensional seismic advanced geology exploration device and method. The device comprises a tunnel boring machine cutterhead and a tunnel boring machine body connected with the cutterhead, wherein a main control room is arranged in the tunnel boring machine body; a controller and a multichannel seismic wave data collecting instrument are arranged in the main control room; seismic source systems are respectively arranged at the front ends of the tunnel boring machine cutterhead and the tunnel boring machine body; a data collecting system is arranged at the rear part of the working surface of the tunnel boring machine body according to certain space observation mode; the controller is respectively connected with the multichannel seismic wave data collecting instrument, the seismic wave systems and the data collecting system; the multichannel seismic wave data collecting instrument is connected with the data collecting system. The device has the benefits that rapid, flexible and automatic arrangement of a seismic wave and a detector system is realized, the maintenance time of the tunnel boring machine is sufficiently utilized, the work efficiency of geological advanced prediction is greatly improved, the normal construction is not disturbed, and time cost and economic cost are saved.

The invention relates to a simple multi-parameter seismic inversion method for improving the precision and the reliability of the conventional pre-stack seismic inversion with the help of the seismic wave elastic impedance, thereby simultaneously extracting a variety of formation parameters. The steps are as follows: full wave logging information is utilized; an acoustic impedance AI and an elastic wave impedance EI are determined; a CMP gather is converted into an angle gather, and part of the angles are stacked; the conventional pre-stack elastic impedance inversion process is utilized to respectively carry out the AI and the EI inversion of cross-well measuring line of small angle stacked data and part of the stacked data of the middle incident angles; the channel calculation of the EI and the AI data which are obtained by inversion is carried out, thereby obtaining the seismic attributes which are closely related to the elastic density ratio, the lithology changes and the pore fluid ingredients; the reservoir lithology and the properties of the pore fluid are determined. The simple multi-parameter seismic inversion method only needs the seismic data of near and middle angles, and other parameters are obtained through the channel calculation of the relationship between the elastic density ratio and the acoustic impedance, thereby improving the calculation efficiency and being used in the pre-stack inversion of the seismic data obtained by the vast majority of the collection conditions.

The invention provides an underground engineering construction advanced geological prediction system and a prediction method thereof which comprise earthquake wave receivers that are distributed in the underground construction tunnels and the arrangement method thereof, an earthquake wave collector and an earthquake wave data processing and analyzing system, wherein, the earthquake wave collector is formed by connecting a system motherboard and 16 collecting daughter boards in a way of inserting card, and the daughter boards are communicated with the system motherboard by connecting sockets to obtain electricity; the system motherboard comprises an SCM master-control circuit, a power, a power light, a serial port, a USB port and a wireless port; each collecting daughter board comprises a connecting socket used for connecting with the motherboard, and a field programmable gate array circuit FPGA; the earthquake receiver is a multi-component spatial receiver, which comprises a detector and a supporting carrier for the detector; the earthquake wave data processing and analyzing system is a computer in which an earthquake wave data processing and analyzing software is installed. The system can detect the shape of spatial 3D geologic body, improves the reliability and accuracy of construction advanced geological prediction, is used for underground engineering construction advanced geological prediction and applicable for various underground engineering excavations, furthermore, shot points and receivers of this system can be flexibly arranged.

The invention discloses a tunnel construction large-scale integrated geophysics advanced detection model test device, which comprises tunnel surrounding rock, a main tunnel model, a model test case, a water-containing geological structure device, a numerical control automation construction device and a main control chamber. The model test device is a large-scale integral geophysics advanced detection model test device meeting the detection of a seismic wave method, an electromagnetic method and a direct current power method, the geophysics advanced detection model test device can be utilized for studying the geophysics response characteristics of the water-containing geological structure device in front of a tunnel face, in addition, various geophysics advanced detection forward and inversion methods of the water-containing geological structure device are verified, the relationship between some geophysics detection method results and the water inflow is studied, and the test foundation is laid for the water inflow prediction and the advanced prediction of the water-containing geological construction device in actual engineering.