GEOPHYSICAL EXPLORATION METHOD

摘要

The geophysical exploration method involves synchronous measurements of an intensity of the natural pulsed electromagnetic field of the Earth (NPEFE) in different parts of the area being explored with all measurements are taken in a range of very low frequencies in at least two different directions to receive a signal by routing and reference devices, and first the sensitivity and identity of reception of signals by all routing and reference devices are adjusted, the antennas for the same reception channels of all involved devices are oriented in same preset directions of space, the graphs with spatial changes in the intensity of fields along the work profile are construed, any geophysical anomaly is identified in the profile being explored, with measuring available structural and lithological heterogeneities by an anomalous change in the intensity of NPEFE, the boundaries of anomalies are mapped and the results are given a geological interpretation. The routing devices for measurement of the electromagnetic field for subsequent compensation of noises from local and remote sources are additionally installed, at least two routing devices are installed in each peg, the profiling is made with simultaneous measurement of signals by all routing and reference devices with the preset discreteness, the digital filtering is provide for selection of signals in the context of noise, the group processing is given to signals from routing and reference devices by setting admissible ranges for factors of cross-correlations between signals of the corresponding channels of different routing devices, different routing and reference devices, a time interval is set for calculations of factors of cross-correlations for signals, calculations of factors of cross-correlations between signals from the corresponding channels of routing devices and between signals of the corresponding channels of routing and reference devices, values of each calculated factor of cross-correlations for each routing devices are compared with corresponding admissible ranges of factors for cross-correlations of signals, with further determination of a signal from the routing device as a NPEFE signal in the point of current location of the routing device, if the values of the calculated cross- correlation factors correspond to the preset corresponding admissible range of cross-correlation factors, then a number of signals determined as NPEFE signals is calculated in each point of current locations of the corresponding routing device for each corresponding device within the time interval in accordance with the preset discreteness of signal measurements, and the intensity of NPEFE in those points is determined for the further mapping of the boundaries of geophysical anomalies, on the basis of the intensity value of NPEFE in different points of the area being explored.