Three-dimensional gravity magnetic multiple acquisition method

Abstract

The invention relates to geophysical exploration technology, in particular to a three-dimensional gravity magnetic multiple acquisition method for ground gravity and ground magnetic exploration. The method comprises the following steps: performing three-dimensional flanging measurement supplementation on the edge of the periphery of a three-dimensional target work area, making an edge distance equal to the depth of a target object, and distributing measuring points by amplifying the point distance of the target work area by 1 to 1.5 times; and designing and distributing three-dimensional gravity and magnetic check control lines, repeatedly measuring the three-dimensional gravity and magnetic check control lines in a reciprocating way, checking the observation precision of the measuring points, repeatedly measuring three-dimensional measuring points by orthogonal or imbrication propelling or reciprocating observation, and performing auxiliary observation on the gravity and magnetic measuring points in an interference area. The method can acquire three-dimensional gravity and magnetic inverse spatial data, makes the three-dimensional gravity and magnetic data form a three-dimensional data body which has low random observation error and no strangeness and effectively suppresses near-surface distortion, and improves the 1:50,000 scale gravity and magnetic acquisition observation precision to 0.014mgal and 0.9nT.

Description

technical field [0001] The invention relates to geophysical exploration technology, in particular to a three-dimensional gravity-magnetism compound acquisition method for ground gravity and ground magnetic force exploration. Background technique [0002] The currently used ground gravity and magnetic acquisition method is an area-based single-observation gravity-magnetic acquisition method. The usual area-based acquisition method for gravity and magnetic exploration in the oil exploration industry is to observe the coordinate points (common points) in the work area using a single observation method without repeated observations. No data collection will be done for areas outside the boundary of the work area. Gravity general point observation is a single observation method, that is, the observation sequence of an observation unit is "base point A, general point 1, general point 2, ..., check point, ..., general point n, base point B". The accuracy of this acquisition method ...

AI Technical Summary

Problems solved by technology

The accuracy of this acquisition method is relatively low (the observation accuracy of 1:50,000 gravity data acquisition is generally 0.040mgal, and the observation accuracy of magnetic data is 2.0nT), the ratio of checkpoints to common points is low (5%), and the distance between base points is large. The general point accuracy is greatly affected by random errors, error transmission and accumulation are inevitable, and singular points (jump points) are prone to appear, and the boundary influence is not considered, and no measuring points are deployed outside the boundary of the study area

This acquisition method is only suitable for conventional exploration targets, and it is difficult to further improve the accuracy of gravity and magnetic exploration

[0003] The shortcomings of boundary truncation, low inspection rate, error transmission and accumulation, large random errors, and prone to singular points in conventional area exploration make the collected data unable to meet the needs of 3D gravity and magnetic inversion processing.

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