Three-dimensional numerical simulation method of time-domain ground-space transient electromagnetic under complex terrain

Abstract

The invention relates to a time-domain ground-space transient electromagnetic three-dimensional numerical simulation method under complex terrain. The non-uniform grid is used to subdivide the air layer and undulating terrain in the calculation model, and the first-order Gaussian pulse derivative is introduced as a virtual emission source into the explicit finite difference iterative calculation, which avoids the cumbersome process of calculating the initial field, and uses a virtual The field soft source loading method, the electromagnetic field has stronger propagation and penetration capabilities, and can realize electromagnetic numerical calculations with a longer time window; finally, by loading the CFS-PML boundary condition in the virtual wave field, the electromagnetic wave in the virtual wave field is analyzed according to the transmitting and receiving distance. The reflection coefficient and surface wave absorption characteristic parameters are adjusted, which effectively solves the problem of large calculation errors where the emission source is located at the boundary of the region, and provides the optimal parameter selection scheme, which realizes the single-side full region of the electric source under complex geological conditions. Time-domain, ground-space, three-dimensional electromagnetic high-precision simulation. The problem of time-domain ground-space transient electromagnetic simulation calculation under complex geological conditions is solved.

Description

technical field [0001] The invention relates to a time-domain ground-space transient electromagnetic three-dimensional numerical simulation method under complex terrain, in particular to a long wire source ground-space transient electromagnetic three-dimensional numerical simulation method. Background technique [0002] Transient electromagnetic ground-air system (Air-ground transient electromagnetic method system), also known as transient electromagnetic semi-aerial system, is to place the electrical emission source or magnetic source on the surface, and use helicopter or UAV to receive in the air to realize ground launch, An electromagnetic measurement method received over the air. Compared with ground TEM and aviation AEM, the ground-air system reduces the load on the helicopter, realizes large emission magnetic moment, high-altitude detection, and improves the exploration depth. [0003] The transient electromagnetic method is an underground near-surface detection metho...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to address the deficiencies of the above-mentioned prior art, to provide a three-dimensional numerical simulation method of time-domain ground-space transient electromagnetic under complex terrain that effectively solves the problem that the emission source is located at the boundary of the region and the calculation error is relatively large

It effectively solves the problem of large calculation errors where the emission source is located at the boundary of the region, and finally realizes the time-domain, ground-space, three-dimensional electromagnetic high-precision simulation of the entire area on one side of the electrical source under complex geological conditions

Images