电法勘探正演数值模拟的若干结果

本文前一部分叙述了点源二维电阻率法数值模拟正演计算的有限单元法,文中采用混合边界条件、用LL~T分解解线性方程组等优化措施,使二维有限单元法电阻率法正演计算的速度和精度都比目前国外流行的L.Rijo方法和程序有了进一步的提高。文中介绍了有关的方法并引入了若干计算结果。本文后一部分叙述了三维电阻率法数值模拟的积分方程近似解法,由于对K.Dieter等人提出的方法作了一些近似处理,并用迭代法求解积分方程表示式,实算结果说明在保证计算精度的条件下,提高了计算速度,从而提高了三维电场正演计算的有效性和实用性。所提出的方法容易推广到激发极化法的正演计算中。

SOME RESULTS OF RESISTIVITY MODELLING

In the first part of this paper a finite element method for two-dimentional resistivity modelling is developed. We applied the mixed boundary condition and the LLT decomposition for solution of the equation system and designed a optimization programme-The results of computation show that the programme is better in temrs of the velocity and the accuracy of computation than L. Rijo's programme.In the second part of the paper an approximate method for solving the integral equation of three-dimentional resistivity modelling is discussed. The iterative method for calculating the integral equation is applied. The results of computation show that this algorithm is faster than the algorithm proposed by K. Dieter et al.