TITLE:
A study on Parallel Computation Based on Finite Element Forward Modeling of 2D Magnetotelluric
AUTHORS:
Mao Wang, Handong Tan, Changhong Lin, Xiao Liu, Zhiyong Zhang
KEYWORDS:
Magnetotelluric, 2D Forward Modeling, Finite Element, Parallel Algorithm, Total Field
JOURNAL NAME:
International Journal of Geosciences,
Vol.6 No.8,
August
19,
2015
ABSTRACT: Magnetotelluric sounding
method based on the difference of the rock’s resistivity is an exploration
method about doing research in earth’s resistivity and phase using the native
electromagnetic field. The paper adopts 2D finite element method as the
magnetotelluric forward method and calculates the total field by primary field
(also named background field) plus secondary field. We canget more accurate forward result
through the finite element method and we can get the result effected by the
dense degree of grid slightly by the total field. But the method is not
effectiveenough when the model
is divided into relative big grid. When the frequency changes, program solves
relevant equation separately. According to the feature of the algorithm, we
apply MPI parallel method in the algorithm. Every process solves relevant
equation. The account of frequencythat
a process needs to solve in parallel computation is less than the account that
the processneeds to solve in
serial algorithm. We can see that the forward result is the same with the
serial algorithm and proves the correctness of algorithm. We do statistics
about the efficiency of the parallel algorithm. When the account of processes
is from 2 to 8, the speedup is from 1.63 to 2.64. It proves the effectiveness of
the parallel algorithm.