Fast calculation of isostatic compensation correction using the GPU-parallel prism method

Abstract

Isostatic compensation is a crucial component of crustal structure analysis and geoid calculations in cases of gravity reduction. However, large-scale and high-precision calculations are limited by the inefficiencies of the strict prism method and the low accuracy of the approximate calculation formula. In this study, we propose a new method of terrain grid re-encoding and an eight-component strict prism integral disassembly using a compute unified device architecture parallel programming platform. We use a fast parallel algorithm for the isostatic compensation correction, using the strict prism method based on CPU + GPU heterogeneous parallelization with efficient task allocation and GPU thread overloading procedure. The results of this study provide a rigorous, fast, and accurate solution for high-resolution and high-precision isostatic compensation corrections. To ensure an absolute calculation accuracy of 10−6 mGal, the maximum acceleration ratio of the calculation was set to at least 730 using one GPU and 2241 using four GPUs, which shortens the calculation time and improves the calculation efficiency.