基于半精度浮点数优化与OpenMP的地震数值模拟

Seismic Numerical Simulation Based on Half-precision Floating-point Number Optimization and OpenMP

研究地震波场的传播特征是地震勘探的基础,利用有限差分法求解波动方程进行地震正演,其优势在于占用内存低、计算速度快、易于实现。但在三维情况下,计算量和数据量会急剧增加,传统串行地震数值模拟将无法满足计算效率的需求。因此,本文提出一种基于半精度浮点数优化与OpenMP的三维波动方程地震数值模拟方法,该方法首先利用半精度浮点数对地震常用的浮点型数据进行优化;其次利用应用程序接口OpenMP在多核CPU下通过以分割波场计算区域的方式实现并行计算;在保证计算结果满足精度需求的同时,能有效提高三维地震数值模拟的计算效率,并减少近一半的内存需求。通过数值试验证明该方法的有效性和实用性。

Studying the propagation law of seismic wavefields is the basis of seismic exploration.The finite difference method is commonly used to solve the wave equation for seismic forward modeling,which has advantages of low memory usage,fast computation speed,and easy implementation.However,in the case of three dimensions(3D),the computational and data requirements increase dramatically and traditional,serial,seismic,numerical simulations can no longer meet efficiency demands.This study proposes a 3D wave equation,seismic,numerical simulation method based on half-precision floating-point numbers and OpenMP.This method optimizes commonly-used floating-point data in seismic calculations using half-precision floating-point numbers.It also utilizes the OpenMP application interface to achieve parallel computation on multi-core central processing units by dividing the wavefield calculation region.This strategy ensures the accuracy of the computation results while effectively improving the computation efficiency of 3D seismic numerical simulations and reducing memory requirements by almost half.The effectiveness and practicality of this method are demonstrated through numerical experiments.