基于多面函数法的青藏高原应变特征分析

摘要

Combined the method of curve fitting when calculating a lower-frequency strain field in a large area with the strain tensor matrix on the earth reference ellipsoid,we put forward a method of calculating strain parameters on reference ellipsoid by using multi-surface function.According to the GPS data,we get the Qinghai-Tibet plateau strain field.The result is in line with both characters of the major tectonic activity within this area and the main direction of P,T-axis from focal mechanism solutions.%将曲线拟合法解算大区域低频应变分布与地球参考椭球面上的应变张量矩阵相结合,提出基于多面函数模型解算在给定参考椭球面上的均匀视应变场方法.并根据GPS实测速度场资料解算出青藏高原的均匀视应变场,解算结果与青藏高原各主要构造活动特征以及地震震源机制解所得P、T轴优势方向分布与变化规律吻合较好.认为基于旋转椭球面解算大范围均匀视应变场方法能更加精确地获取大范围内地壳形变的总体变化趋势.