恭城—栗木断裂带的应变特征与变形环境探讨

The Strain Characteristics and Deformation Environment Discussion of the Gongcheng—Limu Fault Zone

通过系统的有限应变测量与差异应力估算,探讨了恭城—栗木断裂带的应变特征与变形环境,以其推动该断裂带的研究向更深层次发展。结果表明:①付林指数K的变化范围为0.32～1.67;应变主轴平均方位为276°∠21°,与断裂带的整体逆冲方向基本一致;断裂带的平均应变程度为2.26～3.00,属中等应变程度;断裂带的应变类型属压扁型应变与单剪型平面应变的一种复合叠加类型。②断裂带的差异应力值为40～80 MPa,变形深度小于10 km,属半脆性—半韧性的变形域。③断裂带的应变特征与变形环境及宏观构造样式基本吻合。

The strain characteristics and deformation environment of Gongcheng—Limu fault zone were discussed based on the finite strain analysis and differential stress estimation in this paper.The analysis results indicate：①The change scope of Flinn parameters（K） is between 0.32 and 1.67;the average strain principal axis is 276°∠21°which is consistent with the whole thrust direction of the fault zone;the average strain degree of the fault zone ranges from 2.26 to 3.00;The strain type of the fault zone is a superimposi-tion style composing of flattening strain and plane strain of simple shear.②The differential stress value is 40-80 MPa.The deformation depth of the fault zone is less than 10km and belongs to the half brittleness-half toughness deformation domain.③The strain characteristics coincides with deformation environment and macroscopically structural style of the fault zone.