CAJ | 학술논문

台湾海峡两岸存在一系列断续分布、横贯台湾海峡的NW向断裂,研究表明为一系列具有走滑运动的横向构造,根据地壳运动、区域变形和断裂特征分为巴士断裂带、台中-晋江断裂带和宁德-三貂角断裂带.中部的台中-晋江断裂带是一条控制地壳运动南北差异的重要分界断裂,断裂带以北的东南沿海北部和台湾北部地壳整体向东运动,与琉球俯冲带右行走滑运动方向基本相同,形成一致的变形取向;断裂带以南处于华南地块与菲律宾海板块相向运动挤压变形环境,地壳变形比北部强烈.东南沿海地震强度增强趋势、地震南强北弱与该应变场和横向走滑有关:(1)由于该断裂以南比以北地区应力应变场变化大,多场耦合复杂,耦合程度降低,造成蠕动变形不均产生应力闭锁,孕育地震发生.(2)福建东部比台湾海峡地壳均一性差、地球物理场变化明显,组成更为复杂的多元、多场耦合,耦合场稳定性差,容易受横向构造活动干扰,产生弹性变形而孕育地震强度增强.
태만해협량안존재일계렬단속분포、횡관태만해협적NW향단렬,연구표명위일계렬구유주활운동적횡향구조,근거지각운동、구역변형화단렬특정분위파사단렬대、태중-진강단렬대화저덕-삼초각단렬대.중부적태중-진강단렬대시일조공제지각운동남북차이적중요분계단렬,단렬대이북적동남연해북부화태만북부지각정체향동운동,여류구부충대우행주활운동방향기본상동,형성일치적변형취향;단렬대이남처우화남지괴여비률빈해판괴상향운동제압변형배경,지각변형비북부강렬.동남연해지진강도증강추세、지진남강북약여해응변장화횡향주활유관:(1)유우해단렬이남비이북지구응력응변장변화대,다장우합복잡,우합정도강저,조성연동변형불균산생응력폐쇄,잉육지진발생.(2)복건동부비태만해협지각균일성차、지구물리장변화명현,조성경위복잡적다원、다장우합,우합장은정성차,용역수횡향구조활동간우,산생탄성변형이잉육지진강도증강.
There are a series of NW-trending faults along the Taiwan Strait. Studies show that a series of transverse structures with strike-slip movements could be divided into three types according to the crustal movement, region deformation and fracture characteristic. The three types are the Bashi, Taizhong-Jingjiang and Ningde-Sandiaojiao fault zones respectively. The middle Taizhong-Jingjiang faulted zone is an important boundary which controls the different crustal movements between the north and the south. The whole crusts in the north ( northern coastal Southeast China and northern Taiwan) move eastward, which is the same direction as the strike-slip movement of the Ryukyu subduction zone, and forms the same deformation direction. The south of the fault zone is under the compressive deformation environment between the South China Plate and Philippine Sea Plate, whose deformation is more intense than that of the north. The strengthening trend of seismicity in coastal Southeast China and the situation of stronger seismicity in the south than in the north are related to the stress field and strike-slip: ( 1 ) The stress field changes greater in the south fracture than in the north fracture, multi-fields couple complicatedly and the coupled degree decreases, leading to the asymmetric distribution of creep deformation and stresses locking, therefore , these contribute to the occurrence of earthquakes. (2) Crust uniformity in the east of Fujian is worse than the Taiwan Strait, geophysical field changes obviously, and the components of multi-fields coupling and multi-factors coupling fields are more complicated. Thus, the stability of coupling fields is not high, and it is easily disturbed by the transverse structural strike-slip to produce elastic deformations which contribute to the increase of seismicity.