华南地质2026，Vol.42Issue(4)：588-601,14.DOI:10.3969/j.issn.2097-0013.2026.04.003
上覆地层厚度对小位移走滑断裂分段性影响的有限元数值模拟
Finite Element Numerical Simulation of the Influence of Overburden Thickness on the Segmentation of Small-displacement Strike-slip Faults
摘要
Abstract
[Objective]Strike-slip faults in the Tarim Basin are generally characterized by small displacement,limited fault throw,and great burial depth.These features result in indistinct offset of seismic reflection events,which restricts their fine identification and structural analysis.Previous studies have preliminarily revealed that the thickness of overlying strata exerts a key control on the segmented behavior of strike-slip faults.However,the quantitative relationships between this factor and parameters such as fault segment length and segment number,as well as the corresponding mechanical governing mechanism,remain to be further explored.[Methods]This study aims to preliminarily reveal the linear correlation trend between stratigraphic thickness and the segment length of small-displacement strike-slip faults using numerical simulation.To investigate the control of overlying stratigraphic thickness on the segmentation pattern of strike-slip faults in the Shunbei area of the Tarim Basin,four groups of finite element models with different overlying stratigraphic thicknesses(2 km,3 km,4 km,and 5 km)were constructed.[Results]The variation laws of fault number,segment length,and strain distribution with stratigraphic thickness were systematically analyzed.Simulation results show that overlying stratigraphic thickness exerts a controlling effect on the segmentation of strike-slip faults.As the stratigraphic thickness increases from 2 km to 5 km,the number of fault zones decreases from 6 to 2,and the average segment length increases from 2.4 km to 12.5 km,showing a linear negative correlation and a linear positive correlation with stratigraphic thickness,respectively.In thin strata,faults are characterized by short segments and multiple branches with dispersed strain.In thick strata,strain energy is concentrated and released,forming long and continuous major faults.[Conclusions]This study confirms that overlying stratigraphic thickness is a key geological factor controlling the segment length of strike-slip faults,and establishes a thickness-segment length model.This model mechanically explains the vertically differential development of strike-slip faults in the Tarim Basin,indicating that thick strata are more conducive to the formation of fault systems with long segments and high connectivity.The research results provide an experimental basis for the identification and prediction of small-displacement strike-slip faults in cratonic basins.关键词
走滑断裂/有限元方法/断层分段长度/塔里木盆地Key words
Tarim Basin/strike-slip fault/finite element method/fault segment length分类
天文与地球科学引用本文复制引用
池禹,张新松,朱素芹..上覆地层厚度对小位移走滑断裂分段性影响的有限元数值模拟[J].华南地质,2026,42(4):588-601,14.基金项目
江西省自然科学基金项目(20232BAB213086) （20232BAB213086）
