地质力学学报2026，Vol.32Issue(4)：933-941,9.DOI:10.12090/j.issn.1006-6616.2026005
湖相沉积地震成因负载与球-枕构造的数值模拟研究
Numerical simulation analysis of seismically triggered load and ball-and-pillow structures in the lacustrine sediment
摘要
Abstract
[Objective]Seismically triggered soft-sediment deformation structures(SSDSs)in the lacustrine sediments serve as reliable stratigraphic records for studying paleoearthquake events in tectonically active regions.Load and ball-and-pillow structures,as common types of SSDSs,are generally attributed to gravitational instability caused by an inverse density gradient between adjacent sedimentary layers.However,their formation mechanisms and the quantitative relationship between their development and seismic intensity remain poorly constrained.[Methods]This study employs the multiphase-flow numerical simulation approach implemented in ANSYS Fluent to simulate the formation of load and ball-and-pillow structures in saturated sand-clay layers under different peak ground accelerations(PGAs;0.125g,0.25g,0.5g,and 0.8g)and varying physical properties,including density,dynamic viscosity and layer thicknesses).The effects of sediment physical properties on the development of these deformation structures and their relationship with seismic intensity were investigated.[Results]The results show that as the PGA increases,load and flame structures develop earlier at the sand-clay interface and progressively evolve from small load structures into larger-scale load and ball-and-pillow structures.Under the same PGA,a larger density contrast,a smaller dynamic viscosity contrast,and a thicker overlying sand layer result in greater deformation and larger-scale development of load and ball-and-pillow structures.[Conclusions]The morphologies of the load and ball-and-pillow structures produced by the numerical simulations are highly consistent with those observed in lacustrine sediments in the Tashkorgan area.This agreement supports the proposed mechanical mechanism of their formation and provides a quantitative basis for understanding the development of SSDSs under different seismic and sedimentary conditions.[Significance]This finding verifies the seismic trigger of SSDSs in this region and provides a new technological insight into the study of SSDSs and paleoearthquakes.关键词
湖相沉积/古地震/软沉积变形/负载构造/球-枕构造/数值模拟Key words
lacustrine sediments/paleoearthquake/soft sediment deformation/load structure/ball-and-pillow structure/numerical simulation分类
天文与地球科学引用本文复制引用
严泽龙,范瑞祥,梁莲姬,钟宁,张俊杰..湖相沉积地震成因负载与球-枕构造的数值模拟研究[J].地质力学学报,2026,32(4):933-941,9.基金项目
国家自然科学基金项目(42572128) （42572128）
自然资源部大陆动力学重点实验室开放基金项目(J2408) This research was financially supported by the National Natural Science Foundation of China(Grant No.42572128)and the Open Fund of the Key Laboratory of Continental Dynamics of Ministry of Natural Resources(Grant No.J2408). （J2408）
