中国科学院大学学报2024，Vol.41Issue(1)：1-10,10.DOI:10.7523/j.ucas.2022.059
三维黏弹性模型在月球冷却产生的热应力计算中的应用
Calculating the thermal stress of the moon in cooling process with 3-D viscoelastic model
摘要
Abstract
Thermal stress of the moon due to cooling process is non-negligible in lunar evolution.We calculate the accumulation of thermal stress with 3-D viscoelastic model,and explore the influence of viscosity parameters on thermal stress through comparative experiments.Numerical results suggest that the thermal stress of lithosphere is utterly distinct from deep mantle.The lithosphere is under tangential compression that concentrates at the bottom of the crust because of unevenly distributed cooling rate and elastic strength;on the other hand,the accumulation and relaxation of thermal stress in deep mantle is balanced due to low viscosity,and the thermal stress is in a"hydrostatic"state,which is mainly controlled by the elastic surface.Under the assumption that viscosity of lunar lithosphere is greater than 1028 Pa·s,the tangential compressive stress in lithosphere accumulates to several hundreds of MPa in the present day,while the tensile stress in deep mantle reaches up to 100 MPa.Consequently,part of the shallow moonquake events can be explained by thermal stress.However,the focal mechanism of deep moonquakes is still unclear.We speculate that the tensile thermal stress in deep mantle helps to develop pore structures,and the melting layer provides pore fluid with high pressure,which reduces the fracture strength of mantle medium.关键词
黏弹性介质/有限元法/热应力/月震Key words
viscoelastic medium/finite element method/thermal stress/moonquake分类
天文与地球科学引用本文复制引用
金一民,陶莎,石耀霖..三维黏弹性模型在月球冷却产生的热应力计算中的应用[J].中国科学院大学学报,2024,41(1):1-10,10.基金项目
国家自然科学基金(41774106)资助 （41774106）
