Kinematics and Dynamics of Continental Deformation and the Effective Viscosity of Continental Lithosphere

9527024莫尔纳大陆变形的动力过程和由此产生的大规模运动学之间的关键纽带是应力与应变率之间的本构关系。PI建议确定这种本构关系在变形大陆区域的横向变化，在这些区域中，连续变形近似大陆构造的运动学。计算的速度场将产生内部一致的应变率场，PI将用于确定变形大陆岩石圈的横向变化、垂直平均的有效粘度。这项研究将检验粘性薄片作为大尺度大陆动力学模型的有效性和局限性。有效粘度的量化将揭示低应变率区域是因为高强度还是因为低应力而缓慢变形。有效粘度随着应变率的增加而减小，将可以推断断层上的摩擦和深部韧性变形在抵抗变形方面的相对重要性。此外，运动学本身的研究将解决亚洲构造的具体难题。

9527024 Molnar The key link between dynamic processes and the resulting large-scale kinematics of continental deformation is the constitutive law relating stress to strain rate. The PI proposes to determine lateral variations in such constitutive relationships across deforming continental regions where continuous deformation approximates the kinematics of continental tectonics. Calculated velocity fields will yield an internally consistent strain-rate field that the PI will use to determine the laterally varying, vertically averaged, effective viscosity of deforming continental lithosphere. This study will test the validity and limitation of the thin viscous sheet as a model for large-scale continental dynamics. Quantifying effective viscosity will reveal whether regions of low strain rate deform slowly because of high strength or because of low stress. A decrease in effective viscosity with increasing strain-rate will allow inferences of the relative importance of friction on faults and ductile deformation at depth in resisting deformation. In addition, the study of kinematics alone will address specific conundra of Asian tectonics.