Collaborative Research: The Southern Sierra Nevada Continental Dynamics Project

该项目涉及沿内华达山脉和横跨内华达山脉的多学科(地震、大地电磁)断面，以研究这些山脉下的地壳和上地幔。主要调查人员确定了内华达山脉隆升的原因及其与毗邻的死亡谷伸展省和南部圣华金盆地的关系。目前，已经提出了两种端元模型来描述该范围的抬升。它们是：(A)深部地壳根部的均衡补偿和(B)与向东伸展有关的软流圈上涌。这两种模式对大陆的动力学行为有着根本不同的后果，特别是在地壳部分要么被来自上地幔的物质浸没，要么(B)被削弱和挤压以填充伸展空洞的方式。除了世界范围内可比山脉的抬升和相关延伸之外，西尔兰根问题的解决将更好地理解全球重大特征的例子包括：控制涎岩基底推覆体拆离方式的因素；碰撞带如何在其自身的负担下坍塌；以及陆内断裂如何将分割应变转换到莫霍面及其以外。

This project involves multidisciplinary (seismic, magnetotelluric) transects along and across the Sierra Nevada in order to examine the crust and upper mantle beneath these mountains. The principal investigators resolve the cause of uplift of the Sierra Nevada and its relation to the adjoining Death Valley extensional province and the southern San Joaquin basin. Currently, two end-member models for uplift of the range have been presented. These are: (a) isostatic compensation of a deep crustal root and (b) upwelling of the asthenosphere associated with extension to the east. These two models have fundamentally different consequences for the dynamic behavior of the continents, particularly in the manner in which crustal sections are either (a) underplated by materials from the upper mantle or (b) weakened and extruded to fill in extensional voids. In addition to the uplift and related extension of comparable mountain ranges worldwide, examples of globally significant features that will be better understood by resolution of the Sierran root question include: factors controlling the manner in which sialic basement nappes detach; how collision zones collapse under their own burden; and how intracontinental transform faults partition strain to and beyond the Moho.