COLLABORATIVE RESEARCH: Mechanics of Footwall Uplift DuringDetachment Faulting

浅倾滑脱断层下方剥蚀的下盘岩石的均衡抬升被认为是造成滑脱的向上拱起，并可能导致断层的浅部过去被遗弃。这一理论预测，随着断层滑动的继续，断层陡峭、活动和浅不活动部分之间的铰接区将通过下盘迁移。另一种模型预测，不同的应变路径将记录在下盘岩石中。这项研究将通过检查来自不同构造环境的三条拆离断层下围岩的应变状态来验证迁移铰链区的假设：犹他州的比弗坝山脉、加利福尼亚州的惠普尔山脉和东部阿尔卑斯山的布伦纳线。这一结果将允许对运移铰模型进行评估，并将对各种构造环境中的伸展带具有广泛的适用性。

Isostatic uplift of denuded footwall rocks beneath a shallowly-dipping detachment fault is thought to cause upwards arching of the detachment and may cause the shallow past of the fault to be abandoned. This theory predicts that as fault slip continues, the hinge zone between steep, active and shallow, inactive parts of the fault will migrate through the footwall. Alternative models predict different strain paths will be recorded in the footwall rocks. This study will test the hypothesis of a migrating hinge zone by examining the strain state in footwall rocks beneath three detachment faults from different tectonic settings: Beaver Dam Mountains, Utah; Whipple Mountains, California; and Brenner Line, eastern Alps. The results will allow assessment of the migrating hinge models and will have broad applicability to extensional zones in a variety of tectonic environments.