Metamorphic Gradients and Fluid Flow Associated with Crystalline Overthrusts

了解逆冲断层的热和流体流动结果对于理解地壳中的热量和质量传递过程是必要的。许多逆冲断层在其下盘岩石中保留了倒变质梯度，但其形成机制尚不清楚。本研究将对美国亚利桑那州西部两个山脉下盘上地壳岩石的变质作用和流体流动机制进行研究。同时也验证了上盘结晶岩在前向变质过程中释放的流体向上运移导致其发生逆行变质的假说。该方法将是对结构、岩石学、稳定同位素、流体包裹体和40Ar/39Ar系统的综合研究。这些结果将约束产生反向变质梯度的机制，并将增加对与构造事件相关的热量和质量传递过程的理解。

Understanding the thermal and fluid flow consequences of thrust faulting is necessary to understanding heat and mass transfer processes in the earth's crust. Many thrust faults preserve an inverted metamorphic gradient in their footwall rocks, but the mechanisms to produce this are poorly understood. This study will constrain the mechanisms of metamorphism and fluid flow associated with prograde inverted metamorphic gradients in supracrustal rocks of the footwall in two ranges in western Arizona. It will also test the hypothesis that fluids released during the prograde metamorphism migrated upwards and caused retrograde metamorphism in the crystalline rocks of the hanging wall. The approach will be an integrated study of structures, petrology, stable isotopes, fluid inclusions and 40Ar/39Ar systematics. The results will constrain the mechanisms that produce inverted metamorphic gradients, and will increase the understanding of heat and mass transfer processes associated with tectonic events.