Prograde metamorphic reactions in the lower and middle crust cause extensive and pervasive release of metamorphic fluid leaving comparatively “dry” rocks. The liberated metamorphic fluid is mobile and buoyant with respect to the surrounding rock mass and thus migrates upwards towards the Earth’s surface (Walther and Wood, 1986). Retrograde metamorphic reactions in the middle and upper crust consume some of this mobile fluid. But fluid flow in the middle and upper crust is channeled and uptake of these fluids by retrograde metamorphic reactions is thus spatially limited to deformation zones (fold hinges, shear zones, faults: Graham et al., 1997). The remaining fluid enters surface reservoirs and can thus influence global climate. The aim of this project is to quantify metamorphic fluid release in the lower and middle crust with metamorphic fluid uptake in the middle and upper crust so as to provide a basis for calculating the metamorphic contribution of water and carbon to Earth’s surface. The project will focus on the Hercynian and Caledonian mountain building events and will provide a basis for assessing their potential impact on long term climate variability. This study is important because of controversy regarding whether mountain building should be viewed as a net source or sink of atmospheric CO2 (Skelton, 2011). Classic areas where metamorphic fluid flow has been studied and where crustal sections are exposed will be used in this study. These are in France, New England and Scotland.
-Applicants must have completed a research degree (e.g. Masters) or university study of 240 hp (4 years), with at least 60 hp (1 year) at the advanced (research) level. -At least 90 hp in Geology or Earth Science and at least 30 hp Math/Physics/Chemistry and/or Biology, depending on the research topic in Geology. -At least 60 hp at the advanced level, including an independent project in Geology or Earth Sciences. For some PhD topics in Geology, students with degrees in appropriate Natural Science topics such as Physics, Chemistry, Math or Biology may be admitted.