Recent research in the southwestern United States has indicated that the so-called "metamorphic Core Complexes" are features resulting from major continental extension. The geologic evidence for very low-angle, regionally extensive detachment faulting is in fundamental conflict with theoretical response of material to extension. All well-studied examples of metamorphic core complexes are located in the southwestern United States. This project will investigate a possible core complex in North China that bears a striking similarity to the US examples. The field work will be done in conjunction with scientists at Peking Universities who are supported by NSF China. Results will provide data to establish whether or not the Hefangkou area is an extensional complex, and if so, will not only help to resolve the existence of Cordilleran-type core complexes outside North America but may provide insights into the essential conditions required for low-angle faulting to occur during continental extension.
