1. Department of Geological Sciences, University of Delaware, 101C Penny HallNewark, DE, 19716USA
2. Department of Geography, University of Delaware, 101C Penny HallNewark, DE, 19716USA
3. College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, 104 Wilkinson HallCorvallis, OR, 97331USA
4. Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, TN, USA