1. Department of Civil and Environmental
Engineering, 121 Hudson Hall, Box 90287, Duke University, Durham, North Carolina 27708, United States
2. Department of Geology, 208 Natural
History Building, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
3. Division of Earth and Ocean
Sciences, Nicholas School of the Environment, 205 Old Chemistry Building,
Box 90227, Duke University, Durham, North
Carolina 27708, United States