1. División de Geociencias Aplicadas, IPICYT, San Luis Potosí, Mexico
2. Department of Geological and Atmospheric Sciences, Iowa State University, Ames, IA, USA
3. Department of Geology, College of William and Mary, Williamsburg, VA, USA
4. Department of Geoscience, The University of Wisconsin, Madison, WI, USA
5. Department of Earth Sciences, Syracuse University, Syracuse, NY, USA