scholarly article by Michael L. Zientek et al published 2014 in Scientific Investigations Report

scientific article published in 2000

scientific article published in 2008

article

scientific article published in 2000

scientific article published in 2000

scientific article published in 2003

article published in 2002

scientific article published in 2003

scientific article published in 2001

scientific article published in 2001

scientific article published in 1997

scientific article published in 1997

scientific article published in 1997

scholarly article

scholarly article by Robert E. Powell published in January 2015

article

article by Fred K. Miller & Pamela M. Cossette published 2004 in Open-File Report

scholarly article in Scientific Investigations Report, 2012

scholarly article in Scientific Investigations Report, 2014

article by Douglas M. Morton et al published January 2014 in Memoir / Geological Society of America