Dr. Flores served as a Research Scientist in the Energy Resources Center of the U.S. Geological Survey from 1975–2010; Professor and Chair of the Department of Geology at Sul Ross State University, Alpine, Texas 1966–1975; adjunct faculty at several U.S. universities and external PhD examiner for the Université de Liège, University of the Witwatersrand, and University of Natal from 1982–2010; and consulting geologist/advisor to Anadarko CBM Group in Denver, CO, USA, AECOM/BLM CBM hydrostratigraphy-groundwater modelling for Powder River Basin in Fort Collins, CO, USA, Shanxi Lanyan Coalbed Methane Group and Biogenic Gas Laboratory in Jincheng, China. Since 1995 Dr. Flores has served as an Editorial Board Member of International Journal of Coal Geology, edited international special publications, and organized U.S.-international conferences. Dr. Flores has authored/co-authored publications in coal geology, peat-coal depositional environments, sedimentology, stratigraphy, hydrostratigraphy, basin analysis, coal and coalbed gas resources assessment, coalmine methane, and biogenic coalbed gas of the U.S. and other countries. Dr. Flores is the principal author of the Coal and Coalbed Gas: Fueling the Future, 2014, First Edition and forthcoming Chinese (translation) version.

Dr. Flores is a recipient of several national and international awards: U.S. Department of Interior Distinguished Service Award, U.S. Geological Survey Meritorious Service Award, , Geological Society of America Gilbert H. Cady Award in Coal Geology, University of the Philippines Alumni Award in Geology, Philippines La Union Province Pammadayaw Award, and University of Canterbury Angus Erskine Fellow Award.