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Gretchen Hoffman

Photo of G.Hoffman
Emeritus — Principal Sr. Coal Geologist
New Mexico Bureau of Mines & Mineral Resources
New Mexico Tech
801 Leroy Place
Socorro NM 87801-4796
Phone: (575) 835-6105
Fax: (575) 835-6333


  • Adams State College, Alamosa, CO 1972-1976 - B.A. -- One of the coldest places in the US, known as the Land of the Cool Sunshine. ASU is a terrific small college. I took geology as a science credit at ASC and ended up majoring in geology and archeology.
  • University of Arizona, Tucson, AZ 1976-1979 - M.S.--One of the hottest places in the US--The U of A was a real culture shock for me coming from Adams State, a school of about 2000 students, to a campus of over 60,000 students. I was lucky enough to get an assistantship, have a great thesis committee and an interesting thesis area looking at an early Cretaceous rudist patch reef near Bisbee, AZ.

Professional Experience

    Gretchen has worked at the New Mexico Bureau of Mines for 34 years as a coal geologist. During this time, she has done field mapping in west-central New Mexico, ran a drilling program for a 3-year coal quality evaluation study in the San Juan Basin, and done numerous coal resource evaluation studies primarily in the San Juan Basin. Developing coal databases has been a integral part of her work at the Bureau. For the past 28 years Gretchen has worked on US Geological Survey cooperative grants evaluating and entering data into the National Coal Resource Data System. From 1998 to 2005, Gretchen was the principal investigator for four Coal Availability studies, funded by the US Geological Survey, evaluating coal resources using GIS. Three of the availability studies were on areas within the San Juan Basin, and the final study (2005) was centered in the Raton basin. Prior to this availability study, Gretchen worked on a project with other researchers at NM Tech looking at the coalbed methane potential in the Raton basin.

    Other interests include looking at industrial minerals associated with coal, such as humates, clinker and fly ash. Gretchen's interest in fly ash has led to other research on use of natural and artificial pozzolans and supplementary cementitious materials in cement and concrete. Gretchen has also collaborated with Maureen Wilks on the Mine Map initiative, particularly in collecting historic coal mine maps. As part of this initiative mine maps in the San Juan basin have been geo-referenced and linked to an Arcmap project with associated mine locations with geologic and production data (Open-file report 549).

    As part of the Bureau's outreach program, Gretchen has written articles on coal geology and mining for Lite Geology and has taught topographic map reading to teachers at several Rockin' Around New Mexico

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    Gretchen Explaining waypoints at golf GPS exercise-Rockin 2006

Current Projects

  • Data entry and verification of coal data into the US Geological Survey’s National Coal Resource Data System
  • Assist with the development and transition of well and aquifer mapping databases to a relational database management system that will have Web and GIS functionality.
  • Geo-reference and verify data for abandoned coal mines in the for the Raton Basin. This is a continuation of the work done in the San Juan Basin. (Open-file reportĀ  549)
  • Manage Bureau’s Perlite testing lab
  • Manage Bureau’s Coal Data Library

Areas of Interest

  • Coal quality and coal resources of New Mexico
  • Compiling historical data and maps for abandoned coal mines in the State
  • Application of databases and GIS to resource evaluations.

Recent Publications, Published Abstracts (see full publication list)

  1. Hoffman, Gretchen K.; Wilks, Maureen, 2013, Acquiring and georeferencing coal mine maps: San Juan Basin, NM, in: 2013 New Mexico Geological Society,Spring Meeting, April 12, 2013, Macey Center, New Mexico Tech, Socorro, NM, New Mexico Geology, v. 35, no. 2, pp. 51.
  2. Hoffman, G.K., March 2009, Factors Influencing use of Mineral Admixtures for the past decade in the Western US, SME Annual Meeting, Denver, CO, preprint 09-081.
  3. Harben, P., Austin, G., Hoffman, G., McLemore, V., Caledon, M., and Barker, J., May 2007, Industrial minerals, a staple in the economy of the Land of Enchantment: Proceedings of the 43rd Forum on the Geology of Industrial Minerals 2007.
  4. Hoffman, G., May 2007, Environmental and economic factors influencing use of mineral admixtures in concrete over the last 25 years: Proceedings of the 43rd Forum on the Geology of Industrial Minerals 2007, Colorado Geological Survey, Resource Series 46 p. 301-322. .-- Abstract
  5. Hoffman, G.K., 2006, Pozzolans and Supplementary Cementitious Materials: in Kogel, JE. Trivedi, NC., Barker,J.M., and Krukowski, S.T., eds., .Industrial Minerals and Rocks 7th Edition, Society for Mining, Metallurgy and Exploration, Inc., Littleton, CO,  p. 1161-1172
  6. Hoffman, G.K., and Austin, G.S., 2006, Soil Amendments: in Kogel, JE. Trivedi, NC., Barker, J.M., and Krukowski, S.T., eds., .Industrial Minerals and Rocks 7th Edition, Society for Mining, Metallurgy and Exploration, Inc., Littleton, CO,  p. 1477-1485.
  7. Hoffman, G.K., and Jones, G.E., 2005, Availability of coal resources in the Vermejo and Raton formations, Raton coalfield, Raton Basin, northeast New Mexico, New Mexico Bureau of Geology and Mineral Resources Open-file report 490, 48 p., 2 appendices.
  8. Brian S. Brister, Gretchen Hoffman and Thomas W. Engler, 2005, Oil and gas resource development Eastern Valle Vidal Unit: A 20 year Reasonable Foreseeable Development Scenario (RFDS) Carson National Forest, New Mexico Bureau of Geology and Mineral Resources Open-file report 491, 81 p. 2 appendices, GIS project, database.
  9. Hoffman, G.K., and Brister, B.S., November, 2004, History Of Development Of Coal And Coalbed Methane Resources Of The Raton Coalfield In New Mexico: Geological Society of America Annual Mtg.
  10. Hoffman, G. K., and Brister, B. S., 2003, New Mexico’s Raton Basin coalbed methane play; New Mexico Geology, vol.25, no. 4,  p. 95-110.

Coal Related Links

Coal Companies Operating Mines in New Mexico

There are now (2014) 4 operating coal mines in New Mexico. Two are owned by BHP Billiton and two by Peabody Energy. Recently (December, 30, 2013) the Navajo Mine operated by BHP Billiton was sold to the Navajo Transitional Energy Company, owned by the Navajo Nation.

Coal and Energy links on the web

Power Plants in New Mexico