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Published Papers:
Open File Reports:
Talks, with Published Abstracts:
(Previous married name Gretchen Hoffman Roybal)
Roybal, G.H., and Eveleth, R.W., 1982, Overview of surface mining in New Mexico and ongoing reclamation projects; in Reclamation of mined lands of the Southwest, a Symposium for the Soil Conservation Society of America.
Eveleth, R.W., Bieberman, R.A., Campbell, F.W., and Roybal, G.H., 1982, Mineral and mineral-fuel production activities in New Mexico during 1980; in New Mexico Bureau of Geology and Mineral Resources Annual Report, 1981-1982, p. 56-64.
Roybal, G.H., 1983, Coal geology studies by New Mexico Bureau of Geology and Mineral Resources: New Mexico Bureau of Geology and Mineral Resources Annual Report, July 1, 1981 - June 30, 1982.
Roybal, G.H., and Eveleth, R.W., 1983, Reclamation of surface mining areas in New Mexico: New Mexico Bureau of Geology and Mineral Resources Annual Report, July 1, 1981 - June 30, 1982.
Eveleth, R.W., Bieberman, R.A., McLemore, V.T., and Roybal, G.H., 1984, Mineral and mineral-fuel production in New Mexico, 1983; in New Mexico Bureau of Geology and Mineral Resources Annual Report, 1982-1983, p. 34.
Kottlowski, F.E., Campbell, F.W., Roybal, G.H., and Hatton, K.S., 1985, New Mexico in Keystone Coal Industry Manual: McGraw-Hill, Inc. p. 531-540.
Roybal, G.H., Campbell, F.W., Beaumont, E.C., Cohen, A.D., Kuellmer, F.J., Kottlowski, F.E., 1986, Quality assessment of strippable coals in New Mexico, Year I, Phase II, Fruitland and Cleary coals in the San Juan Basin of Northwestern New Mexico: NMERDI Report No. 2-73-4304.
Kottlowski, F.E., Roybal, G.H., and Hatton, K.S., 1986, Coal seams in New Mexico in Keystone Coal Industry Manual: McGraw-Hill, Inc. p. 514-523.
Roybal, G.H., 1987, Coal mining and production in New Mexico; in Roybal, G.H., Anderson, O.J., and Beaumont, E.C., (compilers), Coal deposits and facies changes along the southwestern western of the Late Cretaceous Seaway, west-central New Mexico: New Mexico Bureau of Geology and Mineral Resources Bulletin 121, p. 35-36.
Roybal, G.H., 1987, Road log for optional side trip to Fence Lake No. 1 mine north of Quemado, New Mexico; in Roybal, G.H., Anderson, O.J., and Beaumont, E.C., (compilers), Coal deposits and facies changes along the southwestern western of the Late Cretaceous Seaway, west-central New Mexico: New Mexico Bureau of Geology and Mineral Resources Bulletin 121, p. 31.
Roybal, G.H., and Barker, J.M., 1987, Geology and production of humate and weathered coal in New Mexico: in Transactions, Society of Mining and Engineers of AIME, Vol. 280, p. 2105-2110.
Roybal, G.H., Campbell, F.W., Beaumont, E.C., Cohen, A.D., Kuellmer, F.J., Kottlowski, F.E., Cook, K. H., 1987, Quality assessment of strippable coals in New Mexico, Year II, Phase II, Fruitland, Menefee, and Crevasse Canyon Formation coals in the San Juan Basin of Northwestern New Mexico: NMRDI Report No. 2-74-4331.
Roybal, G.H., Hatton, K.S., and Kottlowski, F.E., 1987, New Mexico description of seams in Keystone Coal Industry Manual, McGraw-Hill, p. 479-488.
Anderson, O.J., Chamberlin, R.M., and Roybal G.H., 1987, Road log from Fence Lake, New Mexico, to Springerville, Arizona; in Roybal, G.H., Anderson, O.J., and Beaumont, E.C., (compilers), Coal deposits and facies changes along the southwestern western of the Late Cretaceous Seaway, west-central New Mexico: New Mexico Bureau of Geology and Mineral Resources Bulletin 121, p. 26-30.
Beaumont, E.C., and Roybal, G.H., 1987, Road log from Springerville to Show Low, Arizona; in Roybal, G.H., Anderson, O.J., and Beaumont, E.C., (compilers), Coal deposits and facies changes along the southwestern western of the Late Cretaceous Seaway, west-central New Mexico: New Mexico Bureau of Geology and Mineral Resources Bulletin 121, p. 30.
Campbell, F.W., and Roybal, G.H., 1987, Characterization of New Mexico coals, Menefee and Crevasse Canyon formations; in Roybal, G.H., Anderson, O.J., and Beaumont, E.C., (compilers), Coal deposits and facies changes along the southwestern western of the Late Cretaceous Seaway, west-central New Mexico: New Mexico Bureau of Geology and Mineral Resources Bulletin 121, p. 41-48.
Kottlowski, F.E., Roybal, G.H., and Hatton, K.S., 1988, Coal seams in New Mexico in Keystone Coal Industry Manual: Maclean Hunter Publishing Co., Chicago, Illinois, p. 464-473.
Roybal, G.H., Campbell, F.W., Beaumont, E.C., Bellis, D., Kottlowski, F.E., Cohen, A.D., 1988, Quality assessment of strippable coals in New Mexico, Year III, Phase II, Menefee, Crevasse Canyon and Moreno Hill Formation coals in the San Juan Basin and Salt Lake coal field: NMRDI Report No. 2-76-5310.
Roybal, G.H., 1989, Coal characteristics of major coal-bearing sequences, Gallup field, northwestern New Mexico: in New Mexico Geological Society 40th Guidebook, p. 309-315.
Roybal, G.H., 1989, New Mexico coal resources, activities and outlook; in Energy Frontiers in the Rockies: Am. Assoc. of Petroleum Geologists, Rocky Mountain Section Meeting, Albuquerque, New Mexico, p. 309-315.
Kottlowski, F.E., Campbell, F.W., Roybal, G.H., and Hatton, K.S., 1989, New Mexico description of seams; in Keystone Coal Industry Manual: Maclean Hunter Publishing Co., Chicago, Illinois, p. 534-543.
Hoffman, G.K., 1990, Coal geology and mining history in the Dawson area, southeastern Raton coal field, New Mexico; in New Mexico Geological Society 41st Guidebook, P. 397-403.Abstract
Eveleth, R.W., Bieberman, R.A., Roybal, G.H., and McLemore, V.T., 1990, Mineral and mineral-fuel production activities in Mexico during 1983; in New Mexico Bureau of Geology and Mineral Resources Triennial Report, July 1, 1983 to June 30, 1986, p. 37-43.
Eveleth, R.W., Bieberman, R.A., Roybal, G.H., and McLemore, V.T., 1990, Mineral and mineral-fuel production activities in New Mexico during 1985; in New Mexico Bureau of Geology and Mineral Resources Triennial Report, July 1, 1983 to June 30, 1986, p. 51-58.
Hoffman, G.K., February 1991, Geology and quality of the Menefee Formation coals, Monero coal field, Rio Arriba County, New Mexico; New Mexico Geology, v. 13, no. 1, p.1-8, 21.
Campbell, F.W., Hoffman, G.K., Kottlowski, F.E., and Arkell, B.W., 1991, Geology and coal resources of New Mexico's small coalfields; in Coalfields of New Mexico: Geology and resources, C.L. Molina, D.A. Jobin, J.T. O'Conner, and F.E. Kottlowski eds.: U.S. Geological Survey, Bulletin 1972, p. 69-77.
Kottlowski, F.E., Hoffman, G.K., Anderson, O.J., and Hatton, K.S., 1991, New Mexico description of seams; in Keystone Coal Industry Manual: Maclean Hunter Publishing Co., Chicago, Illinois, p. 114-123.
Hoffman, G.K., 1992, Coal information; in Quadrennial Report for the Fiscal Years July 1, 1986 to June 30, 1990, F.E. Kottlowski and staff: New Mexico Bureau of Geology and Mineral Resources, p. 6-7.
Hoffman, G.K., Beaumont, E.C., and Bellis, D., 1992, Environmental controls related to coal quality variations in the Fruitland Formation, San Juan Basin, New Mexico; in Controls on the distribution and quality of Cretaceous coals, P.J. McCabe, and J.T. Parrish, eds.: Geological Society of America, Special Publication 267, p. 37-55.
Beaumont, E.C., and Hoffman, G.K., 1992, Supplementary road log 1, from intersection of Piedra Lumbre road and NM 197 to Star Lake and Pueblo Alto trading posts; in New Mexico Geological Society, 43rd Guidebook, p. 65-70.
Beaumont, E.C., and Hoffman, G.K., 1992, Interrelationships between the upper coal member of the Menefee Formation, the La Ventana Tongue, and the Lewis Shale in the southeastern San Juan Basin, New Mexico; in New Mexico Geological Society, 43rd Guidebook, p. 207-216.
Eveleth, R.W., Broadhead, R.F., Roybal, G.H., and McLemore, V.T., 1992, Mineral and mineral-fuel production activities in New Mexico during 1987; in Quadrennial Report for the fiscal years July 1, 1986 to June 30, 1990, F.E. Kottlowski and staff: New Mexico Bureau of Geology and Mineral Resources, p. 74-82.
Kottlowski, F.E., Hoffman, G.K., Anderson, O.J., and Hatton, K.S., 1992, New Mexico description of seams; in Keystone Coal Industry Manual: Maclean Hunter Publishing Co., Chicago, Illinois, p. 104-113.
Lucas, S.G., Williamson, T.E, Smith, L.N., Wright-Dunbar, R., Hallett, B., Kues, B.S., Hoffman, G.K., Hunt, A.P., Love, D.W., McLemore, V.T., and Hadley, R.F., 1992, First-day road log, from Cuba to La Ventana, San Luis, Cabezon, Mesa Portales, Mesa de Cuba and return to Cuba; in New Mexico Geological Society, 43rd Guidebook, p. 1-32.
Hoffman, G.K., and Hatton, K.S., 1993, New Mexico description of seams; in Seam Analyses, U.S. and Canada; Keystone Coal Industry Manual: Maclean Hunter Publishing Co., Chicago, Illinois, p. 107-116.
Hoffman, G.K., Campbell, F.W., and Beaumont, E.C., 1993, Quality assessment of strippable coals in northwestern New Mexico: Fruitland, Menefee, and Crevasse Canyon Formation coals in San Juan Basin, and Moreno Hill Formation coals in Salt Lake field: New Mexico Bureau of Geology and Mineral Resources Bulletin 141, 84 p. Abstract
Hoffman, G.K., Fall 1993, Dawson, a town dependent on coal; in Lite Geology: New Mexico Bureau of Geology and Mineral Resources, 4 p.
Hoffman, G.K., 1994, Coal geology of the lower Moreno Hill Formation, Salt Lake field, west-central, NM; in New Mexico Geological Society, 45th Guidebook. p. 283-289. Abstract
Hoffman, G.K., Winter 1994, Have you ever wondered about coal?; in Lite Geology: p. 2-5, 9-10.
Hoffman, G.K., 1994, Demonstrated reserve base for coal in New Mexico, Final Report: Department of Energy- Energy Information Administration Cooperative Agreement DOE-FC0193EI23974, 83 p.
Hoffman, G.K., Austin, G.S., 1994, Agricultural materials: Soil additives, in Industrial Rocks and Minerals, 6th Edition, D.D. Carr, senior ed.: Society for Mining, Metallurgy and Exploration, Inc., p. 89-96.
Hoffman, G.K., and Hatton, K.S., 1994, New Mexico description of seams; in Seam Analyses, U.S. and Canada; Keystone Coal Industry Manual: Maclean Hunter Publishing Co., Chicago, Illinois, p. 107-116.
Hoffman, G.K., Spring 1995, Have you ever wondered about coal mining?; in Lite Geology: p. 2-9.
Hoffman, G.K., Barker, J.M., and Austin, G.S., 1995, Overview of humate production in North America; in Merlini, A.A., Shasta, ed., Proceedings of the 30th Forum on the Geology of Industrial Minerals [1994], New Brunswick Department of Natural Resources and Energy, Minerals and Energy Division, Miscellaneous Report 16, p. 55-70. Abstract
Hoffman, G.K., and Hatton, K.S., 1995, New Mexico description of seams; in Seam Analyses, U.S. and Canada; Keystone Coal Industry Manual: Maclean Hunter Publishing Co., Chicago, Illinois, p. 107-116.
Hoffman, G.K., Verploegh, J., Barker, J.M., 1996, Geology and chemistry of humate deposits in the southern San Juan Basin, New Mexico; in Austin, G.S., et al. (eds.) Proceedings of the 31st Forum on the Geology of Industrial Minerals-Borderland Forum: New Mexico Bureau of Geology and Mineral Resources Bulletin 154, p. 105-112. Abstract
Hoffman, G.K., 1996, Natural clinker: The red dog of aggregates in the Southwest; in Austin, G.S., et al. (eds.) Proceedings of the 31st Forum on the Geology of Industrial Minerals-Borderland Forum: New Mexico Bureau of Geology and Mineral Resources Bulletin 154, p.187-196. Abstract
Newman, T.E., and Hoffman, G.K., 1996, Brucite deposit in Marble Canyon, Culberson County, Texas; in Austin, G.S., et al. (eds.) Proceedings of the 31st Forum on the Geology of Industrial Minerals-Borderland Forum: New Mexico Bureau of Geology and Mineral Resources Bulletin 154, p.37-42.
Austin, G.S., Hoffman, G.K., 1996, Index to Proceeding of the 25th-31st Forum: New Mexico Bureau of Geology and Mineral Resources Circular 204, 20 p.
Hoffman, G.K., 1996, Coal resources of New Mexico: New Mexico Bureau of Geology and Mineral Resources Resource map 20, 22 p. text, 1 sheet, scale 1:1,000,000. Introduction
Austin, G.S., Hoffman, G.K., compilers, 1996, Index to Proceeding of the 25th-31st Forum: New Mexico Bureau of Geology and Mineral Resources Circular 204, 20 p.
Hoffman, G.K., and Hatton, K.S., 1996, Coal geology of New Mexico; in Coal geology and description of U.S. coal fields; Keystone Coal Industry Manual: Intertec Publishing Co., Chicago, Illinois, p. G-112-121.
Hoffman, G.K., and Hatton, K.S., 1997, Coal geology of New Mexico; in Coal geology and description of U.S. coal fields; Keystone Coal Industry Manual: Intertec Publishing Co., Chicago, Illinois, p. 615-623.
Hoffman, G.K., 1997, Coal Mines in the vicinity of Farmington, NM, 1997, in New Mexico Geological Society Guidebook 48, p. 44.
Hoffman, G.K., and Hatchell, W.O., 1998, Coal geology of New Mexico; in Coal geology and description of U.S. coal fields; Keystone Coal Industry Manual: Intertec Publishing Co., Chicago, Illinois, p. 639-648.
Hoffman, G.K., May 2000, Uses of
Fly Ash from New Mexico Coals: New Mexico Geology, Vol. 22, No. 2, p. 25-36.
Abstract
Rohrbacher, T. J., Molnia, C.L., Osmonson,
L.M., Carter, M.D., Ekins, W., Hoffman, G.K., Tabet, D.E., Schultz, J.E., Scott,
D.C., Teeters, D.D., Jones, G.E., Quick, J.C., Hucka, B.P., and Hanson, J.A.,
2000, Coal Availability, Recoverability and Economic Evaluations of Coal Resources
in the Colorado Plateau, Colorado, New Mexico and Utah, in Chapter F
of Geology and Resource Assessment of Coal in the Colorado Plateau: Arizona,
Colorado, New Mexico, and Utah:: U.S. Geological Survey Professional Paper 1625-B,
104 p., 57 figures, and 21 tables, CD-ROM.
Hoffman,
G.K., Jones, G.E., 2001, Coal availability studies: Fruitland and Menefee Formations,
San Juan Basin ,
New Mexico :
in Transactions, Society for Mining, Metallurgy, and Exploration,
Inc., vol. 310.
Brister,
B.B., and Hoffman, G.K., 2002; Fundamental Geology of the San
Juan Basin
Energy Resources, In Brister, B.B.
and Price, L.G., eds. New Mexico 's
Energy, Present and Future-Policy, Production, Economics, and the Environment:
New Mexico Bureau of Geology and Mineral Resources, Decision-Makers field conference
2002, p.21-25.
Hoffman,
G.K., 2002; New Mexico 's
Coal Industry-Resources, Production and Economics; In Brister, B.B. and
Price, L.G., eds. New Mexico 's
Energy, Present and Future-Policy, Production, Economics, and the Environment:
New Mexico Bureau of Geology and Mineral Resources, Decision-Makers field conference
2002, p.65-70.
Hoffman,
G.K., 2002; The Uses of Fly Ash in New Mexico
; In Brister, B.B. and Price, L.G.,
eds. New Mexico 's
Energy, Present and Future-Policy, Production, Economics, and the Environment:
New Mexico Bureau of Geology and Mineral Resources, Decision-Makers field conference
2002, p.85-88.
Hoffman, G.K., 2002, Fly ash utilization in the Western
United States : In Scott, P.W.,
and Bristow, C.M., eds., Industrial Minerals and Extractive Industry Geology:
The Geological Society , London ,
p. 331-339.
Roybal, G.H., 1982, Geology and coal resources of Tejana Mesa quadrangle, Catron County, New Mexico: New Mexico Bureau of Geology and Mineral Resources Open File Report 178.
Chamberlin, R.M., Logsdon, M.J., Eveleth, R.W., Bieberman, R.A., Roybal, G.H., Osburn, J.C., North, R.M., McLemore, V.T., and Weber, R.H., Preliminary evaluation of the mineral resource potential of the Sierra Ladrones Wilderness Study area, Socorro County, New Mexico: New Mexico Bureau of Geology and Mineral Resources Open-file Report 179, 193 p.
Campbell, F.W., Roybal, G.H., 1984, Geology and coal resources of the Fence Lake 1:50,000 quadrangle, Catron and Cibola Counties, New Mexico: New Mexico Bureau of Geology and Mineral Resources Open File Report 207.
McLemore, V.T., Roybal, G.H., Broadhead, R.F., Chamberlin, R.M., North, R.M., Osburn, J.C., Arkell, B.W., Colpitts, R.M., Bowie, M.R., Anderson, K., Barker, J.M., and Campbell, F.W., 1984, Preliminary report on the geology and mineral resource potential of northern Rio Puerco resource area in Sandoval and Bernalillo Counties and adjacent parts of McKinley, Cibola, and Santa Fe Counties: New Mexico Bureau of Geology and Mineral Resources Open File Report 211.
McLemore, V.T., Broadhead, R.F., Roybal, G.H., Chenowith, W.L., Barker, J.M., North, R.M., Bowie, M.R., Hingtgen, J.S., Murray, D., Klein, K., Brown, K.B., and Austin, G.S., 1986, A preliminary mineral-resource potential of Cibola County, Northwestern New Mexico: New Mexico Bureau of Geology and Mineral Resources Open File Report 230.
McLemore, V.T., Roybal, G.H., Birdsall, K., Broadhead, R.F., Chenowith, W.L., North, R.M., Barker, J.M., Copeland, P., Bowie, M.R., Hingtgen, J.S., Brown, K.B., Klein, K., 1986, A preliminary mineral resource potential of McKinley County, Northwestern New Mexico: New Mexico Bureau of Geology and Mineral Resources Open File Report 231.
McLemore, V.T., Broadhead, R.F., Cook, K., Chenowith W.L., Barker, J.M., Roybal, G.H., North, R.M., Copeland, P., Bowie, M.R., Hingten, J.S., Klein, E., and Brown, K.B., 1986, A preliminary mineral-resource potential of San Juan County, northwestern New Mexico: New Mexico Bureau of Geology and Mineral Resources Open File Report 232.
Hoffman, G.K., 1990, Coal-bearing formations and available coal data in the western San Juan Basin, on the Chaco Canyon, Chacra Mesa, Farmington, Gallup, Grants, Toadlena, and Zuni 1:100,000 quadrangles: New Mexico Bureau of Geology and Mineral Resources Open-file Report 363, 57 p.
Hoffman, G.K., August 1990, Coal-bearing formations and available coal data in the eastern and southern San Juan Basin on the Navajo Reservoir, Chama, Abiquiu, Los Alamos, Albuquerque, Acoma Pueblo and Fence Lake 1:100,000 quadrangles: New Mexico Bureau of Geology and Mineral Resources Open-file Report 369, 22 p., 14 sheets.
Hoffman, G.K., 1991, Quality assessment of strippable coals in northwest New Mexico: Drilling data, chemical and petrographic analyses for the Fruitland, Menefee, Crevasse Canyon, and Moreno Hill formations: New Mexico Bureau of Geology and Mineral Resources Open-file Report 373A-AA, 1,614 p.
Hoffman, G.K., 1996, Influence of depositional environment on clay mineralogy in the coal-bearing lower Moreno Hill Formation, Salt Lake coal field, west-central New Mexico: New Mexico Bureau of Geology and Mineral Resources Open-file report 427, 21 p.
Hoffman, G.K. 1996, Demonstrated reserve base for coal in New Mexico, modified from final report for cooperative agreement DOE-FC0193EI23974: New Mexico Bureau of Geology and Mineral Resources Open-file report 428, 89 p., 2 appendices. Abstract
Hoffman, G.K., and Jones, G.E.,
1998, Availability of coal resources in the Fruitland Formation, San Juan
Basin, northwest New Mexico: New Mexico Bureau of Geology and Mineral Resources
Open-file report 438, 15 p. Introduction
Hoffman,
G.K., and Jones, G.E., 2001, Coal Availability Study-Upper Menefee Formation
in the Chacra Mesa, La Ventana fields, Northwest New Mexico: New Mexico Bureau
of Mines and Mineral Resources Open-file report 457, 16 p., 1 appendix.
Hoffman, G.K., and Jones, G.E.,
2001, Coal Availability Study-Fruitland Formation in the Fruitland and Navajo
fields, Northwest New Mexico : New Mexico Bureau of Geology and Mineral Resources
Open-file report 464, 33 p., 1 appendix.
Broadhead, R.F., and Hoffman, G.K., 2002, Oil, Natural Gas and Coal Potential
of McKinley County, New Mexico: New Mexico Bureau of Geology and Mineral Resources
Open-file report 470, 46 p., ArcView© project.
Roybal, G.H., and Barker, J.M., October 1985, Geology and production of humate and weathered coal in New Mexico, SME-AIME Fall Meeting, Albuquerque, New Mexico - Abstract and preprint no. 85-408.
Roybal, G.H., and Campbell, F.W., April 1986, Quality assessment of strippable coals in New Mexico, New Mexico Geological Society Spring Meeting, Socorro, New Mexico, Abs. with Programs; New Mexico Geology, v. 8, no. 3, p. 67.
Roybal, G.H., September 1986, Characterization of New Mexico coals, Abs. American Assoc. of Petroleum Geologists, Rocky Mountain Section Meeting, Casper, Wyoming, vol. 70, no. 8, p. 1053.
Roybal, G.H., and Beaumont, E.C., November 1988, Coal quality variations in the Fruitland Formation, New Mexico (abs.): Geological Society of America, national meeting, Abstract with Programs, vol. 20 no 7, p. A89.
Beaumont, E.C., and Roybal, G.H., October 1989, Potential for economic coal development in the upper coal member of the Menefee Formation, Torreon wash area, Sandoval County, New Mexico: Abs., American Assoc. of Petroleum Geologists, Rocky Mountain Section Meeting, Albuquerque, New Mexico, vol. 73 no 9, p. 1147.
Hoffman, G.K., April 1990, Recent investigation of the Menefee coals, Monero coal field, Rio Arriba County, New Mexico (abs.): New Mexico Geological Society Spring Meeting, Socorro, New Mexico.
Hoffman, G.K., April 1992, Coal characteristics of the upper and Cleary Coal Members of the Cretaceous Menefee Formation in the La Ventana-Chacra Mesa Fields, southeastern San Juan Basin (abs.): New Mexico Geological Society Spring Meeting, Socorro, New Mexico, New Mexico Geology v. 14, p. 64-65.
Hoffman, G.K., February 1993, Coal quality characteristics of the Fruitland and Menefee Formations in the San Juan Basin, northwest New Mexico: Four Corners Geological Society Meeting, Durango Colorado, Four Corners Geological Society newsletter.
Hoffman, G.K., April 1993, Coal quality trends of the Fruitland and Menefee Formations in the San Juan Basin, Northwest New Mexico: (Abs) New Mexico Geological Society Spring Meeting, Socorro, New Mexico, proceedings volume, p. 30.
Hoffman, G.K., Verploegh, J., Barker, J.M., February 1994, Geology and chemistry of humate deposits in the southern San Juan Basin, New Mexico: (ABS) SME Annual Meeting and Exhibit Pocket Program, Albuquerque, New Mexico, p. 104, pre-print 94-102, 10 p.
Hoffman, G.K., Barker, J.M., and Austin, G.S., May 1994, Overview of humate production in North America: in proceedings, 30th Forum on the Geology of Industrial Minerals, Halifax, Nova Scotia.
Hoffman, G.K., April 1995, Natural Clinker- The red dog of aggregates in the Southwest: in proceedings 31st Forum on the Geology of Industrial Minerals, El Paso, Texas.
Hoffman, G.K., April 1997, Updated Demonstrated Reserve Base, San Juan Basin, NM, American Assoc. of Petroleum Geologists National Convention, Dallas, TX.
Hoffman, G.K., and Jones, G.E., 1998, Fruitland Coal Availability Study, Bisti Field, San Juan Basin New Mexico- A Preliminary Report: New Mexico Geological Society Annual Spring Meeting, Socorro, NM, New Mexico Geology vol. 20, no. 2, p. 50. Abstract
Hoffman, G.K., 1999, New Mexico's Coal Industry: New Mexico Geological Society Annual Spring Meeting, Socorro, NM, New Mexico Geology vol. 21, no. 2, p. 31. Abstract
Hoffman, G.K., and Jones, G. E., February 2000, Coal Availability Studies, Fruitland and Menefee Formations, San Juan Basin, New Mexico: Society of Mining, Metallurgy, and Exploration Annual Meeting, Salt Lake City, Utah. Abstract
Hoffman,
G.K., May 2000, Fly Ash Utilization in the Western United State: (Abs) 36th
Forum on the Geology of Industrial Minerals and 11th Extractive Industry Geology
Conference, Bath ,
England ,
Programme and Abstracts.
Hoffman, G.K., September 2000, Uses of Fly Ash from New Mexico Coals: American
Assoc. of Petroleum Geologists Rocky Mountain Section meeting, Albuquerque
, NM
Abstracts in American Assoc.
of Petroleum Geologists Bulletin vol. 84, no. 8., p. 1240.
Hoffman,
G.K., April, 2002, Fly Ash Utilization in the Western
United States ,: Coal Combustion By-products
and Western coal Mines: A Technical Interactive Forum, Denver
, Colorado
, Abstracts.
McLemore, V. T., Raugust, J. S., Hoffman, G. K , Wilks, M., Johnson, P., Krueger,
C. B., and Jones, G. E., 2003, Use of the New Mexico Mines Database in reclamation
studies: 20th Annual National Meetings of ASMR and the 9th Billings Land Reclamation
Symposium, Working Together for Innovative
Reclamation
McLemore, V. T., Krueger, C. B., Johnson, P., Raugust, J. S., Jones, G. E.,
Hoffman, G. K. and Wilks, M., 2003, New Mexico Mines Database (abstr.): Society
of Mining, Exploration, and Metallurgy, SME program,p. 58.