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Home Page of

Theodore J. Bornhorst

Emeritus Professor of Geology

 

 

 

Department of Geological and Mining Engineering and Sciences

Michigan Technological University

1400 Townsend Drive

Houghton, MI 49931

tjb@mtu.edu

 

Dr. Bornhorst is an Emeritus Professor of Geology at Michigan Tech. He was employed at Michigan Tech for 40 years. Most recently he was Executive Director and Interim Curator of the A.E. Seaman Mineral Museum of Michigan Tech as well as Professor of Geology. In his administrative role at the museum from 2003 to 2020 he was responsible for all aspects of the museum. Bornhorst was the museum leader in the relocation of the museum from its previous main campus location of 35 years to its current location into a newly constructed dedicated facility including a main museum building, mineral preparation annex, Phyllis and John Seaman garden, and copper pavilion. He was the Michigan Tech representative and the key person in negotiation of the Michigan Mineral Alliance, a unique agreement between Michigan Tech and the University of Michigan to preserve the legacy of the University of Michigan mineral collection, which now resides at the A. E. Seaman Mineral Museum. The alliance was highlighted in the journal Nature.

Prior to and during his administrative appointment in the museum, Bornhorst was a faculty member in the Department of Geological and Mining Engineering and Sciences engaged in teaching and research. His teaching responsibilities from 1980 to 2017 included: 35 years teaching various courses on metallic mineral deposits and exploration, 24 years teaching petrology, 32 years teaching field geology with engineering applications, and 3 years teaching mineralogy. He has also taught advanced courses in geochemistry, petrology, and mineral deposits. His research and that of the students he supervised have covered a breath of topics but with more emphasis on aspects of metallic mineral deposits, the geology and mineral resources of the Upper Peninsula of Michigan, geology and mineral resources in Finland, as well as topics involving environment, groundwater, and K-12 education. He has recently published articles on the genesis of native copper deposits of the Keweenaw Peninsula, the first published geologic description of the Copperwood sedimentary rock-hosted stratiform copper deposit, in the western Upper Peninsula, and an article in the international journal Economic Geology on humidity cell testing of for predicting future water-quality impacts from metallic mining. He was awarded the prestigious Goldich Medal in 2008 from the Institute on Lake Superior Geology for outstanding contributions to Lake Superior geology. Beginning in 2019, Bornhorst is the mineral deposits section Editor-in-Chief of the open access journal Minerals (https://www.mdpi.com/journal/minerals/editors).

EDUCATION

Ph.D. - 1980 - Geology - University of New Mexico

M.S. - 1976 - Geology - University of New Mexico

B.S. - 1974 (with high honor) - Geology - Michigan Technological University

AWARDS

Goldich Medal 2008 from the Institute on Lake Superior Geology for outstanding contributions to Lake Superior geology

Commendation from Michigan Governor Granholm for service to the State of Michigan in helping enact Michigan's landmark Sulfide Mining Act, Public Act 449 of 2004.

Geoscience Information Society Best Guidebook Award for 1995

PROFESSIONAL EXPERIENCE

Professor Emeritus, Department of Geological and Mining Engineering and Sciences, Michigan Technological University, Houghton, Michigan (September 2020 present).

Professor with tenure, Department of Geological and Mining Engineering and Sciences, Michigan Technological University, Houghton, Michigan (September 1993 to 2020).

Executive Director and Interim Curator, A. E. Seaman Mineral Museum, Michigan Technological University, Houghton, Michigan (2019 to 2020

Executive Director, A. E. Seaman Mineral Museum, Michigan Technological University, Houghton, Michigan (2015 to 2019)

Director, A. E. Seaman Mineral Museum, Michigan Technological University, Houghton, Michigan (2003 to 2015)

Special Assistant to the Dean of Engineering (2003 to 2007)

Chair, Department of Geological and Mining Engineering and Sciences, Michigan Technological University, Houghton, Michigan (1998 to 2003)

Adjunct Professor, Department of Education, Michigan Technological University, Houghton, Michigan (1996 to 2014)

Associate Professor with tenure, Department of Geological Engineering, Geology and Geophysics, Michigan Technological University, Houghton, Michigan (1986 to 1993)

Visiting Associate Professor, Geological Survey of Finland, Espoo (1991)

Assistant Professor, Department of Geology and Geological Engineering, Michigan Technological University, Houghton, Michigan (1981 to 1986).

Visiting Scientist, Mt. St. Helens Volcano Observatory, U.S.Geological Survey, Vancouver, Washington (1980)

Post-Doctoral Research Associate and Visiting Assistant Professor, Department of Geology and Geological Engineering, Michigan Technological University, Houghton, Michigan (1980 to 1981)

Visiting Staff Member, Chemistry-Nuclear Chemistry Group, Los Alamos Scientific Laboratory, Los Alamos, New Mexico (1977 to 1980)

Paid Consulting Activities: Marquette University, PolyMet Mining Corp. via Foth, Keweenaw Land Association, Orvana Resources Corp, Highland UPX, Phelps Dodge Exploration Corporation, Bell Resources Corporation, Grandcru Resources Corporation,  Steigerwaldt Land Services, International Paper, Peninsula Copper Industry, Red Metal Minerals, Copper Range Company, Michigan Low Level Radioactive Waste Authority, Callahan Mining Corporation, Battelle Memorial Institute, ARCO Exploration and Technology Group, Michigan Geological Survey, Amselco Exploration, Camden, South Carolina, Hanna Mining Company, Los Alamos Scientific Laboratory, Kennecott Exploration, Michigan Nature Association, Township of Eagle Harbor Michigan, Keweenaw Land Trust, The Nature Conservancy.

LICENSED PROFESSIONAL GEOLOGIST

State of Minnesota, Minnesota Board of Architecture, Engineering, Land Surveying (License Number 30247).

APPOINTMENTS

Mineral Deposits Section Editor-in-Chief of the open access journal Minerals published by Multidisciplinary Digital Publishing Institute (MDPI) (2019 to present)

Mineral Wells Advisory Committee of the Michigan Department of Environmental Quality (2001 to present), Vice Chair (2006 to ~2010).

Invited to be on the Community Advisory Group for Kennecott Eagle Project (2007 to 2008).

Charter Board Member of the Northern Michigan Geologic Repository Association (NMGRA) (2008-~2012)

Appointed to Work Group on Administrative Rules for Michigan's Nonferrous Metallic Mining Regulations, Part 632, Natural Resources and Environmental Protection Act, Act No. 451 of the Public Acts of 1994, as amended. (2005 to 2006); Only academic member.

Appointed to the Work Group on Regulation of Metallic Mineral Exploration and Mining in the State of Michigan. Appointed by the Director of the Michigan Department of Environmental Quality Director March 24, 2004. State of Michigan law which was passed by the Michigan Legislature and signed into law December 27, 2004 as Part 632, Natural Resources and Environmental Protection Act, Act No. 451 of the Public Acts of 1994, as amended; Only academic member.

Appointed to the Work Group on Metallic Mineral Leasing of State of Michigan Mineral Rights. (March to August, 2004). Only academic member.

Appointed to the Board of Governors of Michigan's Low-Level Radioactive Waste Research and Education Institute. The Board of Governors was convened in accordance with 1995 amendments to Section 17 (13) of Michigan Public Act 204. Appointed by Commissioner of the Michigan Low-Level Radioactive Waste Authority. Term of Appointment March 1, 1995 to March 1, 1998. Board disbanded by Michigan Governor.

Appointed as Chairperson of the Siting Criteria Advisory Committee for Michigan's Low Level Radioactive Waste Authority. The committee was mandated by the Michigan legislature, Public Act 204, 1987. Appointment by Commissioner and Head of the Authority, David Hales; Chairperson - January 1988 to May, 1989.

Appointed to the Board of Governors of the International Low-Level Radioactive Waste Research and Education Institute. The institute was created by section 17 of Michigan Public Act 204 of 1987 and operated by a consortium from the University of Michigan and Michigan State University. Appointment by Michigan Low-Level Radioactive Waste Authority, University of Michigan, and Michigan State University. Term of Appointment March 22, 1989 to October 1, 1992 when committee was disbanded by Michigan Governor Engler upon withdrawal from the Midwest Low-Level Radioactive Waste Compact).

Appointed by Governor Blanchard, State of Michigan to the Radioactive Waste Control Committee legislated by Michigan Public Act 190 of 1985; term of appointment March 7, 1986 to April 15, 1988 (committee disbanded upon creation of the Low-level Radioactive Waste Authority).

Appointment confirmed by Governor Blanchard, State of Michigan, to Governor's Task Force on High-Level Radioactive Waste; Member July 1983 to April 1986 (committee disbanded when DOE ended search for crystalline rock site).

Appointed by Governor Blanchard's Office to be one of three state representatives at the Department of Energy's "States Weighting Workshop", Crystalline Rock Project held at Battelle Memorial Institute, Columbus, Ohio, May 20-22, 1985.

PROFESSIONAL SOCIETIES

Fellow Geological Society of America

Fellow Society of Economic Geologists

Fellow Geological Association of Canada

Member American Geophysical Union

Member Institute on Lake Superior Geology

SERVICE TO PROFESSIONAL ORGANIZATIONS

Co-Chair, Institute on Lake Superior Geology, 2017.

Principal Co-Chair, Board of Directors, Institute on Lake Superior Geology, 2008

Board of Directors, Institute on Lake Superior Geology, 2008-2011

Presenter and Organizer

Short Course for 44th Annual Meeting of the American Institute of Professional Geologists held in Traverse City, MI; Exploration for and Mining of Metals with Emphasis on Michigan Upper Peninsula (8 hours of presentations and discussion), 2007

Principal Co-Chair, Board of Directors, Institute on Lake Superior Geology, 1999

Board of Directors, Institute on Lake Superior Geology, 1999-2002

Executive Committee (1999-2001), U.S. Heads and Chairs of Earth and Space Science Departments within American Geophysical Union (Chair through October, 2000, Past Chair and member until October 2001) organized two day meeting held in Washington DC October 19 and 20, 2000 attended by about 50 department heads/chairs from across the U.S

Society of Economic Geologists, Short Course Committee, 1996-1999

Associate Secretary Treasurer, Institute on Lake Superior Geology, 1994-1999

Chair, Board of Directors, Institute on Lake Superior Geology, 1994

Board of Directors, Institute on Lake Superior Geology, 1994-1998

Principal Organizer of Society of Economic Geologists Field Conference, western Upper Michigan, 1992

Chair, Board of Directors, Institute on Lake Superior Geology, 1983

Board of Directors, Institute on Lake Superior Geology, 1983-1987

EDITORSHIP

Bornhorst, T.J., 2018, Geochemistry and Mineralogy of Hydrothermal Metallic Mineral Deposits: Minerals Special Issue

Bornhorst, T.J. and Hanson, M.J., editors, 2017, Institute on Lake Superior Geology, Proceedings Part 2: Field Trip Guidebook, 63rd Annual Meeting, Wawa, Ontario v. 63, part 2, 204p.

Bornhorst, T.J. and Hanson, M.J., editors, 2017, Institute on Lake Superior Geology, Proceedings Part 1: Program and Abstracts, 63rd Annual Meeting, Wawa, Ontario v. 63, part 1, 97p.

Bornhorst, T.J. and Barron, R.J., editors, 2013, Institute on Lake Superior Geology, Proceedings, Field Trip Guidebook, 59th Annual Meeting, Houghton, MI v. 59, part 2, 118p.

Blaske, A.R. and Bornhorst, T.J., editors, 2013, Institute on Lake Superior Geology, Proceedings, Program and Abstracts, 59th Annual Meeting, Houghton, MI v. 59, part 1, 83p.

Bornhorst, T.J. and Klasner, J.S., editors, 2008, Institute on Lake Superior Proceedings Volume 54, Field Trip Guidebook, published by Institute on Lake Superior Geology, St. Paul, MN, v. 54, part 2, 85p.

Bornhorst, T.J. and G.W. Robinson, editors, 2008, Institute on Lake Superior Proceedings Volume 54, Program and Abstracts, published by Institute on Lake Superior Geology, St. Paul, MN, v. 54, part 1, 85p.

Woodruff, Laurel and Bornhorst, T.J. editors, 2003, Institute on Lake Superior Proceedings Volume 49, Program and Abstracts, published by Institute on Lake Superior Geology, St. Paul, MN, v. 49, part 1, 85p.

Bornhorst, T.J., editor, 1999, Institute on Lake Superior Geology Proceedings Volume 45, Field Trip Guidebook, published by Institute on Lake Superior Geology, St. Paul, MN, v. 45, part 2, 176p.

Regis, R.S., and Bornhorst, T.J., editors, 1999, Institute on Lake Superior Geology Proceedings Volume 45, Program and Abstracts, published by Institute on Lake Superior Geology, St. Paul, MN, volume 45, part 1, 62p.

Bornhorst, T.J., editor, 1998, ILSG Newsletter, published by the Institute on Lake Superior Geology, distribution of 600 copies mostly within U.S. and Canada with some to Europe, Number 1 published December 1995, Number 2 published December 1996, Number 3 published December 1997, Number 4 published December 1998.

Bornhorst, T.J., 1997, Guest Editor for a special issue of the Canadian Journal of Earth Sciences, Petrology and Metallogeny of Intraplate Mafic and Ultramafic Magmatism, published April 1997, 238 pages; total of 36 manuscript reviews.

Bornhorst, T.J. and McDowell, S.D., editors, 1994, Institute on Lake Superior Geology Proceedings, Program and Abstracts, 40th Annual Meeting, Houghton, MI, v. 40, part 1, 84p.

Bornhorst, T.J., editor, 1992, Keweenawan Copper Deposits of Western Upper Michigan, Society of Economic Geologists Guidebook Series, v. 13, 197 p.

Bornhorst, T.J. and Diehl, J.F., co-editors, 1983, Institute on Lake Superior Geology Proceedings 29th Annual Meeting, Houghton, MI, v. 29, 81 p.

PUBLICATIONS

Bornhorst, T.J., 2018, Editorial for Special Issue on Geochemistry and Mineralogy of Hydrothermal Metallic Mineral Deposits: Minerals 2018, v. 8, p. 251 doi:10.3390/min8060251

Bornhorst, T.J. and Mathur, R., 2018, Copper Isotope Constraints on the Genesis of the Keweenaw Peninsula Native Copper District, Michigan, USA: Reply: Minerals, v. 8, p. 508, 8p. doi:10.3390/min8110508.

Bornhorst, T.J., 2018, Maximum depositional age of the Neoproteroaoic Jacobsville Sandstone, Michigan: Implications for the evolution of the Midcontinent Rift: COMMENT: Geoshpere, v. 14, no. 3, 2p. doi:10.1130/GES01575.1.

Bornhorst, T.J., Poulsen, C.J., and Ewing, R.C., 2018, A rescue package for imperilled collection: Nature, Correspondence, v. 546, p. 210.

Boerboom, T.J., Bornhorst, T.J., Cannon, W.F., Hinze, W.J., Jirsa, M.A., Runkel, A.C., Schulz, K.J., Steenberg, J.R., and Woodruff, L.G., 2018, Comment on Paleozoic reactivation structures in the Appalachian-Ouachita-Marthon foreland: Far-field Deformation across Pangea, by J. Craddock, D. Malone, R. Porter, J. Compton, J. Luczaj, A. Konstantinou, J. Day, and S. Johnston [Earth Science Reviews 169 (2017), 1-34]: Earth Science Reviews, v. 181, 144-152. doi.org/10.1016/j.earscirev.2018.02.003.

Bornhorst, T.J. and Mathur, R., 2017, Copper Isotope Constraints on the Genesis of the Keweenaw Peninsula Native Copper District, Michigan, USA: Minerals, v. 7, p. 185, 20p. doi:10.3390/min7100185.

Bornhorst, T.J., and Logsdon, M.J., 2016, Predicting Future Water-Quality Impacts from Mining: A 52-year Old Field Analog for Humidity Cell Testing, Copperwood Deposit, Michigan, Economic Geology, v. 111, p. 527-542.                                                                      

Ikehata, K., Chida, K., Tsunagae, T., and Bornhorst, T.J., 2016, Hydrothermal Native Copper in Ocean Island Alkali Basalt from Mineoka Belt, Boso Peninsula, Central Japan: Economic Geology, v. 111, p. 783-794..

Bornhorst, T.J. and Poulsen, C.J., 2015, Michigan Mineral Alliance, Rocks & Minerals, v. 90, p. 450-453.

Bornhorst, T.J. and Williams, W.C., 2013, The Mesoproterozoic Copperwood Sedimentary Rock-Hosted Stratiform Copper Deposit, Upper Peninsula, Michigan: Economic Geology, v. 108, p. 1325-1346.

Bornhorst, T.J. and Barron, R.J., 2013, Geologic Overview of the Keweenaw Peninsula, Michigan Field Trip 1: Institute on Lake Superior Geology, Field Trip Guidebook, 59th Annual Meeting, Houghton, MI v. 59, part 2, p. 1-42.

Bornhorst, T.J., Barron, R.J., and Whiteman, R.C., 2013, Caledonia Mine, Keweenaw Peninsula Native Copper District, Ontonagon County, Michigan Field Trip 2: Institute on Lake Superior Geology, Field Trip Guidebook, 59th Annual Meeting, Houghton, MI v. 59, part 2, p. 43-57.

Bornhorst, T.J., Blaske, A., Anderson, D, Repaal, T.D., 2013, Geology and Environmental Site Conditions of the Copperwood Deposit, Gogebic County, Michigan Field Trip 6: Institute on Lake Superior Geology, Field Trip Guidebook, 59th Annual Meeting, Houghton, MI v. 59, part 2, p. 97-118.

Bornhorst, T.J., and Barron, R.J., 2011, Copper deposits of the western Upper Peninsula of Michigan: Geological Society of America Field Trip Guide 24, p. 83-99.

Bornhorst, T.J., and Brandt, D., 2009, Michigans earliest geology: The Precambrian: in Schaetzl, R., Darden, J., and Brandt, D., eds., Michigan Geography and Geology, Pearson Custom Publishing, New York, p. 24-39.

Bornhorst, T.J., and Lankton, L.D., 2009, Copper mining: A billion years of geologic and human history: in Schaetzl, R., Darden, J., and Brandt, D., eds, Michigan Geography and Geology, Pearson Custom Publishing, New York, p. 150-173.

Rasilainen, K., Lahtinen, R., and Bornhorst, T. J., 2008, Chemical characteristics of Finnish bedrock 1:1000000 scale bedrock map units: Geological Survey of Finland, Report of Investigation 171, 96p.

Rasilainen, K., Lahtinen, R. and Bornhorst, T. J., 2007. The Rock Geochemical Database of Finland Manual. Geological Survey of Finland, Report of Investigation 164, 38 p. The Rock Geochemical Database of Finland (online database): http://www.gtk.fi/publ/RGDB.

Rasilainen, K., Lahtinen, R. and Bornhorst, T.J., 2007, The Rock Geochemistry Database of Finland - a new tool for large scale exploration and crustal studies. In: Andrew, C.J. et al. (eds.) Digging deeper, Ninth biennial meeting of the Society for Geology Applied to Mineral Deposits, Dublin, Ireland 20th-23rd August 2007, p. 1267-1270.

Bornhorst, T.J., and Lankton, L.D., 2006, Keweenaw Copper: Geology and History, published by Great Lakes Geoscience LLC, Ontonogan, MI, 2006, 30 p.

Karkkainen, N. K. and Bornhorst, T.J., 2003, The Svecofennian gabbro-hosted Koivusaarenneva magmatic ilmenite deposit, Kalvia, Finland, Mineralium Deposita, v. 38, p. 169-184.

Nurmi, P.A., Bornhorst, T. J., and Rasilainen, K., 2001, Pathfinder Elements for Hydrothermal Gold Mineralization: From General to Case Studies: Proceedings of 2001: A Hydrothermal Odyssey, James Cook University Economic Geology Research Unit Contribution 59, May 17 - 19, 2001, Townsville, Australia, p. 156-157.

Pregitzer, K.S., Reed, D.D., Bornhorst, T.J., Foster, D.R., Mroz, G.D., McLachlan, J.S., Laks, P.E., Stokke, D.D., Martin, P.E., Brown, S.E., 1999, A buried spruce forest provides evidence at the stand and landscape scale for the effects of environment on vegetation at the Pliestocene/Holocene boundary: Journal of Ecology, v. 88, p. 1-10.

Bornhorst, T.J., 1999, Geologic Setting of the Tilden and Empire Mines, Michigan: Institute on Lake Superior Geology, Field Trip Guidebook, 45th Annual Meeting, v. 45, part 2, p. 108-113.

Johnson, R.C., and Bornhorst, T.J., Geologic Field Excursion to the Ishpeming Greenstone Belt: Institute on Lake Superior Geology, Field Trip Guidebook, v. 45, part 2, p. 45-56.

Bornhorst, T.J. and Bair, S.E., 1999, Introduction to the Ropes gold deposit in the Ishpeming Greenstone Belt, Michigan: Institute on Lake Superior Geology, Field Trip Guidebook, v. 45, part 2, p. 29-44.

Johnson, R.C., and Bornhorst, T.J., 1999, An Introduction to the Archean Ishpeming Greenstone Belt, Michigan: Institute on Lake Superior Geology, Field Trip Guidebook, v. 45, part 2, p. 12-28.

Bornhorst, T.J., Nurmi, P.A., and Kontoniemi, O., 1998, Geochemistry of gold and associated elements in the Paleoproterozoic Osikonmaki gold deposit, southeastern Finland: Geological Survey of Finland Special Paper 25, p. 81-90.

Bornhorst, T.J., Thorpe, R.I., and Johnson, R.C., 1998, Lead isotope study of veins in the Archean Ishpeming greenstone belt, Michigan: Economic Geology, v. 93, p. 102-107.

Wahyudi, T., Bornhorst, T.J., and Nesbitt, C., 1998, A comparative study of cyanide and bromine recovery of gold from a roasted Osikonmaki gold ore, Finland: Geological Survey of Finland Special Paper 25, p. 111-119.

Taylor, L.G., and Bornhorst, T.J., 1998, A boiling model for the formation of enargite-bearing veins in the Central City district, Colorado: The Mountain Geologist, v. 35, p. 15-22.

Bornhorst, T.J., 1997, Tectonic context of native copper deposits of the North American Midcontinent rift system: Geological Society of America Special Paper, 312, p. 127-136.

Marshak, S., Tinkham, D., Alkmim, F.F., Brueckner, H., Bornhorst, T., 1998, REPLY: Dome-and-keel provinces formed during Paleoproterozoic orogenic collapse: Geology, v. 26, p. 475-477.

Marshak, S., Tinkham, D., Alkmin, F., Brueckner, H., and Bornhorst, T., 1997, Dome-and-keel provinces formed during Paleoproterozoic orogenic collaspe-core complexes, diapirs, or neither?: Examples from the Quadrilatero Ferrifero and the Penokean orogen: Geology, v. 25, p. 415-418.

Nurmi, P.A., Bornhorst, T.J., and Kontas, E., 1997, Trace element signature of selected gold deposits in the Fennoscandian Shield and the North American Continent: in Papunen, H., ed., Mineral Deposits: Research and Exploration Where do They Meet?, Balkema, Rotterdam, p. 253-255.

Bornhorst, T.J., 1997, Preface, Canadian Journal of Earth Sciences, v. 34, no. 4, p. v-vi.

Bornhorst, T.J., 1997, Evolution of ore-bearing Precambrian structures: in Books for Geoscientists, Journal of Geoscience Education, v. 45, p. 87.

Bornhorst, T.J., Nurmi, P.A., Rasilainen, K., and Kontas, E., 1995, Trace element characteristics of selected epithermal gold deposits of North America: Geological Survey of Finland Special Paper 20, p. 47-52.

Bornhorst, T.J., 1995, Relationship between native copper deposits and tectonic development of the North American Midcontinent rift system: in Ojakangas, R.W. et al. (eds.), Basement Tectonics 10, Balkema, Rotterdam, p. 19-23.

Woodruff, L.G., Bornhorst, T.J., and Nicholson, S.W., 1995, Overview - Stratigraphy, structure, and ore deposits of the southern limb of the Midcontinent rift system: Minnesota Geological Survey Guidebook Series No. 20, "Field trip guidebook for the geology and ore deposits of the Midcontinent rift in the Lake Superior region," p. 73-80.

Bornhorst, T.J., 1995, Native copper in basalts of the Keweenaw Pensinsula: Minnesota Geological Survey Guidebook Series No. 20, "Field trip guidebook for the geology and ore deposits of the Midcontinent rift in the Lake Superior region," p. 97-104.

Bornhorst, T.J. and Rose, W.I., 1994, Self-guided geological field trip to the Keweenaw Peninsula, Michigan: Institute on Lake Superior Geology Proceedings, Field Trip Guidebook, v. 40, part 2, 185p. (4500 copies sold from May 1994 to 2014).

Bornhorst, T.J., Rasilainen, K., and Nurmi, P.A., 1993, Geochemical character of lithologic units in the Late Archean Hattu schist belt, Ilomantsi, eastern Finland: Geological Survey of Finland Special Paper 17. p. 133-145.

Bornhorst, T.J., and Rasilainen, K., 1993, Mass transfer during hydrothermal alteration associated with Au mineralization within the late Archean Hattu schist belt, Ilomantsi, eastern Finland: Geological Survey of Finland Special Paper 17, p. 273-289.

Bornhorst, T.J., and Wilkin, R.T., 1993, Fluid inclusion data for selected quartz from gold prospects in the Hattu schist belt, Ilomantsi, Finland: Geological Survey of Finland Special Paper 17, p. 317-322.

Bornhorst, T.J., and Johnson, R.C., 1993, Geology of volcanic rocks in the southern half of the Archean Ishpeming greenstone belt, Michigan: U. S. Geological Survey Bulletin 1904-P, 13p.

Wilkin, R.T., and Bornhorst, T.J., 1993, Archean appinites from the northern complex, Michigan: Journal of Geology, v. 101, p. 107-114.

Rasilainen, K., Nurmi, P.A., and Bornhorst, T.J., 1993, Rock geochemical implications for gold exploration in the Late Archean Hattu schist belt, Ilomantsi, eastern Finland: Geological Survey of Finland Special Paper 17, p. 353-362.

Wilkin, R.T., and Bornhorst, T.J., 1992, Geology and geochemistry of granitoid rocks in the Archean northern complex, Michigan, U.S.A.: Canadian Journal of Earth Sciences, v. 29, p. 1674-1685.

Bornhorst, T.J., 1992, Relationship between native copper deposits and tectonic development of the North American Midcontinent rift system: 10th International Basement Tectonics Conference Program with Abstracts, p. 191-193.

Bornhorst, T.J., 1992, An overview of the Keweenaw Peninsula native copper district, Michigan: Society of Economic Geologists Guidebook Series, v. 13, p. 33-62.

Bornhorst, T.J. and Whiteman, R.C., 1992, The Caledonia native copper mine, Michigan, Society of Economic Geologists Guidebook Series, v. 13, p. 139-144.

Bornhorst, T.J., 1992, Road log of bedrock geology and native copper deposits of the Keweenaw Peninsula, Michigan: Society of Economic Geologists Guidebook Series, v. 13, p. 105-138.

Bornhorst, T.J. and McDowell, S.D., 1992, Michigan Tech Earth Science Laboratory and Experimental Mine connecting with the Quincy Native Copper Mine, Michigan: Society of Economic Geologists Guidebook Series, v. 13, p. 100-104.

Bornhorst, T.J., 1992, Keweenaw Peninsula: in South Flank of Mid-Proterozoic Midcontinent Rift and Archean and Lower Proterozoic Basement, Wisconsin and Michigan, editor J.C. Green, 10th International Basement Tectonics Conference Field Trip Guidebook, p. 42-69.

Blaske, A.R., Bornhorst, T.J., Brady, J.M., Marsh, T.M., McKitrick, S.A., 1991, The Shumake volcanic dome-hosted epithermal, precious metal deposit, western Mojave Desert, California: Economic Geology, v. 86, p. 1646-1656.

Johnson, R.C., and Bornhorst, T.J., 1991, Archean geology of the northern block of the Ishpeming greenstone belt, Marquette County, Michigan: U. S. Geological Survey Bulletin 1904-F, p. F1-F20.

Bornhorst, T.J., 1991, Global Volcanism 1976-1985: The first decade of reports from the Smithsonian Institution's scientific alert network (SEAN): in Books for Geoscientists, Journal of Geological Education, v. 39, p. 154.

Bornhorst, T.J., 1991, Copper deposits and host rocks, western Upper Peninsula of Michigan: Minnesota Geological Survey Information Circular 34, p. 64-72 (Proceedings of U.S.A.-U.S.S.R.-Canada Joint Seminar on Precambrian geology of the southern Canadian shield and the eastern Baltic Shield held August, 1990, Duluth, Minnesota).

Bornhorst, T. J., 1990, The Volcano Letter: in Books for Geoscientists, Journal of Geological Education, v. 38, p. 257-258.

Bornhorst, T.J., 1989, A field guide to the Keweenaw Peninsula native copper district: Society of Economic Geologists Fall Field Conference Guidebook, October 1-5, 1989, p. 116-141.

Bornhorst, T.J., Kalliokoski, J., Paces, J.B., and Rose, W.I., Jr., 1989, Stops 30 to 40: Lake Superior Basin Segment of the Mid-Continent Rift System: 28th International Geological Congress, Field Trip Guide Book T344, p. T344-43-T344-51 (published by American Geophysical Union).

Bornhorst, T.J., 1988, Character of mid-Cenozoic andesites, basaltic andesites and related volcanic rocks, Mogollon-Datil volcanic field, southwestern New Mexico: Colorado School of Mines Quarterly, v. 83, no. 1, p. 1-13.

Bornhorst, T.J., 1988, Gold in mantle peridotites from Upper Proterozoic ophiolites in Arabia, Mali, and Morocco - A discussion: Economic Geology, v. 83, p. 1285.

Bornhorst, T.J., Paces, J.B., Grant, N.K., Obradovich, J.D. and Huber, N.K., 1988, Age of native copper mineralization, Keweenaw Peninsula, Michigan: Economic Geology, v. 83, p. 619-625.

Bornhorst, T.J., 1988, Granophile elements in mid-Cenozoic calc-alkalic rhyolitic volcanic rocks, Mogollon-Datil volcanic field, southwestern New Mexico: Canadian Institute of Mining, Special Volume 39, p. 331-341.

Bornhorst, T.J., 1988, Geological overview of the Marquette greenstone belt, Michigan: 34th Annual Insititue on Lake Superior Geology, Field Trip Guidebooks, v. 34, p. A1-A18.

Diehl, J.F., McClannahan, K.M., and Bornhorst, T.J., 1988, Paleomagnetic results from the Mogollon-Datil volcanic field, southwestern New Mexico and a mid-Tertiary reference pole for North America: Journal of Geophysical Research, v. 93, p. 4869-4879.

Li, G., Whitten, E.H.T., Bornhorst, T.J., and Hicks, D.L., 1988, Subdivision among samples on the basis of numerous variables: The Compass of Sigma Gamma Epsilon, v. 66, no. 1, p. 7-14.

Halsor, S.P., Bornhorst, T.J., Strowd, W., Beebe, M. and Richardson, K., 1988, The geology of the DeLamar Silver Mine, Idaho - A volcanic dome complex and genetically associated hydrothermal system:  Economic Geology, v. 83, p. 1159-1169.

Bornhorst, T.J., 1988, Road Log Stops 7, 9, 10, and 14: in Upper Keweenawan rift-fill sequence, mid-continent rift system, Michigan: Michigan Basin Geological Society 1988 Fall Field Trip Guidebook, p. 53-60, 69-70.

Bornhorst, T.J., Baxter, D.A., MacLellan, M.L., and Johnson, R.C., 1988, Geological field trip to the Marquette Greenstone Belt: Part I, Day 1 Road Log - Stops 1 to 11: Institute on Lake Superior Geology, Field Trip Guidebooks, v. 34, Part 2, p. A54-A64.

Bornhorst, T.J. and Baxter, D.A., 1988, Geological field trip to the Marquette Greenstone Belt: Part II, Day 2 Road Log - Stops A to E: Institute on Lake Superior Geology, Field Trip Guidebooks, v. 34, Part 2, p. A65-A71.

Green, J.C., Bornhorst, T.J., Chandler, V.W., Mudrey, M.G., Jr., Myers, D.E., Pesonen, L., and Wilband, J.T., 1987, Late-middle Proterozoic (Keweenawan) dykes of the western Lake Superior region: Evidence for evolution of the North American midcontinent rift: Geological Association of Canada Special Paper 34, p. 289-302.

Tilling, R.I., Bornhorst, T.J., Taggart, J.E., Jr., Rose, W.I., and McGee, J.J., 1987, Inter-laboratory comparisons of X-ray fluorescence analyses of eruptive products of El Chichon volcano, Chiapas, Mexico: Applied Geochemistry, v. 2, p. 337-345.

Rose, W.I., Jr., Newhall, C.G., Bornhorst, T.J., and Self, S., 1987, Quaternary silicic pyroclastic deposits of Atitlan caldera, Guatemala: Journal of Volcanology and Geothermal Research, v. 33, p. 57-80.

Whitten, E.H.T., Li, G., Bornhorst, T.J., Christenson, P., and Hicks, D.L., 1987, Quantitative recognition of granitoid suites within batholiths and other igneous assemblages: in Use and Abuse of Statistical Methods in the Earth Sciences, International Association of Mathematical Geology, Studies in Mathematical Geology, No. 1, p. 55-73.

Bauer, G.R., Fodor, R.V., Jacobs, R.S., and Bornhorst, T.J., 1987, Kahoolawe Island, Hawaii: Initial geochemical investigation of its tholeiitic, alkalic, and unusual "enrichment" characteristics: Journal of Volcanology and Geothermal Research, v. 31, p. 171-176.

Whitten, E.H.T., Bornhorst, T.J., Li, G., Hicks, D.L., and Beckwith, P., 1987, Suites: Suites, subdivision of batholiths, and igneous rock classification: Geological and mathematical conceptualization: American Journal of Science, v. 287, no. 4, p. 332-352.

Bornhorst, T.J., Shepeck, A.W. and Rossell, D.M., 1986, The Ropes gold mine, Marquette County, Michigan, U.S.A.: An Archean hosted lode gold deposit: in MacDonald, A.J., Ed., Proceedings of Gold 86, an International Symposium on the Geology of Gold, Toronto, 1986, p. 213-227.

Bornhorst, T.J. and Rose, W.I., Jr., 1986, Partitioning of gold in young calc-alkalic volcanic rocks from Guatemala: Journal of Geology, v. 94, p. 412-418.

Rose, W.I., Jr., Bornhorst, T.J., and Sivonen, S.J., 1986, Rapid and high quality major and trace element analyses of powdered rock by X-ray fluorescence spectrometry: X-Ray Spectrometry, v. 15, p. 55-60.

Bornhorst, T., Kalliokoski, J., and Paces, J., 1986, The Keweenaw Native-Copper District: in Brown, A.C. and Kirkham, R.V. (eds.), Proterozoic sediment-hosted stratiform copper deposits of Upper Michigan and Belt Supergroup of Idaho and Montana, Geological Association of Canada, Mineralogical Association of Canada, Canada Geophysical Union, Joint Annual Meeting, Ottawa '86, Field Trip 1: Guidebook, p. 21-36.

Bornhorst, T.J., 1985, Abundance and variability of selected lithophile elements in high-K rhyolitic volcanic rocks, Mogollon-Datil volcanic field, southwestern New Mexico: International Canadian Institute of Mining Conference on Granite-Related Mineral Deposits, Halifax, Nova Scotia, Canada, editors R.P. Taylor and D.F. Strong, p. 25-31.

Bornhorst, T.J. and Kent, G.R., 1985, Geochemistry of host rock alteration at the Eberle Mine, Mogollon mining district, southwestern New Mexico: New Mexico Bureau of Mines and Mineral Resources Circular 199, p. 7-15.

Bornhorst, T.J. and Wolfe, S.P., 1985, Abundance of silver in mid-Cenozoic volcanic rocks of the Mogollon-Datil volcanic field, southwestern New Mexico: New Mexico Bureau of Mines and Mineral Resources Circular 199, p. 41-43.

Green, J.C., Bornhorst, T.J., Chandler, V.W., Mudrey, M.G., Jr., Myer, P.E., Pesonen, L. and Wilband, J.T., 1985, Late-middle Proterozoic (Keweenawan) dykes of the western Lake Superior region: Evidence for evolution of the North American mid-continent rift: International Conference on Mafic Dyke Swarms, Mississaugo, Canada, editor H.C. Halls, p. 59-61.

Bornhorst, T.J., Kent, G.R., Mann, K.L., and Richey, S.R., 1984, Temperature of mineralization in Mogollon mining district and vicinity, southwest New Mexico: New Mexico Geology, v. 6, p. 53-55.

Bornhorst, T.J., Rose, W.I.,Jr., Wolfe, S.P., and Hoffman, 1984, Gold content of eleven French geochemical reference standards: Geostandards Newsletter, v. 8, p. 1-2.

Rose, W.I., Jr., Bornhorst, T.J., Halsor, S.P., Capaul, W.A., Plumley, P.S., de la Cruz-Reyna, S., Mena, M., and Mota, R., 1984, Volcan el Chichon, Mexico: Pre-1982 S-rich eruptive activity: Journal of Volcanology and Geothermal Research, v. 23, p. 147-167.

Bornhorst, T.J. and Brookins, D.G., 1983, Sr isotopic initial ratios for mid-Cenozoic volcanic rocks from the Mogollon-Datil volcanic field, southwestern New Mexico: Isochron/West, no. 36, p. 13-15.

Drexler, J.W., Bornhorst, T.J., and Noble, D.C., 1983, Trace-element potassium feldspar/glass distribution coefficients for peralkaline silicic rocks: Lithos, v. 16, p. 265-271.

Stuart, E.J., Bornhorst, T.J., Rose, W.I., Jr., and Noble, D.C., 1983, Distribution and mobility of uranium and thorium in the peralkaline Soldier Meadow Tuff, northwestern Nevada: Economic Geology, v. 78, p. 353-358.

Bornhorst, T.J., Rose, W.I., Jr., and Paces, J.B., 1983, Field guide to the geology of the Keweenaw Peninsula, Michigan: Institute on Lake Superior Geology Proceedings, v. 29, 116 p. (1800 total copies sold from May 1983 to May 1994).

Bornhorst, T.J., Jones, D.P., Elston, W.E., Damon, P.E., and Shafiquallah, M., 1982, New radiometric ages on volcanic rocks from the Mogollon-Datil volcanic field, southwestern New Mexico: Isochron/West, no. 35, p. 13-14.

Rose, W.I., Jr., Bornhorst, T.J., and Drexler, J.W., 1982, Preliminary correlation of Quaternary volcanic ashes from the middle America trench off Guatemala, Deep Sea Drilling Project Leg 67: in Aubuoin, J. von Huene, R., et al., Initial Reports DSDP 67, Washington (U.S. Gov`t. Printing Office), p. 493-495.

Bornhorst, T.J. and Elston, W.E., 1981, Uranium and thorium in mid-Cenozoic rocks of the Mogollon-Datil volcanic field, southwestern New Mexico: American Association of Petroleum Geologists Studies in Geology, No. 13, Uranium in Volcanic and Volcaniclastic Rocks, p. 145-154.

Rose, W.I., Jr., and Bornhorst, T.J., 1981, Concentrations and isotropic distribution of uranium and thorium in selected Quaternary volcanic rocks from Guatemala and Sumatra: Evidence for uranium redistribution: American Association of Petroleum Geologists Studies in Geology, No. 13, Uranium in Volcanic and Volcaniclastic Rocks, p. 13-21.

Casadevall, T.J., Johnston, D.A., Harris, D.M., Rose, W.I., Jr., Malinconico, L.L., Stoiber, R.E., Bornhorst, T.J., Williams, S.N., Woodruff, L., and Thompson, J.M., 1981, SO2 emission rates at Mount St. Helens: March 29 to November 1, 1980: U.S. Geological Survey Bulletin 1250, p. 193-200.

Harris, D.M., Sato, M., Casadevall, T.J., Rose, W.I., Jr., and Bornhorst, T.J., 1981, Emission rates of CO2 at Mount St. Helens volcano: U.S. Geological Survey Bulletin 1250, p. 201-207.

Fodor, R.V., Kumar, K., Bornhorst, T.J., and Husler, J.W., 1980, Petrology of basaltic rocks from the Sao Paulo ridge, southwestern Atlantic Ocean: Marine Geology, v. 36, p. 127-141.

Bornhorst, T.J. and Balagna, J.P., 1979, Instrumental neutron activation analysis of French geochemical samples: Geostandards Newsletter, v. 3, p. 177-180.

Lopez, D.A. and Bornhorst, T.J., 1979, Geologic map of the Datil area, Catron County, New Mexico: U.S. Geological Survey Miscellaneous Investigations Map I-1098, 1 sheet, 1:50,000.

Elston, W.E. and Bornhorst, T.J., 1979, The Rio Grande rift in context with post-40 m.y. volcanic and tectonic events, in Rio Grande Rift: Tectonics and Magmatism, American Geophysical Union Special Publication, p. 416-438.

Bornhorst, T.J. and Elston, W.E., 1978, Road log from Reserve, New Mexico to Magdalena, New Mexico via Horse Springs and Datil: New Mexico Geological Society Special Publication Number 7, p. 99-105

Bornhorst, T.J., Erb, E.E., and Elston, W.E., 1976, Reconnaissance geologic map of the Mogollon-Datil volcanic province: New Mexico Geological Society Geologic Map, 2 sheets, 1:350,000.

Rhodes, R.C. and Bornhorst, T.J., 1976, Petrologic provinces in Jurassic tholeiites of Gondwanaland: Geologische Rundschau, v. 65, p. 930-938.

Rhodes, R.C. and Bornhorst, T.J., 1975, Applications of discriminant function analysis to the felsic rocks of the Bushveld Complex, South Africa: Lithos, v. 8, p. 193-197.

Bornhorst, T.J. 1975, Petrochemistry of the Fish Cove rhyolite, Keweenaw Peninsula, Michigan, U.S.A.: Chemical Geology, v. 15, p. 295-302.

PUBLISHED ARCHIVAL REPORTS

Wilkin, R.T., Johnson, R.C. and Bornhorst, T.J., 1992, Bedrock geologic map of the Negaunee NW quadrangle, Marquette County, Michigan: Contribution to Michigan Geology 92-2, (map 1:24000), published by Michigan Geological Survey.

Wilkin, R.T. and Bornhorst, T.J., 1992, Geochemical data for bedrock samples from the Negaunee NW quadrangle, Marquette County, Michigan: Contribution to Michigan Geology 92-3, 9 p., published by Michigan Geological Survey.

Wilkin, R.T. and Bornhorst, T.J., 1990, Geology of the Boise Creek area, Marquette greenstone belt, Michigan: Contribution to Michigan Geology Report 90-3, 15 p. and map (1:6000), published by Michigan Geological Survey.

Small, J.R. and Bornhorst, T.J., 1990, Precambrian geology of the Penny Lake area, Marquette greenstone belt, Michigan: Contribution to Michigan Geology Report 90-1, 26 p. and map (1:6000), published by Michigan Geological Survey.

Bornhorst, T.J. and Baxter, D.A., 1990, Reconnaissance evaluation of platinum-group elements in selected Precambrian rocks of the western Upper Peninsula, Michigan: Contribution to Michigan Geology Report 90-2, 30 p, published by Michigan Geological Survey.

MacLellan, M.L. and Bornhorst, T.J., 1989, Bedrock geology of the Reany Lake area, Marquette County, Michigan: Michigan Geological Survey, Department of Natural Resources, Open-File Report, OFR-89-2, 111 p. and map (1:6000).

Blaske, A., Bornhorst, T.J., Johnson, A.M., Frantti, G.E., and Reed, R.C., 1988, Manganese investigation in Keweenaw County, Michigan: Michigan Geological Survey, Department of Natural Resources, Open-File Report, OFR-88-2, 36 p.

Bornhorst, T.J., 1988, Geological overview of the Marquette Greenstone Belt, Michigan: Institute on Lake Superior Geology, Field Trip Guidebooks, v. 34, part 2, p. A1-A18.

Baxter, D.A., Bornhorst, T.J., and VanAlstine, J.C., 1987, Geology, structure, and associated precious metal mineralization of Archean rocks in vicinity of Clark Creek, Marquette County, Michigan: Michigan Geological Survey, Department of Natural Resources, Open-File Report OFR-87-8,54 p. and map (1:6000).

Johnson, R.C., Bornhorst, T.J., and VanAlstine, J., 1987, Geologic setting of precious metal mineralization in the Silver Creek to Island Lake area, Marquette County, Michigan: Michigan Geological Survey, Department of Natural Resources, Open-File Report, OFR-87-4, supersedes OFR-86-2, 134 p. and map (1:6000).

Bornhorst, T.J., Ruotsala, A.P., and Stadnik, P.M., 1987, Cobalt, nickel, and vanadium contents of pyrite concentrates from the Michigamme Formation, northern Michigan: Michigan Geological Survey, Department of Natural Resources, Open-File Report, OFR-87-6, 26 p.

Johnson, R.C., Bornhorst, T.J., and VanAlstine, J., 1986, Geology and precious metal mineralization of the Silver Creek to Rocking Chair Lakes area, Marquette County, Michigan: Michigan Geological Survey Department of Natural Resources, Open-File Report, OFR-86-2, 37 p. and map (1:6000).

Boben, C.L., Bornhorst, T.J., and VanAlstine, J., 1986, Detailed geological study of three precious metal prospects in Marquette County and one in Gogebic County, Michigan: Michigan Geological Survey, Department of Natural Resources, Open-File Report, OFR-86-1, 40 p. and 4 maps (1:6000 to 2400).

Owens, E. and Bornhorst, T.J., 1985, Geology of precious metal prospects north of the Dead River storage basin in Section 35, T49N, R27W, and north part of Section 2, T48N, R27W, Marquette County, Michigan: Michigan Geological Survey, Department of Natural Resources, Open-File Report, OFR-85-2, 105 p. and map and cross-section (1:2400).

Holm, D.M. and Bornhorst, T.J., 1978, Probes - October 1, 1977 to September 30, 1978: Los Alamos Scientific Laboratory Progress Report, LA-7796-PR, 5 p.

PUBLISHED ABSTRACTS ~120 total

RESEARCH ADVISEMENT

Chairperson (and Co-Chair) Completed: 27 M.S. Theses, 4 Ph.D. Dissertations.

Committee Member Completed (does not include those chaired): 50 M.S. Theses, 12 Ph.D. Dissertations (2 European Ph.D. committees)

"Senior undergraduate" Independent Research Projects Completed: 29