Geologic mapping, economic geology, and applications of geochemistry and geophysics to geologic interpretation
Education and/or Training
M.S. in Geology, University of Alaska Fairbanks, 2007
B.A. in Geology, Middlebury College, Vermont, 2004
Projects and/or Research Interests
I participate in bedrock geologic mapping projects for the purpose of understanding Alaska's metallic mineral resources. My focus is on the generation and integrative interpretation of geologic, geophysical, and geochemical data to understand the formation of mineral deposits in space and time.
My current role is to lead the DGGS's Wrangellia project, a multiyear geological assessment of the potential of central Alaska to host economic deposits of the Strategic and Critical platinum-group elements. This project encompasses new geologic mapping, geochemistry, geochronology, and historic data compilation with the objective of accurately establishing the extents and geological framework of the Late Triassic Wrangellia metallogenic province in Alaska.
My background as an Alaska-based exploration geologist has given me broad experience with mapping and geologic interpretation in a variety of geologic terranes and mineral deposit types throughout the state.
Professional Experience
2013-present: Geologist, Mineral Resources, State of Alaska Division of Geological & Geophysical Surveys. Wrangellia platinum-group element-related mapping and research project, Talkeetna Mountains, Alaska.
2010-2012: Exploration Geologist, NovaGold Resources and NovaCopper Inc. Bornite sediment-hosted copper and Arctic volcanogenic massive sulfide projects, southwestern Brooks Range, Alaska.
2009: Senior Geologist, Northern Associates. Livengood intrusion-related gold project, Interior Alaska
2005-2008: Project Geologist, NovaGold Resources. Arctic volcanogenic massive sulfide, southwestern Brooks Range, Alaska; Nome, Alaska orogenic gold exploration; Galore Creek copper-gold porphyry project, northwestern British Columbia.
2004: Junior Geologist: Avalon Development Corp. Regional copper porphyry exploration, Iliamna, Alaska.
2003: Geology Intern, Kennecott Greens Creek Mining Company. Greens Creek volcanogenic massive sulfide mine, Juneau, Alaska.
Selected Professional Activities
2015-2016: Affiliate Faculty, University of Alaska Fairbanks Department of Geoscience
USGS EDMAP Program Mentor
Member, Society of Economic Geologists
Member, Geological Society of America
Selected Publications
- Freeman, L.K., Newberry, R.J., Griesel, G.A., Elliott, B.A., Lough, T.A., and Twelker, Evan, 2022, Bedrock geologic map of the eastern Moran area, Tanana B-6 and C-6 quadrangles, Alaska: Alaska Division of Geological & Geophysical Surveys Raw Data File 2022-11, 16 p. https://doi.org/10.14509/30884
- Twelker, Evan, ed., 2021, Geologic investigation of the Ladue River-Mount Fairplay area, eastern Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2021-5, 86 p. https://doi.org/10.14509/30734
- Twelker, Evan, Newberry, R.J., Wypych, Alicja, Naibert, T.J., Wildland, A.D., Sicard, K.R., Regan, S.P., Athey, J.E., Wyatt, W.C., and Lopez, J.A., 2021, Bedrock geologic map of the Ladue River-Mount Fairplay area, Tanacross and Nabesna quadrangles, Alaska, in Twelker, Evan, ed., Geologic investigation of the Ladue River-Mount Fairplay area, eastern Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2021-5A, p. 1-32, 1 sheet, scale 1:100,000. https://doi.org/10.14509/30735
- Newberry, R.J., and Twelker, Evan, 2021, Metamorphism of the Ladue River-Mount Fairplay area, in Twelker, Evan, ed., Geologic investigation of the Ladue River-Mount Fairplay area, eastern Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2021-5B, p. 33-39. https://doi.org/10.14509/30736
- Twelker, Evan, and O'Sullivan, P.B., 2021, U-Pb detrital zircon geochronology of Cretaceous-Cenozoic sedimentary rocks in the Ladue River-Mount Fairplay area, Alaska: Alaska Division of Geological & Geophysical Surveys Preliminary Interpretive Report 2021-2, 16 p. https://doi.org/10.14509/30683
- Twelker, Evan, Wildland, A.D., Werdon, M.B., Sicard, K.R., Wypych, Alicja, Naibert, T.J., Athey, J.E., Willingham, A.L., and Lockett, A.C., 2021, Preliminary bedrock geologic map database, northeastern Richardson mining district, Alaska: Alaska Division of Geological & Geophysical Surveys Raw Data File 2021-9, 4 p. https://doi.org/10.14509/30676
- Twelker, Evan, Lande, L.L., Newberry, R.J., Wypych, Alicja, Sicard, K.R., and Freeman, L.K., 2020, Magmatic and structural framework of PGE and other mineralization in northwestern Wrangellia, central Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2020-6, 72 p. https://doi.org/10.14509/30468
- Twelker, Evan, Newberry, R.J., Wypych, Alicja, Sicard, K.R., and Naibert, T.J., 2020, Mineral occurrences in the Tok River area, eastern Alaska Range: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2020-8, 49 p. https://doi.org/10.14509/30471
- Twelker, Evan, Wypych, Alicja, Sicard, K.R., Naibert, T.J., Werdon, M.B., Athey, J.E., Willingham, A.L., and Lockett, A.C., 2017, Major-oxide and trace-element geochemical data from rocks collected in the Richardson mining district, Big Delta Quadrangle, Alaska: Alaska Division of Geological & Geophysical Surveys Raw Data File 2017-11, 4 p. https://doi.org/10.14509/29779
- Twelker, Evan, and O'Sullivan, P.B., 2016, U-Pb zircon age data from meta-igneous rocks in the Clearwater Mountains, Mount Hayes A-6 Quadrangle, Alaska: Alaska Division of Geological & Geophysical Surveys Raw Data File 2016-8, 17 p. https://doi.org/10.14509/29663
- Twelker, Evan, Freeman, L.K., Sicard, K.R., and Busk, A.C., 2016, Preliminary report on mineral occurrences in the Tok River area, Alaska: Alaska Division of Geological & Geophysical Surveys Preliminary Interpretive Report 2016-2, 7 p. https://doi.org/10.14509/29605
- Twelker, Evan, Hubbard, T.D., Wypych, Alicja, Sicard, K.R., Newberry, R.J., Reioux, D.A., Freeman, L.K., and Lande, L.L., 2015, Geologic map of the Talkeetna Mountains C-4 Quadrangle and adjoining areas, central Alaska: Alaska Division of Geological & Geophysical Surveys Preliminary Interpretive Report 2015-6, 16 p., 1 sheet, scale 1:50,000. https://doi.org/10.14509/29470
- Twelker, Evan, 2007, A breccia-centered ore and alteration model for the Copper Canyon alkalic Cu-Au porphyry deposit, British Columbia: University of Alaska Fairbanks, M.S. thesis, xii, 141 p., illust., maps.
Selected Presentations
- Twelker, Evan, Emond, A.M., Newberry, R.J., Naibert, T.J., Gavel, M.M., and Buchanan, J.W., 2023, DGGS Earth MRI geologic mapping and geophysics program update (presentation): Alaska Miners Association annual convention, Anchorage, Alaska, November 7, 2023: Alaska Division of Geological & Geophysical Surveys, 24 p. https://doi.org/10.14509/31099
- Werdon, M.B., and Twelker, Evan, 2022, 2021 Alaska mining industry update (presentation): Association for Mineral Exploration Roundup, January 31, 2022: Alaska Division of Geological & Geophysical Surveys, 38 p. https://doi.org/10.14509/30852
- Twelker, Evan, Wypych, Alicja, Sicard, K.R., Naibert, T.J., Athey, J.E., Wyatt, W.C., Newberry, R.J., Regan, S.P., Wildland, A.D., and Lopez, J.A., 2019, Draft (as of 11/5/2019) geologic map of the eastern Tanacross area (poster); Alaska Miners Association Annual Convention, Anchorage, Alaska, November 5-7, 2019: Alaska Division of Geological & Geophysical Surveys, 4 p. https://doi.org/10.14509/30414
- Twelker, Evan, Newberry, R.J., Wypych, Alicja, Sicard, K.R., and Naibert, T.J., 2018, DGGS investigations of gold prospects in the Tok River area, eastern Alaska (presentation): Alaska Miners Association 26th Biennial Convention, Fairbanks, Alaska March 26-31, 2018: Alaska Division of Geological & Geophysical Surveys, 31 p. https://doi.org/10.14509/30030
- Twelker, Evan, Werdon, M.B., Sicard, K.R., Wypych, Alicja, Naibert, T.J., Athey, J.E., Willingham, A.L., and Lockett, A.C., 2017, Geologic mapping in the Richardson-Uncle Sam area, interior Alaska (presentation): Alaska Miners Association Annual Convention, Anchorage, Alaska, November 7-12, 2017: Alaska Division of Geological & Geophysical Surveys, 37 p. https://doi.org/10.14509/29811
- Twelker, Evan, and Lande, Lauren, 2015, DGGS geological investigations in western Wrangellia (presentation): Alaska Miners Association Annual Convention, Anchorage, Alaska, November 1-5, 2015: Alaska Division of Geological & Geophysical Surveys, 45 p. https://doi.org/10.14509/29531
- Twelker, Evan, Newberry, R.J., Wypych, Alicja, Sicard, K.R., Reioux, D.A., Freeman, L.K., Lande, L.L., Blodgett, R.B., and Benowitz, J.A., 2015, New geologic mapping in western Wrangellia, Talkeetna Mountains, Alaska (poster): Geological Society of America Cordilleran Section Meeting, Anchorage, Alaska, 11-13 May, 2015.
- Twelker, Evan, Wypych, Alicja, Sicard, K.R., Newberry, R.J., Freeman, L.K., Reioux, D.A., and Lande, Lauren, 2014, Preliminary results from 2014 geologic mapping in the Talkeetna Mountains, Alaska (presentation): Alaska Miners Association Annual Convention, Anchorage, Alaska, November 3-9, 2014: Alaska Division of Geological & Geophysical Surveys, 28 p. https://doi.org/10.14509/29160
- Twelker, Evan, Wypych, Alicja, and Newberry, R.J., 2014, New data and insight on the Late Triassic Wrangellia magmatic Ni-Cu-Co-PGE system in the Talkeetna Mountains, central Alaska (poster): Society of Economic Geologists 2014 Conference, September 27-30, 2014: Alaska Division of Geological & Geophysical Surveys, 1 sheet. https://doi.org/10.14509/29139
- Twelker, Evan, and Burns, L.E., 2014, New geochemical and geophysical data from the western Wrangellia minerals assessment area (presentation): Alaska Miners Association 24th Biennial Mining Conference, Fairbanks, Alaska April 7-13, 2014: Alaska Division of Geological & Geophysical Surveys, 34 p. https://doi.org/10.14509/27284
- Twelker, Evan, Newberry, R.J., Freeman, L.K., Sicard, K.R., Reioux, D.A., and Bachmann, E.N., 2013, DGGS geologic and mineral-resource assessment of the western Wrangellia terrane, central Alaska: Initial progress report (presentation): Alaska Miners Association Annual Convention, Anchorage, Alaska, November 4-10, 2013: Alaska Division of Geological & Geophysical Surveys, 25 p. https://doi.org/10.14509/26821
