Nelia Dunbar

Activity Report 2008

Published Papers (prepare as complete reference citations and attach abstracts not previously submitted)

Dunbar, N.W., McIntosh, W.C., and Esser, R.P., 2008, Physical setting and tephrochronology of the summit caldera ice record at Mount Moulton, West Antarctica: Geological Society of America Bulletin, v. 120, p. 796-812.

Harpel, C.J., Kyle, P.R., and Dunbar, N.W., 2008, Englacial tephrostratigraphy of Erebus volcano, Antarctica: Journal of Volcanology and Geothermal Research, v. 177, p. 549-568.

Kelly, P.J., Dunbar, N.W., Kyle, P.R., and McIntosh, W.C., 2008, Refinement of the late Quaternary geologic history of Erebus volcano, Antarctica using Ar-40/Ar-39 and Cl-36 age determinations: Journal of Volcanology and Geothermal Research, v. 177, p. 569-577.

Kelly, P.J., Kyle, P.R., Dunbar, N.W., and Sims, K.W.W., 2008, Geochemistry and mineralogy of the phonolite lava lake, Erebus volcano, Antarctica: 1972-2004 and comparison with older lavas: Journal of Volcanology and Geothermal Research, v. 177, p. 589-605.

Quade, J., Levin, N., Simpson, S., Butler, R., McIntosh, W.C., Semaw, S., Kleinsasser, L., Dupont-Nivet, G., Renne, P., and Dunbar, N., 2008, The geology of Gona, Afar, Ethiopia: Geological Society of America Special Paper, v. 446, p. 1-31.

Geologic Maps (OF-GMs and GMs)

Books (written or edited)

Papers Presented at Professional Meetings (including abstracts; cite as complete references and attach abstract)

Bosket, M.E., Wilch, T.I., Panter, K.S., Dunbar, N.W., and McIntosh, W.C., 2008, Explosively Erupted Hydrovolcanic Deposits at Minna Saddle, Antarctica: Evidence of Limited Ice-Magma Interaction Geological Society of America Abstract Volume- Annual Meeting, p. 157-3.

Crow, R., Karlstrom, K.E., McIntosh, W., Peters, L., and Dunbar, N., 2008, History of Quaternary volcanism and lava dams in western Grand Canyon based on lidar analysis, Ar-40/Ar-39 dating, and field studies: Implications for flow stratigraphy, timing of volcanic events, and lava dams: Geosphere, v. 4, p. 183-206.

Dunbar, N.W., McIntosh, W.C., and Kurbatov, A.V., 2008, Integrated tephrochronology of the West Antarctic region - Implications for a potential tephra record in the West Antarctic Ice Sheet (WAIS) divide ice core: Geochemica cosmochimica acta, v. 72 (supplement- abstract volume), p. A232-A232.

Dunbar, N.W., Panter, K.S., Scanlan, M.K., Fargo, A.F., McIntosh, W.C., and Wilch, T.I., 2008, Evidence for Complex Mixing Processes Controlling the Composition of a Wide Range of Alkaline Volcanic Rocks at Minna Bluff, Antarctica.: Eos Trans. AGU, 89(53), Fall Meet. Suppl., p. V13C-2128.

Fargo, A., McIntosh, W., and Dunbar, N.W., 2008, ⁴⁰Ar/³⁹Ar Geochronology of Minna Bluff, Antarctica: Timing of Mid-Miocene Glacial Erosional Events Within the Ross Embayment: Eos Trans. AGU, 89(53), Fall Meet. Suppl., , p. V13C-2127.

Fargo, A.F., McIntosh, W.C., and Dunbar, N.W., 2008, ⁴⁰Ar/ ³⁹Ar geochronological analysis of Minna Bluff, Antarctica; evidence for past glacial events within the Antarctic cryosphere, New Mexico Geological Society spring meeting, Volume 30, New Mexico Bureau of Geology and Mineral Resources, p. 64.

Koning, D.J., Connell, S.D., Slate, J.L., Wan, E., Ferguson, J.F., Grauch, V.J.S., Woldegabriel, G., Peters, L., McIntosh, W., Dunbar, N., Broxton, D., and Baldridge, W.S., 2008, Structural control on the eastern Espanola Basin, Rio Grande Rift, north-central New Mexico: New Mexico Geology, v. 30, p. 54.

Ross, J.I., McIntosh, W.C., and Dunbar, N.W., 2008, ⁴⁰Ar/³⁹Ar chronology of volcanic events in the AND-1B drillcore - implications for age models and glacial history of the Ross Embayment: Eos Trans. AGU, 89(53), Fall Meet. Suppl., , p. C21B-0540.

Scanlan, M., Panter, K., Wilch, T.I., Dunbar, N.W., and McIntosh, W.C., 2008, Petrology of Inclusion-Rich Lavas at Minna Bluff, Antarctica: Implications for Magma Origin, Differentiation and Eruption Dynamics: Eos Trans. AGU, 89(53), Fall Meet. Suppl., p. V13C-2129.

Sims, K.W., Pichat, S., Reagan, M., Dunbar, N.W., Kyle, P., Gauthier, P., and Blichert-Toft, J., 2008, Do ²²⁶Ra-²³⁰Th isochrons provide realistic crystallization ages?: Eos Trans. AGU, 89(53), Fall Meet. Suppl., p. V11D-02.

Wilch, T.I., McIntosh, W.C., Panter, K.S., Dunbar, N.W., Smellie, J.L., Fargo, A., Scanlan, M., Zimmerer, M.J., Ross, J., and Bosket, M.E., 2008, Volcanic and Glacial Geology of the Miocene Minna Bluff Volcanic Complex, Antarctica: Eos Trans. AGU, 89(53), Fall Meet. Suppl., p. V11F-06.

Zimmerer, M.J., McIntosh, W., and Dunbar, N.W., 2008, A ⁴⁰Ar/³⁹Ar Geochronology and Thermochronology Study of Caldera Volcanism and Related Plutonic Processes, Questa Caldera, Northern New Mexico: Eos Trans. AGU, 89(53), Fall Meet. Suppl., p. V12A-05.

Reports and Miscellaneous Publications (Unpublished reports; include reports of contract research; open-file reports etc.)

Donahue, K., Dunbar, N.W., Heizler, L., McLemore, V., and Campbell, A., 2008, Characterization of the clay mineralogy within the rock piles on the Molycorp Questa mine site, Decision and Reliability Analysis reports prepared for Chevron Mining Inc. Questa, New Mexico, p. 9.

Donahue, K.M., Dunbar, N.W., Heizler, L., and McLemore, V.T., 2008, Origins of clay minerals in the Molycorp Mine Goathill North rock pile, unpublished report to Molycorp.

Dunbar, N.W., Heizler, L., and Sweeney, D., 2008, Mineralogical characterization of Questa rock-pile samples by petrographic and electron microprobe analysis, Decision and Reliability Analysis reports prepared for Chevron Mining Inc. Questa, New Mexico, p. 19.

McLemore, V., Heizler, L., and Dunbar, N.W., 2008, Humidity cell mineralogy and characterization, Decision and Reliability Analysis reports prepared for Chevron Mining Inc. Questa, New Mexico, p. 35.

McLemore, V.T., Ayakwah, G., Boakye, K., Campbell, A., Donahue, K., Dunbar, N., Gutierrez, L., Heizler, L., Lynn, R., Lueth, V., Osantowski, E., Phillips, E., Shannon, H., Smith, M., Tachie-Menson, S., van Dam, R., Viterbo, V.C., Walsh, P., and Wilson, G.W., 2008, Characterization of Goathill North Rock Pile, revised unpublished report to Molycorp.

McLemore, V.T., Donahue, K., Dunbar, N., and Heizler, L., 2008, Characterization of physical and chemical weathering in the rock piles and evaluation of weathering indices for the Questa rock piles, unpublished report to Chevron.

McLemore, V.T., Heizler, L., Dunbar, N., Phillips, E., Donahue, K., Sweeney, D., Dickens, A., and Ennin, F., 2008, Petrographic Analysis of Humidity Cell Samples, unpublished report to Chevron.

McLemore, V.T., Sweeney, D., Dunbar, N.W., Heizler, L., Campbell, A., and Phillips, E., 2008, Determining quantitative mineralogy using a modified MODAN approach (combination of petrographic techniques, whole rock chemistry, and MODAN), Decision and Reliability Analysis reports prepared for Chevron Mining Inc. Questa, New Mexico.

Sweeney, D., Dunbar, N.W., Logston, M., McLemore, V., Heizler, L., and Dickens, A., 2008, Boulder Study, Decision and Reliability Analysis reports prepared for Chevron Mining Inc. Questa, New Mexico, p. 27.

Journals Edited

Seminars and/or Speaking Engagements

-Co-lead Seismological Society of America field trip in Socorro area, April 19, 2008

-Presented talk for Albuquerque Gem and Mineral Club (April 28, 2008)

-Presented talk for Deming Geological Society (August 28, 2008)

Research Contracts and Grants Awarded (only title, not amounts to be posted on internet)

Research Contracts and Grants Proposed

Advancing the ⁴⁰Ar/³⁹Ar Geochronology of Ross Island and McMurdo Sound volcanism. Submitted to NSF

Awards and Other Recognitions

Featured in “New Mexico Woman” magazine

Service on Graduate Student Committees (list student and title of project and if you are major supervisor)

Committee member for Andrew Fargo (MS). Minna Bluff Geochronology

Committee member for Russell White (MS). Trench sediment characterization and cementation

Committee member for Jake Ross (MS). Chronology of the ANDRILL core

Committee member for Melissa Dimeo (MS). Pietown Dikes.

Committee member for Matt Zimmerer (MS). Chronology and geochemistry of the Latir Volcanic field

Committee member for Shasta Marrero (PhD). Cosmogenic investigations as part of CHRONOS project.

Committee member for Lara Owens (PhD). Geothermal investigations

Committee member for Bess Koffman (PhD). Investigation of Fe particulates in the WAIS Divide ice core.

Courses Taught

Theory and Practice of Electron Microprobe Analysis (GEOC 589). Fall 2008

Assisted in A. Campbell’s “Experimental Mineralogy” and “Stable Isotope” classes

Continuing Education Courses Given/Taken

Service on Institute Committees

Service in Professional Societies (it is your choice whether you wish to include this information on internet site)

Member of American Geophysical Union

Member of the Mineralogical Society of America

Member of Microbeam Analysis Society

Member of New Mexico Microbeam Users Group

Service on Commissions/Councils/Boards

Member of Antarctic Glaciology Data Center advisory board

Bureau Service Projects Active This Period

-Member of building committee

-Associate Director for laboratories

-Maintenance of Electron Microprobe and Carrizozo Malpais Web site http://geoinfo.nmt.edu/staff/dunbar/carrizozo/carrizozo.html

-Bureau Equipment Committee member

-Member of the Geological Editorial Board for Lite Geology

-Assisting numerous Bureau researchers and students with sample preparation for, and collection and presentation of electron microprobe and scanning electron microscope analyses.

-Providing tours of the electron microprobe facility for New Mexico Tech alumni, New Mexico Tech classes, and visiting educational groups.

-Answering various phone calls and other inquiries about volcanoes, earthquakes, and other aspects of New Mexico geology.

-Provided letters of support and information for Bureau proposals, particularly relative to electron microprobe laboratory.

Research Projects Active This Period

*Investigation of the long-term stability of waste rock piles at the Molycorps/Questa Mine

*Tephrochronology, chemical fingerprinting, and correlation of tephra layers in ancestral Rio Grande sediments. (in conjunction with D. Love, S. Connell, S. Cather, W. McIntosh, and others)

*Cosmogenic exposure dating of young basalts in New Mexico

*Englacial tephrochronology of blue ice areas of Antarctica: Implication to ice sheet history and ice-bound climate records.

*Tephrochronology of the Siple and Taylor Dome Ice Cores.

*Tephrochronology of the South Pole SPRESSO Core.

*Tephrochronology of the WAIS Divide Core.

*Tephrochronology of the ANDRILL Core.

*Investigation of the volcanic geology of Minna Bluff, Antarctica

* Detrital monazite geochronology of Ortega quartzite clasts in Pennsylvanian strata of the Northern Truchas uplift, Northern New Mexico: implications for the slip history of the Picuris-Pecos fault

Public Service/Education and Outreach

-Participated in E&ES graduate student recruitment weekend (mid March). Gave several lab tours as part of visit.

-Co-lead field trip for the IRIS group of summer intern students. (May 29, 2008)

-Hosted and instructed undergraduate students from Albion College and Fort Lewis college in the microprobe laboratory (spring 2009).

-Co-lead field trip to Los Lunas Volcano for Los Lunas summer education program (June 23, 2008)

-Provided interview for El Defensor Chieftan article (Sept 11, 2008)

-Provided interview for KNME-TV program “Why I became a scientist” (Sept 22, 2008)

-Assisting numerous non-Bureau researchers and students with sample preparation for, and collection and presentation of electron microprobe and scanning electron microscope analyses. Also, assisted researchers at other institutions with electron microprobe questions.

-Provided tours of the electron microprobe facility for New Mexico Tech alumni, New Mexico Tech classes, visiting prospective students, and other educational groups.

-Answering various phone calls and other inquiries about volcanoes, earthquakes, and other aspects of New Mexico geology.

-Giving talks about geology to school groups.

-Adjunct Appointment to E&ES Department

-Provided letters of support and information for non-Bureau proposals, particularly relative to electron microprobe laboratory.

Papers and Proposals Reviewed

Reviewed a number of papers and proposals for peer-reviewed journals and NSF.

Other Accomplishments