Lecturer, Department of Geology, Bryn Mawr College, Bryn Mawr, PA, 2008-present
MIT-WHOI Joint Program, Cambridge and Woods Hole, Massachusetts, 2003-2009; Ph.D. in Geology and Geophysics, 2009, Area of Specialization: Igneous geochemistry
Dissertation title: Basalt Petrogenesis Beneath Slow- and Ultraslow-Spreading Arctic Mid-Ocean Ridges
Faculty advisors: K.W.W. Sims, F.A. Frey
University of New Mexico, Albuquerque, New Mexico, 2001-2003; M.S. in Earth and Planetary Sciences, 2003, Area of Specialization: Volcanology
Thesis title: Volatile recycling in the Central American Subduction zone: Insights from Nicaraguan gas chemistry and nitrogen isotope systematics
Faculty advisor: T.P. Fischer
Summer of Applied Geophysical Experience, IGPP/LANL, Field course based in Santa Fe, New Mexico, 2001
Smith College, Northampton, Massachusetts, 1997-2001; B.A. in Geology with highest honors, minor in Archaeology, 2001, Magna cum laude
National Defense Science and Engineering Graduate Fellow, 2001-2005
Mineralogical Society of America Undergraduate Award, 2001
Phi Beta Kappa, 2001
Lab Coordinator: Earth Systems and the Environment Labs, Bryn Mawr College, 2009-present
• Prepared lessons and taught lab sections for Geology 103
• Supervised Teaching Assistants for lab sections
• Organized and helped run overnight class field trip
Instructor: Senior Thesis Seminar, Bryn Mawr College, 2009-present
• Developed new seminar to mentor and assist students with their senior capstone projects, and to teach scientific writing to undergraduates
Lab Coordinator: Physical Geology Labs, Bryn Mawr College, 2008
• Prepared lessons and taught all lab sections for Geology 101
• Supervised Teaching Assistants for lab sections
• Organized and helped run class field trip to Valley Forge National Monument
• Taught two guest lectures for the lecture part of the class
Teaching Assistant: Introduction to Marine Geology and Geophysics, WHOI, Woods Hole, MA, 2007
• Helped faculty prepare and proofread class materials
• Designed and implemented website for class
• Led recitations for students outside of class lectures
Science Mentor: Falmouth Public Schools, Falmouth, MA, 2007
• Coached middle school students on projects for a science fair.
Teaching Assistant: Mineralogy and Petrology, Smith College, Northampton, MA, 2000-2001
• Assisted J. Brady, helped run two Mineralogy and Petrology labs per week.
• Held office hours, aided students with class material.
Substitute Teacher, East Brunswick Public Schools, East Brunswick, NJ, 2000-2001
• Served as a substitute teacher in the public school system.
America Reads! Tutor, Northampton Public Schools, Northampton, MA, 1998
• Led group activities for first through third grade children with reading difficulties.
• Worked one-on-one with individual children to assist with reading.
General Earth Science and Geology, Mineralogy, Petrology, Volcanology, High-Temperature Geochemistry and Thermodynamics, Radiogenic Isotope Geochemistry.
Teaching young people how to learn effectively. Assisting girls and young women in particular in pursuing their interests. Helping all students become excited about science, geoscience, and research.
Doctoral Research: Geology and Geophysics, Woods Hole Oceanographic Institution and Earth, Atmospheric, and Planetary Sciences Department, Massachusetts Institute of Technology, 2003-2009
Advisors: Ken W.W. Sims, Fred A. Frey
Committee Members: G. Gaetani, P. Kelemen, J. Lin, S. Humphris (Chair)
Thesis title: Basalt Petrogenesis Beneath Slow- and Ultraslow-Spreading Arctic Mid-Ocean Ridges
• This study examines uranium-series isotope systematics (238U-230Th, 230Th-226Ra, 235U-231Pa, and 210Pb-226Ra systems) in lavas from the ridges north of Iceland, with a sample suite encompassing glassy mafic quartz tholeiites from the Tjörnes Fracture Zone and Kolbeinsey, Mohns, Knipovich, and Gakkel Ridges.
• Results suggest that Kolbeinsey Ridge lavas formed by deep melting in a long, peridotitic mantle melting column capable of generating large 230Th excesses in melts, as well as the large degrees of melting and thick crust observed at Kolbeinsey. Lavas from the Mohns and Knipovich Ridges, on the other hand, may reflect the influence of heterogeneous source rocks.
• The ultraslow-spreading Gakkel Ridge is the slowest oceanic spreading center on Earth, and it is underlain by a short melting column beneath a thick, cool lithospheric cap; melting in this setting produces very low-degree melts with small 230Th to small 238U excesses. The Gakkel rocks are young and have very large 226Ra excesses, corroborating global observations that indicate mixing between shallow and deep melts is an important mechanism for melt generation at mid-ocean ridges.
• Piston-cylinder experiments on partitioning of U, Th, and other trace elements during melting of garnet pyroxenite at 2.5 GPa showed that DU/DTh ratios are controlled by clinopyroxene and garnet site radii, which depend on bulk and crystal composition. Although pyroxenite can generate large 238U-230Th disequilibria during melting, the deep solidii and high productivities of mafic lithologies during melting preclude pyroxenite-peridotite binary melt mixtures as the primary mechanism producing observed ocean island basalt trends (e.g. Hawaii).
Masters Research: Earth and Planetary Sciences Department, University of New Mexico, 2001-2003
Advisor: Tobias P. Fischer
Committee Members: Y. Asmerom, F. Goff
Thesis title: Volatile recycling in the Central American Subduction zone: Insights from Nicaraguan gas chemistry and nitrogen isotope systematics
• Examined the chemistry and N isotopes of volcanic and geothermal gases from the Nicaraguan volcanic front, and used those data to fingerprint sources contributing N2, He, and Ar to the volcanic emissions along the front.
• Results showed that Nicaraguan volcanic and geothermal volatile emissions register large contributions from a high-δ15N, high N2/He source and lesser inputs from a low-δ15N, lower N2/He source.
• Modeled these inputs using estimates for subducted sediment and mantle wedge reservoirs, respectively, and found a large sediment contribution across most of Nicaragua, in agreement with observations from lava chemistry.
• Mass balance input and output calculations for the subduction zone suggest the need for another source of high-δ15N nitrogen beneath Nicaragua, perhaps altered ocean crust.
Graduate Intern, EES-11, Los Alamos National Laboratory, 2002
Mentor: W. Scott Baldridge
• Participated in a research project to develop and build a real-time, broad-sensitivity radon detector for use in geologic monitoring.
• Helped conduct tests during production of the detector.
Undergraduate Senior Thesis Research: Geology Department, Smith College, 2000-2001
Advisor: John Brady
Thesis title: Geochemistry of komatiite rocks, Archean Woodburn Lake Group, Pipedream Lake area, Churchill Province, Canada
• Combined Re-Os isotope measurements from CIW internship with new major and trace element whole rock data for suite of Canadian komatiites. Conducted electron microscope EDS analyses of komatiite samples to identify phases and characterize the degree of metamorphism they had experienced as lower amphibolite facies.
• Synthesized whole rock and in situ data to evaluate degree of element mobility during post-depositional alteration. Concluded that despite some element mobility after komatiite emplacement, least altered (non-spinifex) samples produced Re-Os isochron that matched 2.7 Ga U-Pb zircon age for intercalating geologic units.
Research Intern, Department of Terrestrial Magnetism, Carnegie Institution of Washington, 2000
Mentor: Steve Shirey
• Measured Re-Os isotope systematics in komatiite rocks from the Woodburn Lake Group in Canada (see above for summary of results). Measured lowest 187Os/188Os ratio in any igneous sample (0.1098), establishing extremely-well-characterized slightly subchondritic initial ratio for 2.7 Ga model age.
• Learned clean lab, rock dissolution, spiking, and Re-Os isotope extraction techniques and the basics of N-TIMS analysis.
Research Intern, Geomicrobiology Group, Princeton University, 1999
Mentor: T.C. Onstatt
• Assisted the Geomicrobiology Group at Princeton during early development of their bioremediation program. Analyzed grain size, pore volume, and phases present in sediment core sections using SEM and EDS. Ran programs and input data for carbon-fluorescing bacteria concentrations in cores.
• Performed night shifts during field tracer test for Virginia test site, sampling wells and making electrode measurements to monitor bromide tracer injection.
Igneous geochemistry, mantle chemical structure and evolution, radiogenic and uranium-series isotopes, volcanology and volcanic hazards.
American Geophysical Union, Mineralogical Society of America, Geochemical Society, Geological Society of America, Sigma Xi, Phi Beta Kappa
Elkins, L.J., Sims, K.W.W., Prytulak, J., Blichert-Toft, J., Blusztajn, J., Fretzdorff, S., Reagan, M., Haase, K., Elliott, T., Humphris, S., Schilling, J.-G., in prep., Generation of 226Ra, 238U, and 230Th excesses in Arctic mid-ocean ridge basalts from the Kolbeinsey, Mohns, Knipovich, and Gakkel Ridges, for submission to Geology.
Elkins, L.J., Sims, K.W.W., Prytulak, J., Mattielli, N., Elliott, T., Blichert-Toft, J., Blusztajn, J., Devey, C., Mertz, D., Kelemen, P., Spiegelman, M., Murrell, M., Schilling, J.-G., in prep., Melt generation and magma transport rates beneath the slow-spreading Kolbeinsey Ridge determined from 238U, 230Th, and 231Pa excesses, for submission to Earth Planet. Sci. Lett.
Elkins, L.J., Gaetani, G.A., Sims., K.W.W., 2008, Partitioning of U and Th during garnet pyroxenite partial melting: Constraints on the source of alkaline ocean island basalts, Earth Planet. Sci. Lett., 265, 270-286.
Elkins, L.J., Fischer, T.P., Hilton, D.R., Sharp, Z.D., McKnight, S., Walker, J., 2006. Tracing nitrogen in volcanic and geothermal volatiles from the Nicaraguan volcanic front, Geochim. Cosmochim. Acta 70, 5215-5235.
Elkins, L.J., Sims, K.W.W., Prytulak, J., Mattielli, N., Elliott, T., Blichert-Toft, J., Devey, C., Fretzdorff, S., Mertz, D., Kelement, P., Murrell, M. Schilling, J.-G., Humphris, S., 2008, Insights into melting processes on slow-spreading ridges north of Iceland from U, Th, Ra, and Pa isotopes, IAVCEI 2008 General Assembly, 1c/1e P05.
Elkins, L.J., Sims, K.W.W., Prytulak, J., Mattielli, N., Elliott, T., Kelemen, P., Mertz, D., Devey, C., Blichert- Toft, J., Schilling, J.-G., 2007, Constraints on Melting Beneath the Slow-Spreading Kolbeinsey Ridge from 238U, 230Th, and 231Pa Excesses, EOS Trans. AGU, Fall Meeting Suppl., V21B-0607.
Elkins, L.J., Gaetani, G.A., Sims, K.W.W., 2006, Mineral/melt partitioning of U and Th during partial melting of garnet pyroxenite, Geochim. Cosmochim. Acta Goldschmidt Suppl., 70, (18) 159.
Elkins, L.J., Fischer, T.P., Hilton, D.R., Shaw, A.M., McKnight, S., Strauch, W., Sharp, Z., 2002. Sediment Underplating Beneath Central America: Insights From N-He, δ15N Systematics of Volatile Discharges in Nicaragua, EOS Trans. AGU, Fall Meeting Suppl., V21B-1209.
• Assisted K. Sims with funding proposal and additional funding requests to NSF for dissertation research on Kolbeinsey Ridge. Responsible for annual reports and final report for this grant.
• Applied for and received funding to attend the American Geophysical Union fall conference (2007) from two funding sources (MIT travel assistance fund, WHOI Academic Programs Office fund).
• Petitioned for and negotiated funding from the WHOI Academic Programs Office to attend the Goldschmidt geochemical conference (2006) despite the sudden discontinuation of an expected fund (MIT travel assistance fund) at a critical time.
• Requested and arranged funds to participate in a research expedition and cruise to the Tjörnes Fracture Zone on the RS Poseidon (C. Devey, chief scientist) in August, 2005.