Lead article, and cover in GSA Today, advertising the "Subduction Top to Bottom 2" publication project in the GSA journal GEOSPHERE (editors G. E. Bebout, D. W. Scholl, R. J. Stern, L. M. Wallace, and P. Agard; to see this Open Access article, click here)
GEOSPHERE "Subduction Top to Bottom 2" Themed Issue (in progress; click here)
October 2013 issue of ELEMENTS on "Nitrogen and its (biogeocosmo)chemical cycling"
(editors G. E. Bebout, M. L. Fogel, and P. Cartigny; see the cover of the issue here)
Recent review articles/book chapters:
Carbon cycling in subduction
zones: Record in HP/UHP metamorphic rocks, with work based in the Italian/French/Swiss Alps (collaborative
with S. Angiboust, IPGP, Paris; P. Agard, UniversitÚ
Pierre et Marie Curie, Paris; Marco Scambellluri and Laura Crispini,
[presentations at recent Fall AGU meetings; Goldschmidt Conference, 2013, 2018; GSA Annual Meeting, 2014; see Cook-Kollars et al., 2014, and Collins et al., 2015, both papers in Chemical Geology; Scambelluri et al., 2016, Earth and Planetary Science Letters; Jaeckel et al., 2018, GEOSPHERE; recent research by EES students Kaylee Kraft (M.S.) and Gabe Epstein (Ph.D.)]
Volatiles cycling in subduction zones — Example of the Hikurangi margin, New Zealand: Ongoing, NSF-funded research aims to elucidate the cycling of volatiles (C, N, noble gases) across the Hikurangi margin, North Island, NZ. This study involves collaborations with researchers at the GNS Science (New Zealand; Bruce Christenson), the University of Tokyo (Hirochika Sumino), and the University of Minnesota (Ikuko Wada). Subduction inputs at this margin are being evaluated based in part on analyses of the C and N concentrations and isotope compositions in the sediment section entering the Hikurangi trench, using samples recently recovered by IODP Expedition 375. Thermal models of the margin will be merged with thermodynamic calculations of devolatilization in the subducting lithosphere/sediment section and outputs will be evaluated through analyses of volcanic and forearc cold seep gases.
See the News Feature on the Deep Carbon Observatory website (click here)
Nitrogen Isotope (GeoBio)chemistry:
Incorporation of N during biotic/abiotic chemical alteration of seafloor basalts and basaltic glasses (collaborative with Neil Banerjee and Matthew Izawa, Western University, Ontario, and Eizo Nakamura and Katsura Kobayashi, IPM; presented at LPSC, 2011, 2014; AbSciCon, 2012, 2015; Open Access article in Astrobiology; click here)
Other recent research:
We analyzed C-N concentrations and isotopic compositions of sediment [and altered seafloor basalt] recovered on ODP Legs 185 and 205 [see Sadofsky and Bebout, 2004, G-cubed; Li and Bebout, 2005, JGR and ODP Leg 205 Scientific
Results), with the
goals of characterizing organic sources and diagenetic history and subduction
input fluxes in the Izu-Bonin-Mariana and Central American convergent
margins. We also have been working
on sediment C-N inputs into the Sunda-Java margin.
Locations for DSDP/ODP Sites 211, 261, 262, and 765 are shown on the
seafloor topographic map above (image above is from Smith and Sandwell
Global Seafloor Topography, NOAA and Scripps Institution of Oceanography). Our most recent shorebased-scientist involvement is for the 2018 drilling at the Hikurangi margin, New Zealand (IODP Expedition 375).
Records of biogeochemical cycling of N (and other elements) in altered volcanic glasses (collaborative with Katsura Kobayashi and Eizo Nakamura; current work by Ph.D. student Matthew Nikitczuk; initial Open Access article in Astrobiology; click here)
Most of the research described here is funded by the National Science Foundation — funding for the research at the Institute for Planetary Materials is provided by MEXT (Ministry of Education, Culture, Sports, Science and Technology) and Okayama University, Japan.