Developing a Tephra Database for IODP Sites U1417 & U1418: Late Miocene to Present Evolution of Disruptive Volcanism along the Gulf of Alaska Margin (2014)
Submitted by Dr. Jeff apple Benowitz (UAF) and Jason Addison (USGS)
Abstract: This proposal seeks funding for a two year project to identify and develop a geochemical and geochronological database for tephras from IODP Sites U1417 & U1418 drilled in the Gulf of Alaska. A combination of data will be collected to determine: (i) tephra sources from the region’s three major volcanic provinces; (ii) the late Miocene-to-present evolution of eruptive volcanism along the Gulf of Alaska margin; and (iii) construct a marine tephra database for use in terrestrial paleoclimatic studies. Methods will include: microscope and magnetic susceptibility identification of tephra; grain-specific major and trace element geochemical fingerprinting; and 40Ar/39Ar radiometric dating of glass, hornblende, biotite, and/or sanidine. These results will be integrated with the paleomagnetic, stable 18O isotope, and microfossil chronostratigraphies of Sites U1417 & U1418, and with existing terrestrial Alaskan and Canadian Yukon tephra data.
Broader Impacts: Graduate research and science education will be a foundation of this project. The proposed study will provide new opportunities for a graduate student to learn and integrate a diverse suite of state-of-the-art laboratory skills and the opportunity for the student participant to present results at scientific meetings. The graduate student will gain additional experience as they collaborate directly with researchers at USGS. Results of this work will be disseminated in scientific journals, a USGS Fact Sheet for the general public, and data with sample information will be archived in digital databases. Analytical data will be made publicly available through established geoinformatic databases (e.g., NSF-funded EarthChem). The results from this proposed work will also be disseminated amongst the other IODP Expedition 341 participants (both shipboard and shore-based) to further ancillary expedition objectives.
Download proposal The project budget is not included in the download; please contact Dr. Benowitz for this information.
Why are young volcanic rocks undateable: chemistry, environment, or instrumentation?
Submitted by Dr. Jeff apple Benowitz (UAF)
Overview: This proposal seeks funding for a two-year fellowship to increase the research capacity of a young non- tenure track Research Faculty member, his research group, and the University of Alaska's Geochronology Facility (UAF-GF) through training and collaboration at the Oregon State University (Corvallis) Argon Geochronology Laboratory (OSU-AGL). OSU-AGL is considered one of the premier geochronology facilities in the world due to its advanced instrumentation, in-house software development, and renowned faculty who have assisted in furthering the dating limits of 40Ar/39Ar geochronology. The PI is an expert in operating a noble gas mass spectrometer by peak-hopping on a single detector, however he is motivated to expand his research aptitude in operating and maintaining a noble gas multi-collector mass spectrometer. This residence will prepare the PI for modernizing his inherited legacy lab and enable the PI to pursue his research interests in what limits the date-ability of young volcanic rocks.
Broader Impacts: This fellowship will provide further training for a young career scientist in multi-collector mass spectrometry and build PI and laboratory collaborations between the UAF and OSU. Graduate student STEM training will be provided. Results will be disseminated via peer-reviewed journals. Data will be archived in digital databases and made available through geoinformatic databases (e.g., Geochron). The PI will give lectures on high temperature thermochronology applications applied to Alaska tectonic problems during his residence in Corvallis in order to share knowledge and build collaborations.