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.