4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4 From: Rita Economos <rita.economos@xxxxxxxxx> 4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4-4 Dear Volcanological community, We are soliciting applications for a Ph.D. student at Southern Methodist University in Dallas, Texas, to begin Fall of 2019, who will play a key role in an NSF-funded project on â??Sulfur Isotope Systematics and Oxygen Fugacity Evolution in the 1257 CE Samalas Magma Reservoir, Indonesiaâ?? (see project abstract below). The selected Ph.D. student will be based at SMU under the primary supervision of Dr. Rita Economos. Other project participants include Drs. Marc-Antoine Longpré and Shuo Ding at Queens College, City University of New York. The project will be conducted in close collaboration with Dr. Céline Vidal (University of Cambridge), IPGP (France) and CVGHM (Indonesia) and Adrian Fiege (AMNH). Current plans for the Ph.D. project will focus on SIMS data collection and interpretation of stable isotope ratios in multiple magmatic phases, particularly apatites, but the project includes several additional cutting-edge analytical opportunities depending on the interests of the student. Applicants should follow the procedures for application for Graduate Study at Southern Methodist University by January 15th, 2019. Contact Rita Economos for additional information at reconomos@xxxxxxx. *Project abstract:* Sulfur is the third most abundant volatile element in volcanic systems following water and CO2. Release of sulfur to the atmosphere during volcanic eruptions can perturb climate on a global scale and cause acid rain, resulting in significant environmental impact. The eruption of Mt. Samalas on Lombok Island, Indonesia, in 1257 CE generated the largest volcanic sulfur emission event of the last 2000 years. This event is coincident with a multi-year global cooling event around the beginning of the â??Little Ice Ageâ??. The central research question of this project is: how did this volcano build up so much eruptible sulfur? The scientist participants will test hypotheses of sulfur enrichment mechanisms by probing deep into sulfurâ??s properties and behavior within sulfides, apatites, and volcanic glasses (rapidly cooled melts) from pumice samples from this eruption. The project will utilize the most advanced analytical techniques to investigate sulfur chemistry, many of which were developed recently by participants on the research team. This project will yield new insights into the capability of magmatic systems beneath volcanoes to accumulate reservoirs of eruptible sulfur large enough to create significant global environmental impacts. The project exploits the complex geochemical behavior of sulfur to track its movement from the liquid phase (silicate melt) into solid (mineral) and gas phases in magmatic systems. Sulfur is a polyvalent element that can change its valence state from S2- to S6+ over a narrow redox range relevant for terrestrial magmatic systems. This makes sulfur an excellent tracer for changes in magma redox conditions that may have played a critical role in the transport, enrichment, and release of sulfur during the 1257 Mt. Samalas eruption. The involved magmatic processes (e.g., degassing) should lead to predictable fractionations of sulfur isotopes in glasses and minerals, which will further constrain the dynamics of sulfur build-up at Samalas. The valence states of sulfur in minerals and glasses will be determined via X-ray absorption near-edge structure (XANES) spectroscopy, whereas sulfur isotope ratios will be measured by secondary ionization mass spectrometry (SIMS). This dovetailing of redox and isotope studies is a powerful new approach to addressing sulfur-related science questions. This project will serve as a blueprint for future studies of other volcanic systems and will have implications for magmatic sulfide ore-forming processes and crustal magma evolution of interest to the broader earth science community. ============================================================== Volcano Listserv is a collaborative venture among Arizona State University (ASU), Portland State University (PSU), the Global Volcanism Program (GVP) of the Smithsonian Institution's National Museum of Natural History, and the International Association for Volcanology and Chemistry of the Earth's Interior (IAVCEI). ASU - http://www.asu.edu/ PSU - http://pdx.edu/ GVP - http://www.volcano.si.edu/ IAVCEI - http://www.iavcei.org/ To unsubscribe from the volcano list, send the message: signoff volcano to: listserv@xxxxxxx, or write to: volcano-request@xxxxxxx. To contribute to the volcano list, send your message to: volcano@xxxxxxx. Please do not send attachments. ============================================================== ------------------------------
