Collaborative Research: Spatiotemporal Evolution of the Neogene Ignimbrite Flare-up in the Altiplano-Puna Volcanic Complex, Central Andes: Insights into the Development of Large

点击翻译按钮获取中文摘要

This collaborative project is supported by the Petrology and Geochemistry program (in Earth Sciences), the Americas Program (in the Office of International Science and Engineering), and the EPSCoR program. The central focus of the research will be to better define the timing, pattern, and volume of ignimbrite volcanism in the Altiplano-Puna Volcanic Complex (APVC) of the Central Andes to address fundamental, yet persistent, questions about how large magmatic systems develop and evolve. The investigators hope to understand if the magmatic activity that led to the formation of this volcanic complex was truly episodic or if this initial impression is a function of incomplete characterization of the chronology of explosive events. Also, if episodic, what was the frequency and size of successive eruptions and what was the spatial pattern of the eruption series. They will address these questions by establishing a stratigraphic and volcanological framework for the major part of the APVC in the Lipez region of SW Bolivia through field mapping, 40Ar/39Ar geochronology, and geochemical and paleomagnetic (NRM) correlation techniques. This record will be correlated into the adjacent parts of the APVC in Chile and Argentina where a more coherent framework exists. These data, combined with knowledge of the petrogenesis and evolution of the magmas, will form the critical baseline from which magma production and intrusion rates can be calculated. Integration of these data into a regional GIS will facilitate a quantitative spatiotemporal analysis.Broader impacts of this project include training of a Ph.D. student in a variety of ignimbrite correlation techniques and modern 40Ar/39Ar geochronology methods. Undergraduate students will be involved in paleomagnetic analytical work and fieldwork. The findings will be disseminated to K-12 educators, non-traditional students, and the general public through the VolcanoWorld web site (http://volcano.und.nodak.edu/vw.html) and synergistic activities. Scientific results will be disseminated in a timely fashion to professional peer-groups and should have societal impact in furthering our understanding of episodic activity in large, explosive volcanic systems that are of concern for hazard mitigation programs. The close collaboration with a Bolivian colleague and a student ensures training, data and knowledge transfer, and consolidation of international cooperative research. Collaboration with an Argentine colleague will aid the process of correlation across the international border.