COLLABORATIVE RESEARCH: Modern Chronologic and Geochemical Techniques Applies to a Young Volcanic Field in an Active Continental Rift: Potrillo Volcanic Field, NM

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This project combines geochronologic, paleomagnetic and geochemical studies of this Potrillo Volcanic Field of southern New Mexico. This young (Ma) field is located within the active Rio Grande Rift and is composed of a series of maare and several hundred mafic flows. Geochronologic methods will include 40AR/39Ar, U-series disequilibria, and surface exposure (3He) dating. The age limits of these three methods overlap, thus allowing an excellent opportunity to develop a robust chronology for the field while also testing the internal consistency of each method. The series of flows preserve a large population of high fidelity records of the geomagnetic field. An intensive paleomagnetic sampling regime, in conjunction with the chronologic studies, will be used to identify and date high amplitude geomagnetic excursions of the Earth's magnetic field and to examine to axial dipole hypothesis, a tenet of paleomagnetism which assumes that the geomagnetic field averages to a geocentric axial dipole over time. These studies, combined with trace element and petrological characterization of the flows, will provide insight into the rates of physical and chemical evolution and the eruptive cyclicity within is very young field and serve as a paradigm for currently active explosive volcanism contributing atmospheric aerosols on a global basis.