Magnetic Properties and Differentiation of the Antarctic Crust: Constraints From a Rock Magnetic Database

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9909712GrunowThis award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports development of an Antarctic rock-magnetic database. The Antarctic Digital Magnetic Anomaly Project's (ADMAP) goal of creating an Antarctic digital magnetic database will help evaluate the sub-ice bedrock geology of Antarctica. An integral part of the ADMAP program is to assemble the rock physical property data from the few but very important bedrock exposures in Antarctica. These outcrops represent the only ground truth for geophysical surveys. The goals of this project are to evaluate published and unpublished rock magnetic site data from Antarctica and enter this information into a database. Presently, at least 10,000 paleomagnetic drill core samples, representing more than 1000 sites have been obtained in Archean to Cenozoic Antarctic rocks. Such a collection represents a unique source of rock physical property data. The database developed by this project would include rock type, site location, NRM, susceptibility, anisotropy, declination/inclination, VGP, rock age, likely magnetic carrier, regional structural information data, and other related data. Compiling these rock physical property data sites would be useful for future interpretations of geophysical and paleoclimate data by addressing questions related to:1) The demarcation of potential crustal boundaries in both East and West Antarctica (are there terrane boundaries in West Antarctica?, are crustal suture zones present in East Antarctica?, etc),2) The extent of the Cambro-Ordovician magmatic arc in the Transantarctic Mountains,3) The geometry and extent of Jurassic Ferrar Group magmatic rocks,4) The extent of Cenozoic volcanic rocks, and5) Provenance analyses for paleoclimate research.The database will be accessible on the Internet. The general format will be based on the new US Antarctic Geologic Database (AGD) but modified to include the rock magnetic information. The server for the AGD is located at the Byrd Polar Research Center and can accommodate the Antarctic rock magnetic database (ARMD) as well. Individual investigators will be able to enter new rock magnetic data in the future. The ARMD will be linked to existing paleomagnetic and Antarctic databases.