HR: 1340h
AN: GP43A-0924    [Abstracts]
TI: New Paleomagnetic and Rock Magnetic Results from the Late-Cretaceous Kap Kane Volcanics, North Greenland Large Igneous Province
AU: * Hawkins, L K
EM: lisa.hawkins@gmail.com
AF: Department of Earth and Planetary Sciences and Institute of Geophysics and Planetary Geophysics, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, United States
AU: Crane, K
EM: Keely.Crane@earth.ox.ac.uk
AF: Department of Earth Sciences, University of Oxford, Earth Sciences Parks Road, Oxford, OX1 3PR, Oxford, OX1 3PR, United Kingdom
AU: Knudsen, M F
EM: Mads.Knudsen@earth.ox.ac.uk
AF: Department of Earth Sciences, University of Oxford, Earth Sciences Parks Road, Oxford, OX1 3PR, Oxford, OX1 3PR, United Kingdom
AU: Zhao, X
EM: xzhao@pmc.ucsc.edu
AF: Department of Earth and Planetary Sciences and Institute of Geophysics and Planetary Geophysics, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, United States
AU: Tegner, C
EM: christian.tegner@geo.au.dk
AF: Department of Earth Sciences University of Aarhus, Hoegh-Guldbergs Gade 2, Aarhus, DK-8000 Aa, Denmark
AU: Holm, P M
EM: paulmh@geol.ku.dk
AF: Department of Geography and Geology Geology Section University of Copenhagen, ุster Voldgade 10, Copenhagen, DK-1350, Denmark
AU: Mac Niocaill, C
EM: conallm@earth.ox.ac.uk
AF: Department of Earth Sciences, University of Oxford, Earth Sciences Parks Road, Oxford, OX1 3PR, Oxford, OX1 3PR, United Kingdom
AU: Stemmerik, L
EM: larss@geol.ku.dk
AF: Department of Geography and Geology Geology Section University of Copenhagen, ุster Voldgade 10, Copenhagen, DK-1350, Denmark
AB: We present new paleomagnetic and rock magnetic data from our ongoing study of the 60-90 Ma volcanics from Kap Kane, North Greenland Large Igneous Province (NGLIP). During our July 2006 fieldwork in North Greenland, we obtained more than 100 samples of various lithology, including thick, massive ignimbrites, volcaniclastic sediments, mafic lavas (basalt to latite), crater breccia, and rhyolites. The samples have been subjected to detailed alternating field and thermal demagnetization experiments to understand their magnetization history and screen out those significantly contaminated by lightning or other secondary magnetizations for paleointensity work (on going). Generally, the Kap Kane volcanics display multicomponent behavior with a fairly large amount of scatter. After removal of a low-temperature component that resembles recent field directions, a well-defined characteristic component remains in most samples. Both normal and reversed magnetizations are observed, which is expected as the rocks presumably formed within 60-90 Ma. Selected samples have also been subjected to a series of rock magnetic measurements that focused on determining the Curie temperature and hysteresis parameters of the magnetic carriers in the rocks. Measurements of the weak-field susceptibility vs. temperature suggest that magnetite is the dominant magnetic mineral. However, resistance to alternating field demagnetization and the magnetic hysteresis behavior indicate that a significant amount of hematite is present in several samples as well. Our interpretation of the data from this investigation is ongoing, but the preliminary results have bearings on the paleogeography of North Greenland, the tectonic history of NGLIP, as well as the variation in intensity of the magnetic field during the Cretaceous Normal Superchron.
DE: 1525 Paleomagnetism applied to tectonics: regional, global
DE: 1527 Paleomagnetism applied to geologic processes
DE: 1540 Rock and mineral magnetism
DE: 1599 General or miscellaneous
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2007 Fall Meeting