HR: 09:00h
AN: GP41A-05 [Abstracts]
TI: PreliminaryEquatorial Paleomagnetic results from Mt Kenya lavas. Neil D Opdyke, 1, Dennis V Kent, 2, Kainian Huang ,1, J.P. Patel , 3
AU: * Opdyke, N D
EM: drno@ufl.edu
AF: Department of Earth Sciences
The University of Florida, Williamson Hall, Gainesville, Fl 32611, United States
AU: Kent, D V
EM: dvk@rci.rutgers.edu
AF: Department of Geological Sciences, Rutgers University, Picateway, NJ 08854-8065, United
States
AU: Huang, K
EM: knhuang@geology.ufl.edu
AF: Department of Earth Sciences
The University of Florida, Williamson Hall, Gainesville, Fl 32611, United States
AU: Patel, J P
EM: jayanti@uonbi.ac.ke
AF: Department of Physics, The University of Nairobi, Nairobi, 30197, Kenya
AB:
Field work on this study was carried out in August of 2006 by field parties from the University of Florida and
Rutgers University. Mt Kenya is believed to be Plio-Pleistocene in age and an Argon dating survey is underway
Ten samples were taken at each site consisting of one exposure in individual lava Flows. These exposures are
usually in road cuts, streambeds and in some cases roadbeds. We sampled 100 sites distributed around the Mt
Kenya Massif and to the northeast along the Nyambini range. The equator bisex's Mt Kenya
and all sites were sampled within 40" north or south of the equator . The samples were
returned to the US and processed at the University of Florida paleomagnetic laboratory. Many sites were severely
affected by lightning however after demagnetization 68 sites yielded directions with alpha
95's equal to or less than 10°. Normal magnetized sites dominate, with N=58
(Dec=1°,Inc -0.1°,α95=2.6°) whereas only 10 reverse
sites(Dec. =181.9,Inc. .6°α 95=8°) were identified. The combined site mean direction
is Dec=1.1°, Inc..= -0.2° and α 95=3.2°. This result is not significantly different
from what is expected from the geocentric axial dipole. VGP's were calculated from each
site and the dispersion is low with the ASD = 11° which is in agreement with model
"G" of MacFadden and McElhinny .No transitional directions were
identified . Quadrupole components are not resolved.
1 Department of geological Sciences, the University of Florida , 2 Dept of Geology, Rutgers University,3,dept of
Physics ,The University of Nairobi
DE: 1500 GEOMAGNETISM AND PALEOMAGNETISM
DE: 1560 Time variations: secular and longer
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2007 Fall Meeting