HR: 0830h
AN: H51D-1092    [PDF]
TI: Tectono-morphic scenarios for the Southern Alps of New Zealand.
AU: Braun, J
EM: jean.braun@anu.edu.au
AF: australian national university, Research School of Earth Sciences, Canberra, ACT 0200 Australia
AU: * Herman, F
EM: frederic.herman@anu.edu.au
AF: australian national university, Research School of Earth Sciences, Canberra, ACT 0200 Australia
AU: Dunlap, W J
EM: jim.dunlap@anu.edu.au
AF: australian national university, Research School of Earth Sciences, Canberra, ACT 0200 Australia
AB: Temperature-time histories of rocks can be used to constrain tectonic and/or geomorphic scenarios of tectonically active areas. However, this inference is not always straightforward and relies on several interdependent mechanisms such as heat conduction, horizontal and vertical heat advection, tectonic kinematics, transient topography, etc, that must be taken into account while interpreting thermochronological datasets. Using a 3D finite element code (Pecube) that solves the transient heat transfer equation with an evolving topography, one can define accurate Temperature-time histories to interpret thermochronological datasets. Proper inversion methods (Monte Carlo type, e.g. Neighborhood Algorithm) can in turn be used to constrain the tectono-morphic development of a tectonically active area. This approach is applied to the continental collision that occurs in the South Island in New Zealand. Existing thermochronological datasets (K-Ar in Biotite and Muscovite, Fission tracks in apatite and zircon) complemented by recent low-T termochronometer data ((U-Th)/He in apatite and zircon) are used to derive information on the tectono-morphic development of the orogen: changes in tectonic regime, apparition of relief, geometry of major oblique-thrust and influence of glaciations.
DE: 1824 Geomorphology (1625)
SC: Hydrology [H]
MN: 2003 Fall Meeting