Download CIDER 2011 Research Discussion 1

CIDER 2011 Research
Discussion 1
MULTIDISCIPLINARY
• La/Yb spikes in Andes: Crustal thickness &
pluton ages in other orogenies. GeoRock
– La is incompatiable/Yb is marginally compatible
– See Planck & Langmuir, 93
• Global orogenic reconstructions (see
McQuarrie) for the Cenozoic-Mesozoic with
global strain-rate and stress maps. Plate
motion changes associated with mountain
building (UT & DSDP plate reconstructions).
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Role of downgoing slab in deformation in the over-riding plate.
– Sdrolias & Mueller 200? G3
– Along arc seismic anisotropy with shrinking and growing lateral trench width (Long & Silver,
2009(?))
– Can you use mountain belt behavior including geodetic constraints at subduction zones as an
inverse problem for rheology
– Temporal and spatial variation of rheology in deformation zones
– What is the upper plate response to changes in subduction/convergence rate. See Heuret &
Lallemand, 200? EPSL
– Cocos-Caribbean-NA plate TJ
– Reconstruct the surface plates from the tomography
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Compare volumes, areas, and kinematics
Predict gravity, viscosity, density from tomography
– What role does anelasticity play in subduction
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How to make continental lithosphere, how do continents grow, are they
growing(?). What is the continental lithosphere?
– Using seismics, xenoliths, (Rudnick & Fountain, 1995; Behn & Keleman, 200?)
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Volcanic gaps and slab geometry?
The effects of Triple junctions on orogens
Relationship between magmatism and Eurasian subduction beneath Tibetan
plateau.
Dynamic vs static support in orogens. Realistic geodynamic models including
mantle wedge geometry predicting orogens.
Does Moho character correlate with crustal age, or with last tectonic event, or last
magmatic event.
• What starts orogeny in continent-ocean
collision and why is orogeny delayed until well
after the start of subduction?
• Depth of seismic anisotropy as a marker of
strain accumulation.
• What properties can be used to identify the
asthenosphere? Mantle melt data can be used
to identify the depth of the lithosphere. What
do current anisotropy measurements tells us
about the lithosphere
• Exhumation rates due to climate versus
subduction to collision
Escarpment dynamics (Norway, Venezuela, Big
Sur)
How is continental crust subducted and how
much continental crust has been subducted?
Forearcs are almost all gone.
What controls subduction erosion?
Force balance in continent-continent collision
Force balance in orogeny
Force balance in the Laramide orogeny.
• What are the most useful observations to
constrain isostatic versus dynamic support.
The magnitude of dynamic topography. What
differentiates dynamic from isostatic
topography.