Geology, Petrology and Geodynamics: Peter Kelemen & Colleagues
The Geology, Petrology and Geodynamics Group at LDEO involves Prof. Peter Kelemen and his students and colleagues. We investigate a variety of interactions between physical and chemical processes in the solid earth, with a focus on reactive transport of melt and fluid, and on feedback mechanisms that lead to unstable behavior.
Current areas of active research include
(1) study of fluid-rock reactions that create carbonate minerals from dissolved CO2, in part in order to learn from natural processes in order to design enhanced, in situ mineral carbonation techniques for large scale geological CO2 capture and storage, (recent papers by Kelemen & Matter, Proc Nat Acad Sci 2008; Matter & Kelemen, Nature Geosci 2009; Rudge et al., Earth Planet. Sci. Lett. 2010).
(2) study of shear zones in the upper mantle that may play a key role in plate tectonics, and may undergo non-steady creep that produces "viscous earthquakes" at depths of 50 to 200 km or more and/or provides a hitherto overlooked forcing for shallower earthquakes (recent papers by Kelemen & Hirth, Nature 2007; Homburg et al., Geology 2010).
(3) study of recycling of elements from subducting sediments into arc magmas and the mantle, from the perspective of "Utra-High Pressure" metasedimentary rocks that were subducted to 150 km depth or more, and should represent the residues of this recycling process (papers in prep. by Behn et al. 2010, Hacker et al. 2010).
Our past work (and ongoing interests!) also include reactive melt transport in the mantle processes of igneous accretion of oceanic lower crust and arc lower crust, gravitational instability and "delamination" of dense lower crustal lithologies, arc magmatism and its role in formation of continental crust, and processes of formation of cratonic upper mantle - the nucleii of the continents - in the Archean Earth.