Forrest Horton
Associate Scientist
Department of Geology & Geophysics
Woods Hole Oceanographic Institution
Carbonatite Magmatism
Carbonatites are rare igneous rocks that consist of >50% carbonate minerals. Unstable in the upper crust, primary igneous carbonatites are thought to derive from Earth's mantle and thus hold precious clues about the deep carbon cycle. I study the isotopic composition of these rocks to better understand their mantle origins and to investigate the processes by which carbon travels through Earth's lithosphere.
I am currently investigating the Khanneshin carbonatite volcano in Afghanistan, a solitary volcanic feature in the Registan Desert (see photo above taken from a helicopter). Samples I helped collect from this volcano will provide geochemical insight about carbon systematics in the underlying mantle. These rocks are also potentially an important economic resource of rare earth elements that have many high-tech applications. See the following publication for more information about the Khanneshin volcano:
Tucker, R.D., Belkin, H.E., Schulz, K.J., Peters, S.G., Horton, F., Buttleman, K., Scott, E.R., 2012, A major rare-earth element (LREE) resource in the Khanneshin carbonatite complex, Southern Afghanistan: Economic Geology, v. 107, p. 197–208.