MRI: Acquisition of a Thermal Ionization Mass Spectrometer for Studies of the Formation and Evolution of the Solid Earth

Carnegie Institution Of Washington, Washington DC

Investigators

Abstract

Acquisition of a Thermal Ionization Mass Spectrometer for Studies of the Formation and Evolution of the Solid Earth Geologic processes operate on time scales much longer than human experience. The record of these processes is recorded in the chemical and isotopic composition of Earth materials. Naturally occurring radioactive elements provide the clocks that record the sequence of events that led to the modern Earth. The primary tool used to extract this information is the mass spectrometer. This award supports acquisition of a mass spectrometer for the Department of Terrestrial Magnetism (DTM) at Carnegie Institute of Science. The new instrument will measure rocks to understand the history and nature of the Earth. It will improve the programs at DTM and will be available for scientists and students to use. Visiting scientists and students often lead their own geology research programs in the U.S. and worldwide. The new instrument will further strengthen educational opportunities for training the next generation of Earth scientists. This grant will fund the purchase of a new thermal ionization mass spectrometer for the geochemistry group at DTM. DTM has a record, dating back to the 1950`s, of developing new techniques in isotope geology and geochronology and applying them to a number of topics of importance in the geosciences. The new mass spectrometer with high-gain faraday amplifiers will expand current capabilities, particularly allowing measurement of smaller sample sizes, and will also allow high-precision isotopic analysis of the decay products of short-lived radionuclides including 142Nd, 182W and 53Cr. These systems are providing a much clearer look at how the processes that accompanied planet formation established major characteristics of Earth that persist to the present day. The requested instrument will allow isolation of incompatible measurement techniques between the new and existing instruments so that each can produce the highest quality data possible. The new instrument also will continue and expand training of the next generation of isotope geochemists in cutting edge techniques that can be used to probe fundamental questions relating to Earth formation and evolution. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.