We will address the origin and evolution of igneous plutons and volcanic rocks in the St. Francois Mountains terrane. Our principal objectives are to fully characterize the whole-rock geochemistry (major, trace, and rare earth element) and radiogenic isotope (Sr, Nd, and Pb) signature of intrusive and volcanic rocks in the study area.
We will collect samples for analysis from outcrops and drill cores, and from previous collections of other workers (e.g., underground workings of mines). Analyses we will perform include:
major, trace, and rare earth element geochemistry or whole rocks by modern techniques, mainly via XRF (major elements) and ICP-MS (trace elements and rare earth elements); and
Sr, Nd, and Pb isotopes on whole rocks and mineral separates, done by thermal ionization mass spectometry.