QUANTIFYING CRUSTAL THICKNESS AND PALEOELEVATION IN THE VARISCAN OROGEN: GEOCHEMICAL EVIDENCE FOR TWO SHORT-LIVED CRUSTAL THICKENING AND THINNING CYCLES
HILLENBRAND, Ian, U.S. Geological Survey, Denver Federal Center, Denver, CO 80225; Department of Geosciences, University of Massachusetts, Amherst, 627 N Pleasant St, Amherst, MA 01003-9354 and WILLIAMS, Michael L., Department of Geosciences, University of Massachusetts Amherst, 627 N Pleasant St, Amherst, MA 01003