MICRO-PIXE ANALYSIS OF CARBONATES AND SILICATES - TRACKING FLUID-FLOWIN CRUSTAL ENVIRONMENTS

Proton-induced X-ray (PIXE) analyses on a micro-scale of trace-element (TE) variations in metamorphic and hydrothermal minerals can provide insights into fluid-flow processes in lithospheric environments. The L os Alamos nuclear microprobe was used to determine in situ TE abundanc es in minerals from the Ubehebe Peak contact aureole and from Apennine ophicalcites. In these two crustal environments, known to have experi enced significant fluid flow, TE variability in minerals zoning in gra ins, analyses of multiple mineral generations in single samples, and a nalyses of grains from spatially-resolved hand-samples provides inform ation on the chemical evolution of fluid-flow systems during geologic processes. (C) 1997 Elsevier Science B.V.