9706629 Duke This project will examine potential applications of spectroscopic methods to supplement traditional methods of field mapping to extend the results of modern laboratory analysis to regional-scale, high-spatial-resolution maps of metamorphic terranes. It is proposed that spectroscopic methods can be used to produce maps of mineral distribution, maps of relative or absolute mineral abundance, and amaps of chemical variation. Tasks include: (1) forward modeling of simple metamorphic reactions using library mineral spectra to evaluate the spectral response of metamorphic processes, (2) inverse modeling of spectra of synthetic mixtures and natural rocks to evaluate and improve the accuracy of spectral decomposition methods for estimating mineral abundance, (3) correlation of mineral-chemical variations with spectral adsorption band shifts to evaluate the sensitivity of spectroscopy, (4) conduct new field studies to test results of tasks 1-3, (5) evaluate the applicability of spectroscopic methods to low-grade metamorphism through analysis of synthetic mixtures, natural samples, and field studies and (6) convolve model and real rock spectra to spectral resolutions of current and planned remote sensing spectrometers to evaluate the sensitivity of different sensors to metamorphic processes. The greatest impact of this research will be to develop the framework for integrating these new techniques into the study of metamorphic processes.
