Spectroscopic Methods for Mapping Metamorphic Rocks

该项目将研究光谱学方法的潜在应用，以补充传统的野外测绘方法，将现代实验室分析的结果扩展到区域尺度、高空间分辨率的变质地层地图。提出光谱方法可用于绘制矿物分布图、相对或绝对矿物丰度图和化学变化图。任务包括:(1)利用矿物谱库对简单变质反应进行正演模拟，以评价变质过程的光谱响应；(2)对合成混合物和天然岩石的光谱进行逆模拟，以评价和提高光谱分解方法估算矿物丰度的准确性；(3)将矿物化学变化与光谱吸附带位移进行相关性分析，以评价光谱的灵敏度。(4)开展新的野外研究，以检验任务1-3的结果；(5)通过对合成混合物、天然样品和野外研究的分析，评估光谱方法对低变质作用的适用性；(6)将模型和真实岩石光谱与现有和计划中的遥感光谱仪的光谱分辨率进行卷积，以评估不同传感器对变质过程的灵敏度。这项研究的最大影响将是开发将这些新技术整合到变质过程研究中的框架。

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.