A new method for the semiquantitative determination of major rock‐forming minerals with thermal infrared multispectral data: Application to THEMIS infrared data
A new method for the semiquantitative determination of major rock‐forming minerals with thermal infrared multispectral data: Application to THEMIS infrared data
复制标题
DOI：
10.1002/jgre.20160
复制
发表时间：
2013-10
期刊：
影响因子：
--
通讯作者：
Jun Huang;C. Edwards;S. Ruff;P. Christensen;Long Xiao
中科院分区：
文献类型：
--
作者：
Jun Huang;C. Edwards;S. Ruff;P. Christensen;Long Xiao
我们开发了一种新的方法（最小残差迭代光谱混合分析（LRISMA）），利用多光谱热红外数据半定量地确定主要造岩矿物（长石、辉石、橄榄石、高硅相和石英）。矿物子库是基于先验知识从矿物主库生成的，以产生一套真实的矿物端元组合来拟合目标光谱。对应于最小均方根误差（最佳拟合）的矿物丰度通常与之前对实验室测量的岩石样本的岩相学研究和对火星表面材料的热红外高光谱分析最一致，因为热发射成像系统（THEMIS）光谱的光谱范围和分辨率大大减少。LRISMA的准确性和再现性分别为~4-16%和~5- 20%，而岩相学和以前的高光谱研究的准确性为~5- 15%。LRISMA可用于半定量地细化小尺度（~1平方公里）地质特征的整体表面矿物学，并提供高质量的THEMIS光谱数据（高表面温度：>260 K，低大气不透明度：总冰< 0.04，总尘< 0.15），最终目标是更好地了解区域地质过程。
We have developed a new method (least residual iterative spectral mixture analysis (LRISMA)) to semiquantitatively determine major rock‐forming minerals (feldspar, pyroxene, olivine, high‐silica phases, and quartz) with multispectral thermal infrared data. Sublibraries of minerals are generated from a master library of minerals based on prior knowledge to produce a suite of realistic mineral end‐member combinations to fit the target spectra. Mineral abundances that correspond to the least root‐mean‐square errors (best fit) generally agree best with previous petrographic studies of laboratory‐measured rock samples and thermal infrared hyperspectral analysis of materials on the surface of Mars, given the greatly reduced spectral range and resolution of Thermal Emission Imaging System (THEMIS) spectra. The accuracy and reproducibility of LRISMA is ~4–16% and ~5–20%, respectively, while the accuracy of petrographic and previous hyperspectral studies is ~5–15%. LRISMA can be applied to semiquantitatively refine the bulk surface mineralogy of small‐scale (~1 km2) geologic features with high‐quality THEMIS spectral data (high surface temperature: >260 K, low atmospheric opacity: total ice < 0.04 and total dust < 0.15) with the ultimate goal of better understanding regional geologic processes.