Surface Weathering Degree Mapping for Granite Using Reflectance Spectroscopy

Table 1. Maximum absorption depth in the vicinity of 2.2? wavelength

• Detecting the amount of clay minerals, such as kaolinite and illite, can be used to identify weathering degree of granite.
• Clay minerals on the surface of granite can be detected and measured using absorption peak of 2.2? wavelength in the reflectance curves.
• The presence of clay minerals, the evidence of weathering, was numerically converted to absorption depth.

• Clark, R.N., and Roush, T.L., 1984, Quantitative analysis techniques for remote sensing applications, Journal of Geophysical Research, vol. 89, p.6329-6340.
• Clark, R.N., 1999, Chapter 1: Spectroscopy of Rocks and Minerals, and Principles of Spectroscopy, Manual of Remote Sensing, 3rd ed., vol. 3, Wiley, New York, p.3-58.
• Clark, R.N., Swayze, G.A., Wise, R., Livo, K.E., Hoefen, T.M., Kokaly, R.F. and Sutley, S.J., 2003, USGS Digital Spectral Library splib05a, USGS Open File Report 03-395, http://pubs.usgs.gov/of/2003/ofr-03-395/ofr-03-395.html (accessed 30 May 2006).
• Kruse, F. A., Raines, G. L., and Watson, K., 1985, Analytical techniques for extracting geologic information from multichannel airborne spectroradiometer and airborne imaging spectrometer data, Proceedings of International Symposium on Remote Sensing of Environment, Thematic Conference on Remote Sensing for Exploration Geology, 4th, Environmental Research Institute of Michigan, Ann Arbor, p309-324.
• Kwon, S.T., Shin, K.B., Park, H.K., and Mertzman, S.A., 1995, Geochemistry of the Kwanaksan alkali feldspar granite: A-type granite?, The Korean Journal of Petroleum Geology, vol. 4, p.31-48.