Lithologic Mapping Using Geobotanical and Landsat Thematic Mapper Data

Richard W. Birnie, Nancy Defeo

Detailed work has been undertaken to study the correlations among Landsat TM spectral data, lithologic units, geobotanical forest associations, and geomorphic site parameters in the predominantly deciduous forest of the Valley and Ridge province, Pennsylvania. The TM spectral data are taken from the November 2, 1982, overpass at a time when some of the study area was undergoing fall senescence. The forest association data are based on over 250 1/10-acre surveys. The lithologies are primarily two clastic sedimentary units, sandstone and shales, each with a different geomorphic slope and aspect. Both the TM and forest association data can be divided into four groups representing unique lithologic and geomorphic site parameters. The first principal component of the TM data s parates the four lithologic/geomorphic units on the basis of their associated botanical and geomorphic site parameters. The second and third principal components contain information about forest density and canopy closure. It is apparent from this study that geobotanical forest associations are useful as indicators of lithology, and that changes in these forest associations are detectable with Landsat TM data from space.

AAPG Search and Discovery Article #91038©1987 AAPG Annual Convention, Los Angeles, California, June 7-10, 1987.