Staskowski, Ronald J.¹, Christopher M. Jengo², John R. Everett¹ 
(1) Earth Satellite Corporation, Rockville, MD 
(2) Research Systems Inc, Vienna, VA

ABSTRACT: Utility of ASTER for Detecting Hydrocarbon

Multispectral instruments, such as Landsat, have demonstrated they can detect subtle geochemical anomalies associated with hydrocarbon seeps. However, these geochemical anomalies are nonspecific, and require field verification. In contrast, hyperspectral instruments (such as AVIRIS) can readily differentiate between ancient hydrocarbon seeps and active hydrocarbon seeps. High cost, small area of coverage, and need for advanced image processing limit the use of hyperspectral data. The Advanced Spaceborne Thermal Emission and Reflection (ASTER) instrument is an excellent compromise between the two approaches. ASTER is a multispectral instrument, but includes more spectral bands in the shortwave infrared region where minerals associated with hydrocarbon seeps have identifiable absorption features. Analysis of ASTER data collected over Trap Spring and Eagle Springs fields in Nevada show that clay minerals more stable within the reducing environment of a seep (e.g., kaolinite) can be differentiated from other more disordered clays (e.g., illite, smectite, montmorillonite). The oxidation of ferrous iron bearing minerals (e.g., pyrite and marcosite), also common within reducing environments, can be differentiated to a higher degree than with Landsat TM data. A comparison of ASTER data collected over the Dutton Basin Anticline in central Wyoming with the results utilizing AVIRIS imagery, reveals the strengths and limitations of the ASTER sensor. ASTER data are an inexpensive and effective tool for mapping geochemical anomalies related to hydrocarbon seepage.

AAPG Search and Discovery Article #90026©2004 AAPG Annual Meeting, Dallas, Texas, April 18-21, 2004.