[Study on exploring for gas based on analysis of spectral absorption features].
Da-Qi Xu1, Guo-Qiang Ni, Li-Li Jiang
1Department of Optical Engineering, School of Information Science and Technology, Beijing Institute of Technology, Beijing 100081, China. rufus7@yahoo.cn
Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu
|February 12, 2008
Summary
This study uses reflectance spectra to identify surface anomalies linked to hydrocarbon microseepage, aiding oil and gas exploration. A spectral library and improved detection methods enhance mineral alteration analysis in the Qinghai X X area.
Area of Science:
- Geophysics and Remote Sensing
- Mineralogy and Geochemistry
Context:
- Visible and near-infrared reflectance spectra offer rapid mineralogical and chemical composition analysis.
- Hydrocarbon microseepage theory links oil/gas reservoirs to observable surface anomalies.
Purpose:
- To explore for oil and gas by analyzing reflectance spectra of surface anomalies.
- To present macroscopic features of reflectance spectra in gas fields.
- To build a spectral library for the Qinghai X X area for rapid mineral alteration detection.
Summary:
- Analyzed reflectance spectra from 144 field samples in Qinghai X X area.
- Extracted absorption-band parameters (position, depth, width, asymmetry).
- Improved methods for detecting hydrocarbon microseepage using spectral data.
- Studied a linear unmixing model for semi-quantitative mineral abundance fractions.
Impact:
- Enhanced rapid and reliable detection of mineral alterations.
- Provides a foundation for improved hydrocarbon microseepage detection.
- Facilitates semi-quantitative mineralogical mapping in exploration areas.
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