Among the surface sediments anomalies caused by hydrocarbon leakage of heavy oil reservoir

bleaching of red beds

enrichment of ferrous-iron and alterations of clay minerals and carbonates exhibit diagnostic spectral features. For heavy oil exploration in the western slope of Songliao Basin

ETM+7 image is used to identify anomaly caused by hydrocarbon leakage. Principal Component Analysis （PCA）

band ratio

and False Color Composition （FCC） are used in image process. Four principal components （PCs） including 1

3

4

5-PC3 （the third component of the PCA on band 1

3

4 and 5）

1

3

5

7-PC3

2

3

5

7-PC3 and 3

4

5

7-PC4 show steady spectral enhancement for the hydrocarbon-induced minerals. The PCs are combined with band ratios of 3/1

4/3 and 7/5 for FCC. Four FCC images are selected for hydrocarbon-induced area delineation. Result indicates that the identified anomalous area is related to the geological setting and consistent with the strata sections in most area.