Mineralogy and Geochemistry of the Black Shales, Selangor

This report presents the mineralogy and geochemistry of Black Shales at new outcrop located near Rawang, Selangor. However, nothing has been published regarding their geology, composition and maturation of this new outcrop. The study area probably an extension of Kenny Hill Formation from Carboniferous-Permian age based on the lithological setting of the exposed outcrop. Representative samples from different localities of the black shales were subjected to detailed mineralogical and geochemical analysis to compare with Kenny Hill Formation. These studies also provide an opportunity to investigate the maturation and possible potentiality of these black shales as shale gas. From XRD clay fraction analysis, these black shales composed of clay minerals including illite, kaolinite, and some smectite show variations among the studied samples. The TOC analysis gives ranges of TOC values between 0.9 and 16.5 wt% and shows that this black shales characterized as fair to excellence source rock. Based on FTIR analysis, the analyzed samples contain the aromatic hydrocarbon compound and two groups of aliphatic hydrocarbon i.e. alkenes and alkynes. Generally, the dominance in aromatic compared to aliphatic compound shows that source rock in this study area can be originated from Type III kerogen typing. Thus, this study area is possibly equivalent to the reported Kenny Hill Formation in term of the mineralogy and geochemistry and also this black shales is considered as overly matured with generally high illite/smectite ratio over 75% across the black shales lithology.