Geochemical analysis and spectral characteristics of oil shale deposits in Wadi Abu Ziad, Western Irbid, Jordan

Oil shale deposits with over 70 billion tons of proven reserves are considered one of Jordan's most important sources of energy. The current study investigated the mineralogy, geochemistry, and spectral characteristics of the Wadi Abu Ziad oil shales in northern Jordan. The mineralogical composition of the collected samples was analyzed using X-ray diffraction (XRD). Total organic matter (TOM) and calcium carbonate (CaCO3) contents were also determined. The spectral characteristics of oil shales were examined using a GER 3700 Spectroradiometer (0.35 to 2.5 µm) and Fourier transform infrared spectroscopy (FTIR) (4000 to 400 cm−1). XRD analysis revealed that the samples are composed primarily of quartz, calcite, and apatite. The average TOM and CaCO3 contents in the study area are 13.91% and 16.73%, respectively. The absorption features of oil shale samples are at 1.41 µm and 1.90 µm (H2O), 1.76 µm (C–H), 2.20 µm (Al–OH), and 2.33 µm (CO3). The FTIR absorption spectrum exhibits the absorption bands that characterize kaolinite, quartz (SiO2), calcite (CaCO3), and organic compounds in the oil shale samples. Spectroscopic analysis is a useful tool for identifying the mineralogical composition of oil shales and helps oil shale exploration using multispectral and hyperspectral remote sensing data.