Integration of GIS, Laboratory and Magnetic Field Data Interpretation for Identification of Laterite Beds in Eastern Salt Range, Pakistan.

Abstract

The modern world prioritizes sustainable, environment friendly energy resources making mineral exploration a key factor for construction and development. Minerals play an imperative role in economic development as well as technological advancement of any country. With exploration focused primarily on hydrocarbon industry, mineral exploration of rare or industrial minerals has been largely an ignored topic in Pakistan. The objective of this study is to investigate the subsurface presence of regional features associated to the industrial laterite mineral, an ecofriendlier construction material, in economic quantity in the Eastern Salt Range of Pakistan. The methodology adopted for this study involves the geochemical analysis of samples obtained during geological field and remote sensing techniques of Principal Component Analysis (PCA), band rationing (BR), and advanced mineral mapping to validate the regional exposures in the area. Furthermore, the results have been integrated with magnetic data acquired in the vicinity of the villages Ratuchah and Pidh at final stage. Geochemical analysis of samples showed large percentage of quartz mineral with iron oxide as the second most abundant mineral. PCA provided clear segregation of the laterite beds, sand bodies, carbonates, and clay content present in the area. The PCA band combination of 7, 5, 4 was able to visualize the presence of left lateral strike fault in the subsurface. Band rationing combined with advanced mineral mapping helped in pinpointing the presence of iron oxides in laterite beds with a 98% confidence level. Furthermore, the magnetic data interpretation confirmed the presence of left lateral strike slip fault trending northeast to southwest. Reduction to Pole (RTP) mapped much smoother anomalies in contrast to the residual total magnetic intensity map. First vertical derivative enhanced the short wavelength anomalies caused by the ferromagnetic laterite beds and application of tilt derivative further resolved the extension of laterite beds confirming their presence towards the southwest region. Although the results obtained were feasible in achieving the objectives, however a more detailed study of the region with aeromagnetic data and additional geological samples for lab analysis involving XRF can be combined to further validate potential of the study area.