Basaltic flows in the Laki Range of the Lower Indus Basin, Sindh, Pakistan: evidence for northwestern extension of the Deccan traps

摘要

The Deccan traps of India are one of the best examples of continental flood basalts.These basalts are abundantly exposed in the south-central part of India and have been studied in detail by many workers.Some 1300 km to the NW of Deccan, a sedimentary succession of Cretaceous-Tertiary rocks is well-exposed in the southern Lower Indus Basin of Pakistan.An unusual occurrence of volcanic rocks in the form of basalts is noted in this succession, both in the exposed and subsurface sections.These volcanic rocks are present in the form of meter-scale multiple flows within the Khadro Formation of Early Paleocene age.Some volcanoclasts are also observed within the Pab Sandstone of Late Cretaceous age.Although some work on these rocks has been carried out, no detailed studies have been performed on their petrogenesis and their possible relationship to the Deccan traps.