Irfan U Jan
Articles written in Journal of Earth System Science
Volume 123 Issue 1 February 2014 pp 21-32
This paper comprises of two sections. The first section describes challenges in the Carboniferous–Permian Gondwanan stratigraphic palynology, and progress in techniques such as presence of the ‘rare-marine intervals’, and ‘radiometric dating’ in some Gondwanan successions, e.g., South Africa, Australia and South America, as tools to confidently calibrate these palynozones. The second section describes developments in the palynological work on the Carboniferous–Permian Nilawahan Group of the Salt Range, Pakistan, and summarises their correlation with the coeval succession of the Gondwana continents and with the Russian/International stages.
Volume 124 Issue 4 June 2015 pp 747-766
The Lower Jurassic Datta Formation, western Salt Range, Pakistan, comprises three facies associations:
channel belt facies association (CBFA),
channel margin, and overbank facies association (CMOFA), and
lagoonal facies association (LFA).
A cyclic fining-upward trend in the succession is represented by basal quartzose conglomerate/pebbly sandstone, through coarse to fine quartzose sandstone to silt-stone and shales/claystone, which contains some carbonate accumulation. Two prominent depositional sequences are recognized in the Datta Formation with the lower high and upper low magnitude cycles. The Datta Formation thus represents a thick sedimentary succession and in the study area, i.e., western Salt Range, mainly channel belt, flood plain and/or delta top facies are exposed. The palaeocurrent analysis shows that the source area with acidic plutonic rocks laid to S–SE in the Indian shield, aravalies or older sedimentary rocks of the Indus Basin (i.e., Khewra, Tobra and Warchha formations). A tentative stratigraphic correlation of the Datta Formation with the lower Jurassic Lathi Formation, India invites further work in parts of India, which will elaborate the extent of the Datta Formation in the Greater Indian peninsula and develop palaeogeographic setting for this Lower Jurassic deltaic rock unit.
Volume 128 | Issue 8
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