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Aslam, M.
- An Exhumed Channel Sandstone body of Suraideval Formation (Lower Cretaceous), Saurashtra Basin, Gujarat: A Possible Example of Delta Distributary and Nearshore Deposit
Authors
1 Department of Geology, Aligarh Muslim University, Aligarh - 202002, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 37, No 4 (1991), Pagination: 359-364Abstract
An earthy brown, cross-bedded, channel sandstone body overlying a thinly bedded sequence of white sandstone and red shale of the Surajdeval Formation (Iower-Cretaceous) stands out as a low-lying flat-topped escarpment, about 3-4 m high and 30-60 m wide, alongside the village Dhaduka near Chotila on the Surendranagar-Rajkot highway. Plane ta ble survey brings out a sinuous pattern of the channel sandstone body longitudinally in the north-south direction all along the escarpment.Integrated evidence from geometry, lithofacies and paleocurrents suggest that the Dhaduka sequence is an example of exhumed channel bar of delta distributary, in association with thinly-bedded coastal plain (1ongshore/tidal current) deposits.
Keywords
Sedimentology, Surajdeval Fm., Gujarat, River delta.- Heavy Mineral Suite in the Barakar Sandstone of Moher-Subbasin, Singrauli Coalfield, Central India
Authors
1 Department of Geology, Aligarh Muslim University, Aligarh, IN
2 Geochemistry Section, NGRI, Uppal Road, Hyderabad, IN
3 Department of Geology, D. S. College, Aligarh, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 38, No 1 (1991), Pagination: 66-75Abstract
Heavy mineral analysis of the Barakar Sandstone from a drill core (117 m) from the Moher-Subbasin of the Singrauli coalfield shows relative abundance of epidote, zircon and rutile in the finer (.088-.074 mm) and garnet, muscovite and staurolite in the coarser (0.177-0.149 mm) fraction. Stratigraphically, the heavy species do not exhibit marked variation in their relative abundance, though garnet forms the bulk of the heavy crop at 94 m depth.
The study indicates that basic and acid igneous rocks, low to medium and high-grade metamorphic rocks, and metasedimentary rocks to the south and southeast of the study area, probably the Manpat ridge, supplied the bulk of the sediment debris during the early Permian Barakar times.
Keywords
Sedimentology, Barakar Sandstone, Singrauli, Gondwana.- Grain Size and Petrography of Mesozoic Rocks of Saurashtra Basin, Gujarat, Western India
Authors
1 Department of Geology, Aligarh Muslim University, Aligarh-202002, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 44, No 4 (1994), Pagination: 399-412Abstract
A provenance study was conducted on the Mesozoic rocks of Saurashtra basin, Gujarat, in which grain size, mineralogy and petrographical features of sandstones were integrated to arrive at an consistent interpretation.
Textural parameters suggest progressive variation in that mean grain size increases from Than (0. t 98 - 0.117 mm), Surajdeval (0.257 -0.213 mm), through Ranipat (0.5 -0.378 mm), to Wadhwan (0.716 - 0.469 mm). The bulk of the sandstones demonstrate positive (+) skewness in Than and Surajdeval implying that sandstones include greater admixture of fine sediments, as aganist those of Rani pat and Wadhwan which show excess of coarse admixture. By and large, the Dhrangadhra sandstone is moderately to well sorted (σ I=0.52 - 0.84 φ).
Petrographically, three types of sandstones constitute the Dhrangadhra group of formations, namely, quartzarenite, subarkose and sublitharenite, consisting of quartz, feldspar, lithic-fragments, and mica in order of abundance. Groundmass material consists of cementing material and matrix. Heavy minerals show a preponderance of granet, zircon, tourmaline, staurolite, rutile and epidote. The study reveals a mixed provenance, comprising of acid igneous, metasedimentary rocks of the Aravalli highlands outcropping in the northeastern part of the study area.
Keywords
Sedimentary Petrology, Mesozoic, Saurashtra, Gujarat.- Nearshore Coastal Sedimentation in the Early Cretaceous Ranipat Formation of Saurashtra Basin, Gujarat, Western India
Authors
1 Department of Geology, Aligarh Muslim University, Aligarh-202 002, IN