Joyeeta Bhattacharjee
Articles written in Journal of Earth System Science
Volume 127 Issue 2 March 2018 Article ID 0029
Biplab Bhattacharya Joyeeta Bhattacharjee Sandip Bandyopadhyay Sudipto Banerjee Kalyan Adhikari
The present research is an attempt to assess the Barakar Formation of the Raniganj Gondwana Basin, India, in the frame of fluvio-marine (estuarine) depositional systems using sequence stratigraphic elements. Analysis of predominant facies associations signify deposition in three sub-environments: (i) ariver-dominated bay-head delta zone in the inner estuary, with transition from braided fluvial channels (FA-B1) to tide-affected meandering fluvial channels and flood plains (FA-B2) in the basal part of the succession; (ii) a mixed energy central basin zone, which consists of transitional fluvio-tidal channels (FA-B2), tidal flats, associated with tidal channels and bars (FA-B3) in the middle-upper part ofthe succession; and (iii) a wave-dominated outer estuary (coastal) zone (FA-B4 with FA-B3) in the upper part of the succession. Stacked progradational (P1, P2)–retrogradational (R1, R2) successions attest to one major base level fluctuation, leading to distinct transgressive–regressive (T–R) cycles with development of initial falling stage systems tract (FSST), followed by lowstand systems tract (LST)and successive transgressive systems tracts (TST-1 and TST-2). Shift in the depositional regime from regressive to transgressive estuarine system in the early Permian Barakar Formation is attributed to change in accommodation space caused by mutual interactions of (i) base level fluctuations in responseto climatic amelioration and (ii) basinal tectonisms (exhumation/sagging) related to post-glacial isostatic adjustments in the riftogenic Gondwana basins.
Volume 130 All articles Published: 3 February 2021 Article ID 0012 Research article
BIPLAB BHATTACHARYA JOYEETA BHATTACHARJEE SUDIPTO BANERJEE TAMANYA ROY SANDIP BANDYOPADHYAY
The sandstone-shale-coal succession of the Barakar Formation (early Permian) of the Raniganj Basin, India hosts low-diversity ichnoassemblages, containing ichnogenera
$\bf{Highlights}$
$\bullet$ Sedimentological–ichnological analysis signifies marine encroachment in Barakar Formation in peninsular India.
$\bullet$ Ichnoassemblages point to complex pattern of sediment–organism interactions with gross energy distribution.
$\bullet$ Sustained marine transgression event within the continental Gondwanaland during early Permian is visualized.
Volume 132 All articles Published: 9 September 2023 Article ID 0149 Research article
JOYEETA BHATTACHARJEE TALAT AHMAD
Bundelkhand Archaean–Proterozoic Granitoid Complex comprises of an amalgamation of older, deformed Palaeoarchaean Tonalite Trondjhemite Granodiorite (TTG) surrounded by the younger relatively undeformed Neoarchaean high-K calc-alkaline granites. These rocks commenced its evolution during the Palaeo-Archaean (3.3 Ga) and continued to Archaean–Proterozoic Transition (APT). Heterogeneity in granites from southwestern Bundelkhand Craton can be observed in their colour, textural feature and availability of mafic components, thereby dividing them into grey (mafic rich and intermediate variant) and pink granites, which further gets geochemically classified into Closepet-type granites (maBc-rich variant of grey granite: GG), Low Silica High Magnesium monzogranite (LSHM, an intermediate variant of grey granite: IG (for field classification purpose) and High Silica Low Magnesium monzogranite (HSLM, pink granite: PG) on the basis of their major elemental characteristics. The partial melting of the lithologically varied crust and the mantle/lithosphere took place approximately around the same time because of the incompatible element-enriched Cuids and melts. This caused the generation of granitoids from Bundelkhand to be varied in nature, resulting in the crustal evolution and stabilisation of the craton around ${\sim}$3.3 Ga followed by its steady reworking by ${\sim}$2.57–2.54 Ga. The Closepet type granite resulted from crust-mantle interaction and the monzogranites from crustal melting. Understanding the granitic emplacement within such a short time will help to further decipher the geodynamic changes and the crustal evolutionary processes that were operative during the APT in SW Bundelkhand craton.
$\bf{Highlights}$
$\bullet$ The manuscript focuses on the geodynamic evolution of the varied granites from SW Bundelkhand Craton.
$\bullet$ The granites are categorised into grey (mafic-rich grey and intermediate grey) and pink granite on the basis of field geology and petrology. Geochemically they are divided into Closepet type granites (mafic-rich variant of GG) and monzogranites (low silica high magnesium: LSHM, intermediate variant of GG and high silica low magnesium: HSLM, pink granite variant). Their field expressions and the corresponding geochemical signatures can be attributed to a combination of partial melting and fractional crystallisation.
$\bullet$ The division of granites into a low-silica high-magnesium group indicates crust–mantle interactions (Closepet-granites), and a high-silica low-magnesium group points toward pure crustal melting (monzogranites).
Volume 132, 2023
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