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The influence of marine components in the study area is attributed to seafloor spreading and opening in the Indian Ocean during the Aptian, coupled with eustatic sea-level rise throughout the Aptian–Albian period. The present investigation delineates a marine incursion in the Chintalapudi sub-basin of the Godavari Valley Coalfield based on the occurrence of dinocysts, acritarchs and prasinophytes. Noteworthy stratigraphic marker taxa are recognized as key components in the age assignment of the sedimentary rocks. Sum total of four zones have been recognised in the studied part of the sequence. The oldest zone in the deepest set of sedimentation is identified as Cicatricosisporites australiensis Zone. This zone is assigned based on the first occurrence (FO) of Cicatricosisporites australiensis and Biretisporites eneabbaensis. The next zone, further above in the sequence is Foraminisporis wonthaggiensis Zone. The FO of Foraminisporis wonthaggiensis attested to the initiation of this zone. The third zone is Cyclosporites hughesii Zone recognised by the FO of Foraminisporis asymmetricus. The accessory palynotaxa comprised of Retimonocolpites sp., Tricolpites confessus, Tricolpites sp., Tricolporites sp. and Triporites sp. in the recognition of this zone. The youngest zone of this sequence is recognised at the top of the sequence named Crybelosporites striatus zone based on the FO of Crybelosporites striatus. Palynological analysis places the studied part of succession between the Berriasian to early Albian. The primary objective of this investigation is to explicate the characteristics of sedimentation and paleoenvironmental contexts, with a specific emphasis on utilizing palynofacies and Botryococcus morphotypes as distinct benchmarks. Based on the palynofacies investigation three different depositional regimes have been assigned, which are distinguished as follows: (a) continental (384.30–203.75 m) dysoxic–anoxic basin; (b) shallowest nearshore–inner shelf, marginal marine/brackish water settings; and (c) heterolithic proximal shelf deposition with significant sea transgression (94.50–36.50 m). Unpredictable morphotaxonomical responses across diverse habitats with varying pH levels are projected to enhance comprehension of the palaeoecological and palaeoenvironmental significance of fossil Botryococcus colonies. The uppermost marine part of the sequence denotes the least abundance, reduced size, and ill-defined amorphous forms of fossil Botryococcus colonies. The continental part displays the less abundant but well-defined and fully grown sporadic distribution of fossil Botryococcus colonies; the middle part records its presence with a well-diversified, sturdy structural framework and cellular cup-like structures. The investigation of the Cretaceous strata reveals a dynamic geological history influenced by tectonic activities, including plate drifting and rifting. Present investigation enhances our comprehension of palynostratigraphy, and paleoenvironmental history and facilitates the formulation of models elucidating environmental processes during the Early Cretaceous. In addition, the lipid-rich composition of Botryococcus renders it promising for biofuel production, attracting attention in biotechnology and renewable energy research endeavors. [ABSTRACT FROM AUTHOR]

Two linear NE–SW trending belts of platformal orthoquartzite-carbonate sequence, namely, the East Jahazpur Belt (EJB) and the West Jahazpur Belt (WJB), within a vast tract of slate–argillite–metagreywacke and subordinate metavolcanics of Hindoli Group (HG) together occur sandwiched between Vindhyan sediments to the east and Banded Gneissic Complex-II (BGC-II) to the west, at the eastern boundary of Aravalli Craton, Rajasthan, India. A NE–SW trending crustal-scale transpressive shear separates this low-grade supracrustal sequence from the gneisses of older Mangalwar Complex (BGC-II) to the west and the Great Boundary Fault (GBF) restricts it in the east against the Vindhyan rocks. A lensoid body of strongly deformed and mylonitised Jahazpur Granite (JG), is the basement for the supracrustal rocks and occupies the core of a SE verging D1-antiformal nappe defined by the EJB (Jahazpur Group-I) rocks. This large scale D1 thrust nappe structure in the EJB is manifested by stacking of early recumbent folds in the carbonate and quartzite units and a prominent zone of brecciation and ferruginisation all along the eastern margin of EJB. In the WJB (Jahazpur Group-II), D1 is represented by large scale isoclinal reclined fold geometry, likely to be influenced by the major transpressive shear and refolding at its western margin. D2 deformation phase, variably superposed over the D1 structures, together controls the NE–SW disposition of Hindoli and Jahazpur rocks. Based on the structural patterns and lithostratigraphic characters, we propose a revised stratigraphy of the Hindoli–Jahazpur rocks. Whole rock Rb–Sr dating of the strongly deformed and mylonitised Jahazpur Granite constrained the age of the tectono-metamorphic event that affected these rocks. Two suites of mylonitised Jahazpur Granite from two different localities yielded ages of 1423 ± 52 and 1393 ± 33 Ma, using Sector 54 TIMS. The tectonism that resulted in folding, thrust nappe, shearing and mylonitisation involving basement JG of Neoarchean age and the overlying Paleoproterozoic Jahazpur–Hindoli supracrustal sequences, therefore, represents a Mesoproterozoic (~1.4 Ga) orogeny that is correlatable with the breaking-up of Columbian Supercontinent along the eastern margin of the Aravalli craton. [ABSTRACT FROM AUTHOR]