Browsing by Author "Bindhyachal Pandey"

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A new ammonite Geticeras gen. nov. from the Lower Valanginian (Lower Cretaceous) of the Spiti Valley, Tethys Himalaya, India
(Wadia Institute of Himalayan Geology, 2018) Bindhyachal Pandey; Deo Brat Pathak; Anand Kumar Jaitly
A new neocomitin ammonite taxon Geticeras getensis gen. et sp. nov. is systematically described from the poorly fossiliferous part of the Giumal Formation exposed near the village Gete, Spiti Valley, Tethys Himalaya, India. The characteristic ribbing of Geticeras, particularly on ventro-lateral shoulder and its tabulate venter, distinguish it from other genera of the Subfamily Neocomitinae. Based on the recent documentation of the globally spread ammonite genus Olcostephanus Neumayr from the same stratigraphic section, an Early Valanginian age is assigned to Geticeras gen. nov. © 2018, Wadia Institute of Himalayan Geology. All rights reserved.
A new approach to the correlation of the Upper Kimmeridgian Beckeri Zone across the Tethyan Sea
(E. Schweizerbart'sche Verlagsbuchhandlung, 1996) Günter Schweigert; Jai Krishna; Bindhyachal Pandey; Deo Brat Pathak
Based on a preliminary attempt of high resolution subdivision of the Upper Kimmeridgian Beckeri Zone of Southern Germany into ammonite faunal horizons, and on recently collected ammonites from the Kachchh area (India), the lineage of the ammonite genus Hybonoticeras is outlined. In consequence it is now possible to make much more precise correlations around the Kimmeridgian/Tithonian boundary (Beckeri/Hybonotum Zones) all across the Tethyan realm and its adjacent areas (e. g. Submediterranean of Europe, Indo-East-African province, Mexico).
A Preliminary Evaluation on the Prospects of Hydrocarbon Potential in the Carbonaceous Shales of Spiti and Chikkim Formations, Tethys Himalaya, India
(Geological Society of India, 2018) Bindhyachal Pandey; Deo Brat Pathak; Neeraj Mathur; Anand K. Jaitly; Alok K. Singh; Prakash K. Singh
In the present investigation, an attempt has been made to explore the possibility of hydrocarbon prospects in the carbonaceous shale deposits of Spiti and Chikkim formations exposed in the Spiti valley of the Tethys Himalaya. Twenty samples, collected from successive levels of these litho-units, have been subjected to maceral analysis, Rock-Eval Pyrolysis and six samples to Fourier Transform Infra-red Spectroscopy (FTIR) and nuclear magnetic resonance (NMR) analyses. The study reveals the presence of mainly kerogen-III type of organic matter but some of the shale samples have shown a good amount of total organic carbon (TOC) to the tune of 3.19% which is sufficient to produce hydrocarbon. The results indicate the presence of methane occurring as free and fixed hydrocarbon in the shale samples. Few levels are especially rich in hydrocarbon. They have shown encouraging results with potential for generating liquid as well as lighter hydrocarbon. The data is also supported by the FTIR and NMR studies. © 2018, Geological Society of India.
Ammonoid biozonation in the lower Albian (Lower Cretaceous) succession of the Ariyalur Sub-basin, Cauvery basin, south India
(Palaeontological Society Of India, 2021) Bindhyachal Pandey; A.K. Jaitly; J.P. Gautam; D.N. Tiwari
The ever-recognized Lower Albian succession of the Cauvery Basin has been revisited in conjunction with the revision of the exact extent of the Lower Albian horizons. This work also entails the formulation of ammonoid biozones in the précised Lower Albian record in the Ariyalur Sub-basin of the Cauvery Basin. This endeavor embodies the formal creation of Tetragonites rectangularis Zone in the revised Lower Albian sedimentary record of the Cauvery Basin for the first time which has been further differentiated into four Beudanticeras newtoni, Beudanticeras revoili, Jauberticeras collignoni, and Jauberticeras villoutreysi subzones in ascending order. The occurrences of distinctive Lower Albian ammonoid fauna in the Tetragonites rectangularis Zone make its close resemblance with Douvilleiceras mammillatum Zone of the standard ammonoid zonal framework. This biostratigraphic refinement is a noteworthy input in the marine Cretaceous biostratigraphy of the Cauvery Basin. It will also enhance the knowledge of the exposed marine Lower Cretaceous sedimentary record in India and abroad. © 2021 Palaeontological Society Of India. All rights reserved.
Biostratigraphic implication of Olcostephanus Neumayr, 1875 (Ammonoidea) from the Lower Cretaceous Giumal Formation, Spiti Valley, Tethys Himalaya, India
(Academic Press, 2017) Bindhyachal Pandey; Deo Brat Pathak
The paper records new species of the ammonoid genus Olcostephanus Neumayr from the Lower Cretaceous Giumal Formation exposed near Gete village in the Spiti Valley (Himachal Himalaya), India. Olcostephanus is one of the most significant genera for intrabasinal to intercontinental bio-chronostratigraphic correlation in view of its episodic global expansion during the Valanginian. This is the first report of Olcostephanus (Olcostephanus) sakalavensis (Besairie), Olcostephanus (Olcostephanus) cf. salinarius Spath, Olcostephanus (Olcostephanus) cf. fascigerus Spath and Olcostephanus (Olcostephanus) sp. indet., from the Indian Cretaceous. Based on close resemblance with the well-known biostratigraphically precised Mediterranean and South American Olcostephanus species, the present taxa are placed in the Neocomites platycostatus Subzone of the Karakaschiceras inostranzewi Zone to the Saynoceras verrucosum Subzone of the Saynoceras verrucosum Zone interval of the Standard Tethyan Scheme developed in Mediterranean of Europe. A possible correlation with Olcostephanus bearing stratigraphic horizons of South Africa, Madagascar and Pakistan is also proposed. The findings also confirm a significant eustatic rise close to the lower/upper Valanginian boundary. © 2016 Elsevier Ltd
Calliphylloceras heterophylloides (Oppel, 1856) from the basalmost jurassic succession of Sadhara Dome, Kachchh, India
(Palaeontological Society Of India, 2014) Bindhyachal Pandey; Deo Brat Pathak; Jai Krishna
We record and illustrate a septate (85 mm D) Calliphylloceras heterophylloides (Oppel, 1856) from the basalmost sediments of Sadhara Dome near the eastern end of Goradongar, Patcham 'Island', Kachchh, India. This is the oldest ammonoid-bearing horizon of the exposed Mesozoic sediments in the Kachchh Basin. In view of the correlation of the Late Bajocian Leptosphinctes bed of Kaladongar to the base of bed 32 of our column which is about 164 m younger than the Calliphylloceras-bearing bed 2, the age of present Calliphylloceras-bearing horizon is suggested here as Early Bajocian or older.
Carbonate Fan Fabric Structures (FFS) in time and space: A case study from the Palaeoproterozoic Kajrahat Limestone, Vindhyan Supergroup, India
(Palaeontological Society Of India, 2021) Divya Singh; Mukund Sharma; Uday Bhan; Bindhyachal Pandey; S.K. Pandey; Deepak Singh
This paper describes and discusses the origin of the carbonate Fan Fabric Structures (FFS), a rare and typical feature of the Precambrian Eon, observed in the Kajrahat Limestone near the Kota area, Sonbhadra District, Uttar Pradesh, India. In the Kajrahat Limestone, FFS escaped later recrystallization and subsequent dolomitization which otherwise obliterates the depositional texture as noted in most of the Proterozoic carbonate deposits. Characteristic FFS is noted exclusively in the upper part of the Kajrahat Limestone, Semri Group, Vindhyan Supergroup. The FFS varies from microscopic to mesoscopic in size. The depositional environment of the hosting carbonate units is inferred with the help of FFS morphology and configuration. The absence of actual microfossils, however, is conspicuous suggesting very rapid lithification. The origin of aragonite crystals and the possible role of organisms in the formation of FFS are discussed. The study reveals that these carbonate fans were formed below the sediment-water interface by the interplay of sedimentation and vertically upward nucleation of the crystal. Low diversity of stromatolites is also present in the Kajrahat Limestone and the overlying Salkhan Limestone. The Rohtasgarh Limestone, the top-most unit of the Lower Vindhyan is, however, completely devoid of FFS and stromatolites therefore, it is inferred that the FFS are restricted in time and space. © 2021 Palaeontological Society Of India. All rights reserved.
Characterization of Dichotomoceras in the Oxfordian of Kachchh
(2009) Jai Krishna; Bindhyachal Pandey; Deo Brat Pathak
We report here the first Dichotomoceras of the Indian subcontinent at Kantkote (Wagad) in the proximal most exposed part of the Kachchh Basin. This is further addition to the significant enlargement of the Oxfordian ammonoid record made earlier (Krishna et al. 1994, 1995, 1998,2000). Near continuous presence of ammonoids has been recorded in ca 55 m thick succession, almost immediately above the Schilli Subzone, that was considered ammonoid devoid earlier. The ammonoid density, diversity and frequency in this just discovered ca 55 m thick column are much scarcer in comparison to the underlying 10 m thick ammonoid abundant Schilli Subzone. Examples of Dichotomoceras are determined almost throughout the said interval which in our preliminary taxonomic evaluation appear identical or close to D. rotoides (Ronch.), D. stenocycloides (Siem.), D. bifurcatus (Quenst.) and D. crassus Enay. It thus suggests the characterization of the Rotoides Subzone of the Transversarium Zone and the superjacent Bifurcatus Zone of the column at least up to the early Late Oxfordian. ©GEOL. SOC. INDIA.
Development of Oxfordian (Early upper jurassic) in the most proximally exposed part of the Kachchh basin at Wagad outside the Kachchh Mainland
(1998) Jai Krishna; Deo B. Pathak; Bindhyachal Pandey
Over a century and half the Kachchh Oxfordian ammonoid record has remained restricted to Early and early Middle Oxfordian, that too in extremely condensed/reworked/starved sedimentary facies. In this backdrop we here discuss the Middle and Late Oxfordian ammonoid faunas recently discovered in Wagad (Krishna et al. 1994a, b). Among these the mid Middle Oxfordian stratigraphic interval is found exceptionally rich in ammonoids at Kantkote - the richest ever discovered in the Kachchh basin. It is made up of a 10 m thick succession of 13 ammonoid levels. Farther up after a thick ammonoid-devoid sediment interval appear again a few rather ammonoid scarce levels of late Late Oxfordian age with doubtful extension into early Early Kimmeridgian. The Oxfordian/Kimmeridgian boundary may be included in the latter of the two ammonoid bearing intervals in the Orthosphinctes/Lithacosphinctes levels. The rich mid Middle Oxfordian ammonite fauna inspite of being known for over a century from loose imprecise, unlocalised collections has been stratigraphically precise and dated for the first time in the relatively unexplored, stratigraphic section of Wagad. The ammonoid abundant mid Middle Oxfordian Transversarium Zone succession in addition of the restricted Indo-East African mayaitins and widely distributed perisphinctins includes a few examples of the Mediterranean Gregoryceras gr. fouquei, Euaspidoceras and Taramelliceras and suggests maximum flooding and eustatic rise in the Kachchh Mesozoic in the Middle Oxfordian Schilli Subzone of the Transversarium Zone. Another significant aspect of this fauna is the marked continuous presence of the compressed platyconic densely costate lithacoceratins (Larcheria and Discosphinctes) stocks in parallel with the true perisphinctin and mayaitin lineages almost althrough the Middle Oxfordian (Krishna et al. 1994a, b, 1995, 1996a). The mayaitins are for the first time precisely ranged up to the Transversarium Zone. The basin margin Oxfordian ammonoid succession at Wagad shows recurrence only of small portion in its basal part of the previously known Oxfordian section of the Kachchh Mainland (e.g. the common Perisphinctes-Epimayaites assemblage of bed G Lakhapur). The remainder ca 200 m thick Oxfordian at Wagad is interpreted here to correspond to the non-depositional submarine stratigraphic gap elsewhere in the relatively deeper parts of the basin from the later part of the Middle Oxfordian Plicatilis Zone to the early Early Kimmeridgian Hypselocyclum Zone.
Differentiation of the significant Late Valanginian (Early Cretaceous) transgressive event in the Spiti Himalaya, India
(2011) Deo Brat Pathak; Jai Krishna; Bindhyachal Pandey
Nearly continuous sedimentary succession of Early Cretaceous age has been long known in the Tethyan Himalayan belt without differentiation of the individual stages. We discuss here our just realised differentiation of a relatively thin well bedded sandstone interval with significant presence of the characteristic Late Valanginian-Early Hauterivian ammonoid genus Olcostephanus. It lies within a dominantly sandy succession with shale interbeds of Giumal Sandstone Formation, near Gate in Spiti Himalaya. This is the first stratigraphically precise record of Olcostephanus from the Cretaceous of India. It is here circumstantially age constrained to the Standard Tethyan Verrucosum Subzone Olcostephanus expansion event to the High Himalayan belt. © 2011 Elsevier Ltd.
Gregoryceras in the Oxfordian of Kachchh (India): Diverse eventful implications
(Elsevier Masson SAS, 2009) Jai Krishna; Bindhyachal Pandey; Jai Ram Ojha
The Kachchh Oxfordian ammonoid stratigraphic record for over 150 years remained restricted largely to Early Oxfordian condensed oolitic facies in the relatively distal Mainland Kachchh. Recently, it has been enlarged with the discovery in 1994 of over 200 m-thick uncondensed Middle to Late Oxfordian succession at Kantkote in the proximal part of the basin. Apart from abundant Perisphinctinae and Mayaitinae, a 10 m-thick sediment interval in the lower half of the above succession yielded a few examples of Gregoryceras. The specimens are here identified as G. gr. devauxi Bert and Enay and in view of their association with Larcheria subschilli (Lee) are assigned to the Middle Oxfordian Subschilli Horizon of the Schilli Subzone. Gregoryceras distribution south of the equator in Kachchh, Chile, Mexico and Madagascar, all within 35-40° latitude marks the southern limit of its latitudinal expansion during the first order maximum flooding surface (MFS) of the Schilli Subzone of the Kachchh Toarcian-Hauterivian Sequence. The maximum ammonoid diversity, density and frequency of the Kachchh first order sequence coupled with dominance of mayaitins and perisphinctins suggest over 20 m depth in the Gregoryceras interval. Distinctly greater bathymetry in the 200 km distally away basinal part causes sediment starved situation, and explains the Middle Oxfordian to early Early Kimmeridgian submarine nondepositional hiatus in the Mainland Kachchh. © 2008 Elsevier Masson SAS. All rights reserved.
Late Albian ammonites from the Cauvery Basin, south India
(Academic Press, 2019) Jai Prakash Gautam; Bindhyachal Pandey; Anand Kumar Jaitly; Deo Brat Pathak; Jens Lehmann; Deep Narayan Tiwari
A comprehensive taxonomic account of fourteen ammonite species from the upper Albian succession of the Cauvery Basin, south India is presented. They belong to the genera/subgenera Gaudryceras, Anagaudryceras, Tetragonites, Puzosia (Puzosia), Puzosia (Bhimaites), Desmoceras (Desmoceras), Desmoceras (Pseudouhligella), Stoliczkaia (Stoliczkaia) and the heteromorphs Anisoceras and Mariella. Most of these ammonite species are cosmopolitan and well-known, especially from the western margin of the Tethys. The additional value of this study in contrast to earlier studies is founded in the intensive bed-by-bed collection from a well-documented measured section. This allows to establish a first detailed range chart for the uppermost Albian of this region and to correlate the Cauvery Basin section with the upper Albian Mortoniceras perinflatum Zone-Arrhaphoceras briacensis Zone interval of the Standard Tethyan Scheme. © 2019
Late Tithonian (Late Jurassic) palynological record from the Jaisalmer Basin (India)
(Taylor and Francis Ltd., 2025) Raj Kumar; Bindhyachal Pandey; Neelam Das; Neha Aggarwal; Srikanta Murthy; Krishna Kumar; Deo Brat Pathak
Late Tithonian (Late Jurassic) palaeobotanical records from the Jaisalmer Basin are infrequent. We report the first record of an age-diagnostic palynological assemblage of the sedimentary rocks in the Bhadasar Formation from the Jaisalmer Basin, India. The study is carried out to consider the palaeoenvironmental settings in this basin based on palynological and palynofacies investigations. A well-preserved assemblage of palynomorphs with 22 species belonging to 10 genera, including spores and pollen. The palynological assemblage is characterised by the dominance of coniferous pollen of Callialasporites spp. Araucariacites spp. along with some significant taxa viz. Cupressacites ramachandra, Microcachryidites antarcticus, Classopollis sp. Podocarpidites sp. Pityosporites sp. Ginkgoretectina spp. and Monosulcites sp. which suggest a Late Tithonian (Late Jurassic) age. The occurrence of conifer pollens (Araucariacites and Callialasporites) represents coastal vegetation and warm climate. However, some bisaccate pollen (Podocarpidites) indicates drier upland areas. Palynofacies records suggest two distinct Palynofacies Assemblages (PA–I and PA–II) correspond to the marginal oxic to dysoxic basin and the shelf to marginal transition. © 2024 Informa UK Limited, trading as Taylor & Francis Group.
Late Tithonian (Late Jurassic) palynological record from the Jaisalmer Basin (India)
(Taylor and Francis Ltd., 2024) Raj Kumar; Bindhyachal Pandey; Neelam Das; Neha Aggarwal; Srikanta Murthy; Krishna Kumar; Deo Brat Pathak
Late Tithonian (Late Jurassic) palaeobotanical records from the Jaisalmer Basin are infrequent. We report the first record of an age-diagnostic palynological assemblage of the sedimentary rocks in the Bhadasar Formation from the Jaisalmer Basin, India. The study is carried out to consider the palaeoenvironmental settings in this basin based on palynological and palynofacies investigations. A well-preserved assemblage of palynomorphs with 22 species belonging to 10 genera, including spores and pollen. The palynological assemblage is characterised by the dominance of coniferous pollen of Callialasporites spp. Araucariacites spp. along with some significant taxa viz. Cupressacites ramachandra, Microcachryidites antarcticus, Classopollis sp. Podocarpidites sp. Pityosporites sp. Ginkgoretectina spp. and Monosulcites sp. which suggest a Late Tithonian (Late Jurassic) age. The occurrence of conifer pollens (Araucariacites and Callialasporites) represents coastal vegetation and warm climate. However, some bisaccate pollen (Podocarpidites) indicates drier upland areas. Palynofacies records suggest two distinct Palynofacies Assemblages (PA–I and PA–II) correspond to the marginal oxic to dysoxic basin and the shelf to marginal transition. © 2024 Informa UK Limited, trading as Taylor & Francis Group.
Microfacies analysis and depositional environments of the upper Cretaceous (Campanian-Maastrichtian) succession in the Cauvery Basin, southern India
(Palaeontological Society Of India, 2021) A.K. Jaitly; Bindhyachal Pandey; S.K. Mishra; D.N. Tiwari; J.P. Gautam
The Cauvery Basin of south India is an ideal reference section for the study of the marine Cretaceous (Aptian-Maastrichtian) sediments. The basin received more than 5500 m thick mixed siliciclastic and calcareous sediments in the course of intermittent phases of marine transgressions/regressions during Aptian-Maastrichtian time. The three microfacies-grainstone, packstone, and wackestone - have been broadly identified in the Campanian-Maastrichtian sediments of the Ariyalur Group of the Cauvery Basin. An attempt has been made here to use the distinctive features of these three microfacies and contained diverse bioclasts for the reconstruction of the physicochemical conditions to unravel the depositional history of this part of the Cauvery Basin, southern India. The facies analysis depicts a shallow marine (maximum depth 10 m) environment with an uninterrupted deepening from the Campanian to Middle Maastrichtian terminating into a basinal conditions during the Late Maastrichtian. The basin was well oxygenated with an average temperature (26°-28°C) of the Cretaceous sea and normal palaeosalinty range (30%-35%). These Campanian - Maastrichtian sediments are deposited on a carbonate ramp setting extending from the inner ramp to the marginal outer ramp. © 2021 Palaeontological Society Of India. All rights reserved.
Middle Eocene (Bartonian) vertebrate fauna from Bandah Formation, Jaisalmer Basin, Rajasthan, Western India
(Taylor and Francis Ltd., 2021) Krishna Kumar; Pragya Pandey; Sunil Bajpai; Debasish Bhattacharya; Bindhyachal Pandey
A small vertebrate faunal assemblage of late Middle Eocene (Bartonian) age is described from the Bandah Formation, a shallow marine deposit in the Jaisalmer Basin of Rajasthan state, Western India. The Bandah assemblage comprises representatives of selachians (sharks, rays), crocodilians, turtles and archaeocete cetaceans (archaic whales). The mammalian component of this fauna, though represented by fragmentary specimens, allows identification of two archaeocete taxa for the first time from the Palaeogene of Rajasthan: an unnamed protocetid close to Babiacetus and an andrewsiphiine remingtonocetid (Kutchicetus sp.). Occurrence of Eocene cetaceans in the Jaisalmer Basin brings to light a new, potentially rich cetacean-yielding horizon in India, and has the potential to allow a better understanding of early whale evolution in the Indian subcontinent. © 2020 Informa UK Limited, trading as Taylor & Francis Group.
New Ammonoid evidence for theJurassic/Cretaceous boundary in Kachchh Western India, and long distance correlation with Southern Europe
(1994) Jai Krishna; Deo Brat Pathak; Bindhyachal Pandey
The Jurassic/Cretaceous boundary in the ammonoid rich classic Jurassic region of Kachchh could not be precisedfor well over a century (1871-1991) due to the absence of ammonoids or other guide fossils of the Berriasian. Our present studies now firmly establish the basal Berriasian in Kachchh through close or identical ammonoids Aspidoceras cf. taverai Checa,, Argentiniceras loncochensis (Steur)), Spiticeras cf. ducale (Matheron)) and Berriasella sp. Relatively, among these, A. taverai Checa is considered a good marker of the basal Berriasian Jacobi Zone in the Subbetic Spain. Besides precising the Jurassic/Cretaceous boundary in Kachchh, A. cf. taverai Checa also allows long distance correlation to the precision of a single ammonoid zone across the Tethys between Kachchh (Indo-East-African province) on the south/east margin of the Tethys and Spain (Mediterranean province) on the north/west margin of the Tethys. The episodic presence of the ubiquitous Tethyan Aspidoceras in Kachchh during the Upper Kimmeridgian and basal Berriasian, interestingly, is found to correspond with phases of the eustatic rise of the Vail Cycles LZA 4.6 and LZB 1.4 which in turn suggests significant ammonoid faunal expansion events during the said intervals towards South and East from the Mediterranean to the Indo-East-African province. © 1994.
Palaeobotanical evidence for Artinskian wildfire in the Talcher Coalfield, Mahanadi Basin, India
(Palaeontological Society Of India, 2021) Deveshwar Prakash Mishra; Srikanta Murthy; Bindhyachal Pandey; Ashish Kumar Singh
The present endeavour documents the evidence of Artinskian wildfire from the Indian geological record by means of analysing macroscopic fossil charcoal fragments embedded in the coal bearing succession of Bharatpur Coal-mine in Talcher Coalfield, Mahanadi Basin, India. The palynological and SEM analyses record palaeobotanical evidence of this wildfire. The Scheuringipollenites barakarensis palynoassemblage of the present contribution assigns an Early Permian (Artinskian) age to the studied section and it also shows the dominance of glossopteridales, sub dominance of coniferales followed by cordaitales and filicales plant groups. The SEM study of macroscopic charcoal fragments exhibits anatomical features like homogenized cell walls, uniseriate simple, biseriate simple as well as alternate pitting patterns present on tracheid walls and also rays of varying heights signifying gymnospermous wood affinities. The good preservation and large size as well as almost unabraded edges of the charcoal fragments are indicative of a parautochthonous origin. © 2021 Palaeontological Society Of India. All rights reserved.
Palaeoecology and depositional setting of an Early Permian (Artinskian) mire based on a multi-proxy study at the Jagannath coal mine (Talcher Coalfield), Mahanadi Basin, India
(Elsevier B.V., 2022) Deveshwar Prakash Mishra; Vikram Partap Singh; Anju Saxena; Dieter Uhl; Srikanta Murthy; Bindhyachal Pandey; Raj Kumar
We report studies of petrography, palynofacies, charcoal and adpressed plant fossils for the coal-bearing Jagannath section in the Talcher Coalfield, Mahanadi Basin, India, to improve understanding of the age, palaeoecology and depositional setting of this palaeo-mire. Palynology is indicative of the Scheuringipollenites barakarensis assemblage, suggesting an Early Permian (Artinskian) age for the studied section. The age of the studied section is inferred based on correlation with coeval assemblages across Gondwana. Palynoassemblages have more similarity with those of Africa than South America. Petrographic indices suggest that peat-forming vegetation accumulated mainly in telmatic settings under ombrotrophic-mesotrophic (intermittent fluctuating) hydrological conditions. Palynofacies suggest that the deposition of organic matter (by high energy fluvio-deltaic agents) took place in an oxic to occasionally dysoxic setting. Megaflora comprise a low diversity assemblage dominated by Equisetales (Schizoneura and Paracalamites), with less common Glossopteridales (Glossopteris, Gangamopteris) and Filicales (Dichotomopteris) indicative of dense arborescent vegetation. Numerous fossil macrocharcoal fragments indicate the repeated occurrence of wildfires in the catchment area. The high abundance of pyrogenic inertinites in Permian coals of Gondwana may indicate a high-fire phase of Earth history linked to elevated atmosphere oxygen level, and our current study further substantiates this idea demonstrating the occurrence of fire, not only in seasonally dry ecosystems but also in peat forming ecosystems under humid conditions. Our multiproxy study is significant for understanding Permian peat-forming ecosystems and environments and provides a robust age assessment based on inter and intra-basinal correlations of coeval sequences across the Gondwana. © 2022
Palynofacies of the early Cretaceous Pariwar Formation, Jaisalmer Basin, Rajasthan, India: Palaeoenvironmental interpretation
(Palaeontological Society Of India, 2021) Raj Kumar; Neelam Das; Neha Aggarwal; Bindhyachal Pandey
Palynofacies analysis of the Early Cretaceous Pariwar Formation exposed near the Serawa village, Jaisalmer Basin, Rajasthan, western India has been carried out. Palynofacies data indicate that the Pariwar Formation are rich in degraded organic-matter. Based on the quantitative composition of the sediementry organic matter three distinct palynofacies associations are recognized (PF–1 to PF–3). PF–1 (predominance of the phytoclasts) is inferred as proximal suboxic to dysoxic shelf, PF–2 (dominated by AOM) is interpreted as distal dysoxic-anoxic shelf and PF–3 (predominated by phytoclasts alongwith AOM) is interpreted as shelf to marginal transition. Based on the distribution of palynofacies, it is inferred that the deposition of the Pariwar Formation took place in marginal to distal shelfal region in the marine setting. Recently discovered rich plant megafossil impressions, calcareous nannofossils and bioturbations in the successive horizons of the studied succession also indicate the presence of shallow marine condition at the time of deposition of the rock unit. © 2021 Palaeontological Society Of India. All rights reserved.