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Macroscopic fossil charcoal fragments have been recovered from the borehole AK-19 (at a depth of 120.00 m) drilled at the Astona-Kothurna coal block, Wardha valley coalfield. In general, the occurrence of charcoal in sediments is accepted as a direct indicator for palaeo-wildfires. The charcoal fragments exhibits well preserved homogenized cell walls as well as anatomical details such as uniseriate and biseriate pitting patterns on tracheid walls under Field Emission Scanning Electronic Microscope (FESEM), suggesting a gymnospermous wood affinity of the studied material. The excellent preservation, their large size and almost unabraded edges of charcoal fragments suggest a par-autochthonous origin. These findings add further evidence for the widespread occurrence of such wildfires during the Early Permian not only in India, but on the entire Gondwana continent. [ABSTRACT FROM AUTHOR]

This work documents for the first time a palynological assemblage in the Rajmahal Basin, tentatively considered probable youngest Late Pennsylvanian assemblage, which was hitherto considered early Permian. The palynocomposition consists of 39 species (5 spores, 25 monosaccate, 5 bisaccate- 3 non striate and 2 striate grains, scarce Navifusa sp., scolecodont, algae and fungal hyphae). Two assemblages are described based on the first appearance of taxa, Assemblage I (608.90–599.00 m) dominated by monosaccates and absence of bisaccates and spores. Assemblage II (592.0–590.80 m) also dominated by monosaccates but with the inception of spores, bisaccates and marine palynomorphs. The Assemblage I is correlated to the oldest Potonieisporites neglectus Assemblage Zone of Tiwari and Tripathi based on their similarities and the absence of species recorded in the Assemblage II which is correlated to their overlying Plicatipollenites gondwanensis Assemblage Zone. Palynoassemblages similar to the Assemblage I, radiometrically constrained to the Late Pennsylvanian across Gondwana, along with the lack of diagnostic Permian pollen grains as well as marine Eurydesma fauna and terrestrial glossopterids, tentatively support an older age at least for the lower interval of the Talchir Formation. The latter fossils associated to Assemblage II confirm an early Permian age. [ABSTRACT FROM AUTHOR]

A palynological analysis of borehole RB-1, Raniganj Coalfield, Damodar Basin, has been presented here. Based on the quantitative analysis of the spores and pollen grains of the productive samples, three palynoassemblages have been identified: Palynoassemblage-I demarcated at a depth between 335.00 and 284.00 m is distinguished by the dominance of nonstriate bisaccate pollen Scheuringipollenites and subdominance of striate bisaccate pollen Faunipollenites suggestive of an early Permian (Artinskian) age; Palynoassemblage-II identified at a depth between 278.00 and 32.00 m shows the prominence of striate bisaccate mainly Faunipollenites, Striatopodocarpites and subdominance of Scheuringipollenites signifies late early Permian (Kungurian) age, and the youngest Palynoassemblage-III marked at a depth between 30.00 and 03.00 m contains dominance of striate disaccates pollen, viz., Striatopodocarpites, Crescentipollenites, and monosaccate pollen Densipollenites spp. (D. invisus, D. densus, D. magnicorpus) corroborate with the latest Permian Raniganj (Lopingian) age. The rare occurrence of Densoisporites contactus and Lundbladispora warti in the assemblage, define the upper limit of the Raniganj Formation. The assemblages have been correlated with the Indian as well as other Gondwanian continents. The dominance of gymnosperms pollen glossopteridales, conifers, and cordaites, lesser quantitative spores of lycopsids, sphenopsids, filiciopsids algal elements indicate that the palaeoclimatic condition was warm and high humid, during the deposition of these sediments in the study area of the Raniganj Coalfield. Research Highlights: Palynological study has been carried out for the subsurface coal deposits from the borehole RB-1, drilled at Raniganj Coalfield to attempt to establish chronology of the sediments. The palynological investigation reveals three palynoassemblage zones and dated as early to latest Permian (Artinskian to Lopingian) age and this assemblage reveals the dominance of gymnosperms plant group such as Glossopteridales followed by conifers and cordaitales. The FADs (First appearance of Datum) of Densoisporites contactus, Lundbladispora warti and Lunatisporites pellucidus in the assemblage III indicate the end of Permian period. The overall palynological composition suggests that a warm to very hot with medium to low humidity climatic condition were prevailing in the study area. [ABSTRACT FROM AUTHOR]

The Gondwana sediments comprising fine-grained shales, carbonaceous shales, sandstones and the coal horizon in borecore RT-4 (approximately 547.00m thick) from Tamra block, Raniganj Coalfield, Damodar Basin, are analyzed palynologically. Based on the distribution pattern of marker palynotaxa, two assemblage zones are identified. In the Barren Measures Formation, dominance of enveloping monosaccate ( Densipollenites) along with striate bisaccate ( Striatopodocarpites, Faunipollenites) pollen taxa, and the FAD's of Kamthisaccites and Arcuatipollenites observed at 30.75, have equated this strata (30.75-227.80 m thick) with the Raniganj Formation of Late Permian in age. Downwards in the Barakar Formation, between 423.80-577.70 m depths, an abundance of non-striate ( Scheuringipollenites) and striate ( Faunipollenites and Striatopodocarpites) bisaccate pollen taxa is observed, that dates late Early Permian in age. Fair occurrences of hyaline, distorted and blackish-brown plant matter is observed within 231.00-408.40 m depths. Present study infers the existence of the Raniganj Formation in the lithologically delimited Barren Measures Formation in the study area, and the underlying unproductive strata (approx. 177.40m) might represent the part of the Barren Measures Formation. [ABSTRACT FROM AUTHOR]

The present work elucidates miofloral records from the Ganmachidam Formation (late Carboniferous–earliest Permian) of Spiti Valley, Tethyan Himalaya. The Ganmachidam Formation was hitherto considered as unfossiliferous, both for the faunal as well as floral records, and has been subjected to contentious age assessment. The present study has been carried out to find out the microfloral remains, assess the palynostratigraphic status, and the age of the Ganmachidam Formation. From the splintery shale sequence, a rich assemblage of palynomorphs has been recovered, having a dominance of monosaccate pollen grains, namely Parasaccites (Cannanoropollis), Crucisaccites, Divarisaccus, Densipollenites, Maculatasporites, followed by diverse bisaccate pollen grains, namely Scheuringipollenites, Crescentipollenites, Faunipollenites (Protohaploxypinus), Lunatisporites, Striatopodocarpites, Striatites, Rhizomaspora, Primuspollenites, and the spores Callumispora (Punctatisporites) and Calamospora in addition to woody fragments and fungal spores. Three palynoassemblages are identified. The recovered palynocomposition is corroborated with known records of palynomorphs from the Tethyan realm of India and from the late Carboniferous–Early Permian records of contemporaneous sequences across the globe. The composition of these palynoassemblages shows close correlation with the Crucisaccites monoletus Zone and Vittatina costabilis Interval Zone in the northeastern area of the Paraná Basin, Brazil, and lower Barakar palynozone (Scheuringipollenites barakarensis Assemblage Zone) of Peninsular India which indicates the studied section of the Ganmachidam Formation is late Pennsylvanian to early Permian in age. Moreover, occurrences of palynomorphs from the Carboniferous sequences having a glossopterid affinity further strengthen the idea that glossopterids might have originated in Carboniferous time. [ABSTRACT FROM AUTHOR]

The palynostratigraphic data given here are based on the explored borecores (TRBD-2, TRBD-3 and TROD-1), by Geological Survey of India. The Permian strata worked-out is about 1174.00 m thick and comprises from base to top - Talchir, Barakar and Barren Measures formations. The palynological content enables delimitation of five palynological assemblages. (i) Scheuringipollenites barakarensis, (ii) Faunipollenites varius, (iii) Gondisporites raniganjensis, (iv) Densipollenites magnicorpus, and (v) Krempipollenites indicus in ascending order from the subsuface rock strata. The lithologically identified strata Talchir Formation in borecores TRBD-2 and TRBD-3 is palynologically dated late Early Permian in having the Scheuringipollenites barakarensis and the Faunipollenites varius palynozones. Subsequently, the part of Barakar strata in these borecores corroborates with Barakar Formation. In borecore TRBD-3, the Barren Measures rocks do not match with the palynological dates, and are affiliated with the palynoflora of the Raniganj Formation. In TROD-1, the strata identified as Barakar Formation is dated Late Permian in having Gondisporites ranigangensis Palynozone; while that of Barren Measures Formation is palynologically dated Early Triassic having Krempipollenites indicus Palynozone. The palynology has helped in the precise dating of the Lower Gondwana succession of Odari and Bartikhurd blocks in Tatapani-Ramkola Coalfield of South Rewa Gondwana Basin. [ABSTRACT FROM AUTHOR]

The Permian-Triassic (P/T) mass extinction qualifies as the severest biotic perturbation in the history of our planet. Biomarkers, stable isotopes and palynomorphs are excellent proxies offering glimpses into palaeobiota and past ecosystems. These were investigated from coal-bearing upper Permian (Raniganj Formation) and Lower Triassic (Panchet Formation) Gondwana sediments recovered from the Raniganj Sub-basin, eastern India. The geochemical and palaeobotanical data suggest a shift in the terrestrial vegetation during the Early Triassic. A distinct change occurs from high abundance of n -C 23 and n -C 25 alkanes and higher CPI values in the upper Permian sediments to predominantly n -C 27 and n -C 29 alkanes along with relatively lower CPI values in the Lower Triassic. A sharp decline of the diterpenoid compounds and Glossopteridales pollens with a concomitant rise in lycopsid spores in the Lower Triassic sediments reflects the waning of a gymnosperm-dominated mire and onset of a stressed environment. Unlike the Glossopteridales, the Coniferales appear to be a resilient floral group with several new genera adapting to the growing arid conditions in the Early Triassic. The microbial community also responded to the contemporaneous ecosystem shift, with higher concentration of C 27 sterane relative to C 29 sterane in Lower Triassic sediments indicating proliferation of algal phytoplankton. The decreasing moretane/hopane (M/H) suggests that the soil bacteria were adversely affected plausibly due to enhanced soil erosion at the early part of the Triassic. A marked shift in the bulk isotopic composition (δ13C org) from higher values in the upper Permian sediments (˗21.0 to ˗24.1‰) to lower values in the Lower Triassic sediments (˗21.2 to ˗32.5‰) is diagnostic of a vegetation changeover as a result of environmental deterioration. This is the first integrated study using molecular organic geochemical proxies and palynology from terrestrial Gondwana sediments in the Indian subcontinent, designed to investigate the pattern of floral and microbial restructuring as a result of an environmental shift during the Permian-Triassic transition. • Biomarkers, δ13C org and palynomorphs reported from Gondwana sediments, India. • Molecular and palaeobotanical proxies suggest a declining palaeomire. • Changeover of vegetation as a response to environmental shift could be discerned. [ABSTRACT FROM AUTHOR]

The late Cretaceous Corsinipollenites from central India and its nearest living fossil pollen Ludwigia from Pleistocene Karewa sediments in Kashmir shows morphometrical affinities with pollen of seven extant Ludwigia species (L. octovalvis (Jacq) P.H. Raven , L. octovalvis subsp. sessiliflora (M.Micheli) Raven , L. adscendens (L.) H. Hara , L. perennis (L.), L. hyssopifolia (G.Don) Exell , L. peruviana (L.) H. Hara and L. decurrens Walt.) commonly growing in swampy ecosystems of India. The Field Emission Scanning Electron Microscope (FESEM) and Light Microscope (LM) study draws plausible lineage of extant Ludwigia species with that of fossil specimens recovered at two different time frames based on similarities in pollen morphometry. The pollen aperture and its character along with the sexine pattern were main identifiable features to distinguish different species of extant/fossil Ludwigia pollen. The aspidote aperture varies from brevi-colporate to slit-like colpi (colporate). The sexine is stenopalynous type characterized by rugulate to reti-rugulate pattern. The multivariate principal component analysis (PCA) was applied on the numerical data obtained from pollen morphometry of living and fossil Ludwigia spp. The Pleistocene Ludwigia morphotype with slit-like colpi shows close proximity to L. octovalvis, L. octovalvis subsp. sessiliflora and L. adscendens. However, Late Cretaceous, Corsinipollenitis characterized by brevicolpi is closer to L. perennis and L. hyssopifolia with respect to primary pollen characters and inferred as primitive species having lineage to the "Old World" (paleotropical) species. A short pollen key of Ludwigia spp., is presented here to enable the identification of living/fossil pollen. • Morphometry and morphology of seven extant species of Ludwigia from India. • A plausible lineage of living Ludwigia with their fossil pollen records. • Pleistocene Ludwigia and L. octovalvis subsp. sessiliflora shares similar pollen characters. • Late Cretaceous, Corsinipollenitis is similar to L. perennis and L. hyssopifolia. • Ludwigia perennis and L. hyssopifolia are primitive species having lineage to the "Old World." [ABSTRACT FROM AUTHOR]

Secondary education among lower caste adolescent girls living in rural Karnataka, South India, is characterized by high rates of school drop-out and absenteeism. A cross-sectional baseline survey (N=2275) was conducted in 2014 as part of a cluster-randomized control trial among adolescent girls (13-14 year) and their families from marginalized communities in two districts of north Karnataka. Bivariate and multivariate logistic regression models were used. Overall, 8.7% girls reported secondary school dropout and 8.1% reported frequent absenteeism (past month). In adjusted analyses, economic factors (household poverty; girls' work-related migration), social norms and practices (child marriage; value of girls' education), and school-related factors (poor learning environment and bullying/harassment at school) were associated with an increased odds of school dropout and absenteeism. Interventions aiming to increase secondary school retention among marginalized girls may require a multi-level approach, with synergistic components that address social, structural and economic determinants of school absenteeism and dropout. [ABSTRACT FROM AUTHOR]