Browsing by Author "Anand K. Jaitly"

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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.
Approaches to palaeoecology: A case study from the Late Cretaceous (Campanian-Maastrichtian) benthic bivalves of Ariyalur, Tamil Nadu
(2007) Anand K. Jaitly; Sanjay K. Mishra
Palaeoecology has now become an imperative source for the palaeontologists in basin studies. The different concepts/principles and practices till recently used in palaeoecological investigations are reviewed and the organism-community concept, due to its simplicity and more practicalibilty than holistic concept, is followed here. About 1,300 bivalves have been collected from the Campanian-Maastrichtian (Late Cretaceous) sediments exposed in and around Ariyalur in Tamil Nadu. These benthic bivalves belong to four associations (determined by Q-mode cluster analysis). The trophic behaviour of these bivalves depicts that epifaunal suspension-feeders more or less dominated throughout the Campanian-Maastrichtian times and preferred firm fine- to medium- sandy carbonate substrates. Rarefaction, richness and evenness have been used to determine the diversity values of different associations, which vary from high to low. The different palaeosynecological approaches indicate that the Campanian Sillakkudi Formation reflects relatively low energy conditions in comparison to younger horizons (Maastrichtian) of the sub-basin where bivalves apparently colonized a shifting high-energy substrate. The palaeosalinity from the Sillakkudi Fromation up to the Ottakkovil Formation ranged between brachyhaline to euryhaline with temporary phases of hypersaline conditions. The uppermost Kallamedu Formation was deposited in an oligohaline salinity regime or even in a fresh water environment. The worldwide Late Cretaceous rise in the sea level is evidenced in the Cauvery basin by maximum flooding during the Middle Maastrichtian. Sedimentation took place in a high energy, neritic carbonate ramp setting. The carbonate ramp was replaced by a siliciclastic ramp in the late Middle Maastrichtian (Ottakkovil Formation). © Geol. Soc. India.
Campanian-Maastricthian (Late Cretaceous) veneroids (Bivalvia: Heterodonta) from the Ariyalur Group, South India
(2009) Anand K. Jaitly; Sanjay K. Mishra
Eleven veneroid (Bivalvia) species are systematically described from the Campanian-Maastrichtian (Late Cretaceous) sediments of Ariyalur sub-basin of South India. Among these, only Crassatella (Crassatella) macrodonta (Sowerby) and Arctica lacianata (Stoliczka) were earlier recorded by Stoliczka. Protocardia (Pachycardium) madagascariensis (Colignon), Protocardia (Pachycardium) pauli (Cocquand), Epicyprina angulata (Sowerby), Venilicardia truncata (Sowerby), and Calva (Egelicalva) buttensis (Anderson) were previously unknown from the Late Cretaceous horizons of the Indian sub-continent. The present record also includes a new species Palaeomoera stoliczkai n. sp. erected on the basis of its unique hinge characters and surface features. Lucina (Lucina) cf. fallax Forbes, Nicaniella (Nicaniella) aff. trigonoides (Stoliczka), and Corbicula? sp. indet., are tentatively identified because of their imperfect preservation. The present record may add useful information to the understanding of the Late Cretaceous palaeobiology of the region. © 2009 Elsevier Ltd and Nanjing Institute of Geology and Palaeontology, CAS.
Comments on Placenticeras mintoi (Vredenburg, 1906) from the Bagh Beds (Late Cretaceous), central India with special reference to Turonian Nodular Limestone Horizon
(2013) Anand K. Jaitly; Rahul Ajane
The Late Cretaceous (Cenomanian to Coniacian) marine sediments of central India prevalently known as 'Bagh Beds,' have been deposited in the E-W extending Narmada Basin. The stratigraphy of these Cenomanian - Coniacian sediments has been reviewed and summarized. The Bagh Beds have been found to consist of three formations: Nimar Sandstone, Nodular Limestone and Corallian Limestone in ascending order. Main emphasis has been given to Nodular Limestone Formation (Turonian), which is the most fossiliferous horizon of the Bagh Beds. Nodular Limestone Formation has more or less alternating bands of varying thickness of nodular limestone and marl. It yielded numerous ammonoid specimens, which have been found to belong to a morphologically highly variable ammoniod taxon Placenticeras mintoi Vredenburg. © 2013 Geological Society of India.
Comments on the middle jurassic pholadomyoids of Kachchh, Western India
(Palaeontological Society Of India, 2014) Anand K. Jaitly
The pholadomyoids (Anomalodesmata: Bivalvia) in Kachchh is represented by the genera Pholadomya, Pholadomya (Bucardiomya), Pholadomya (Indomya), Agrawalimya, Homomya, Pachymya, Pachymya (Arcomya), Ceratomya, Ceratomyopsis, Gerardotia, Goniomya, Machomya, Osteomya, Pleuromya, Platymoidea and Thracia. All of these pholadomyoids have been earlier recorded from the Middle Jurassic (Bathonian-Callovian) sediments of the different parts of Kachchh Mainland as well "islands". The genus Agrawalimya and the subgenus Indomya are endemic, while others are cosmopolitan in distribution and common elements of the Ethiopian Faunal Province. The pholadomyoids have been reviewed comprehensively and accordingly, the diagnostic morphological characters of some of these genera/species have been emended.
Discovery of the oyster Hyotissa semiplana (Sowerby, 1813) from the Campanian (Late cretaceous) of South India
(Palaeontological Society Of India, 2014) Anand K. Jaitly; Sanjay K. Mishra
The oysters are the most dominant elements in terms of diversity and preservation in the Late Cretaceous (Campanian-Maastrichtian) bivalve benthic palaeocommunities of Ariyalur (south India). These oysters belong to the families Gryphaeidae, Exogyridae and Oystreidae. Here, the oyster genus Hyotissa and the species Hyotissa semiplana (Sowerby1813) has been for the first time recorded from the Late Cretaceous (Campanian) of south India or even from the Indian subcontinent. The taxonomic status of the genus Hyotissa has been reviewed and H. semiplana has been systematically described with a brief autecological note.
Environments and faunal patterns in the Kachchh Rift Basin, Western India, during the Jurassic
(2004) Franz Theodor Fürsich; John H. Callomon; Dhirendra K. Pandey; Anand K. Jaitly
Marine Jurassic sediments (Bajocian-Tithonian) of the Kachchh Basin were deposited in a ramp setting. Except during the Middle and Late Bathonian, when a carbonate regime became established, the fill of the basin consists predominantly of siliciclastics. The sediments represent environments that range from coastal plains (rivers and associated flood plains with caliche nodules), deltas, brackish water lagoons, nearshore sand and iron-oolite bars of the inner ramp, generally situated above fair-weather wave-base, to the middle ramp influenced by storm-waves and by storm-generated currents, and finally to the outer ramp which is characterised by low energy, fine-grained sediments. Changes in relative sea level produced a cyclic sedimentation pattern. The rich benthic fauna of macroinvertebrates is dominated by bivalves, followed by brachiopods, gastropods, corals, serpulids, and sponges. The analysis of 370 statistical samples and more than 27,000 specimens produced more than 40 benthic associations and assemblages. They show a relationship to several environmental parameters, two of which, salinity and climate, are briefly discussed. The spatial distribution of the facies and biota is outlined for two time slices, the Bathonian and the Callovian-Oxfordian, respectively.
Faunal response to transgressive-regressive cycles: example from the Jurassic of western India
(1991) Franz T. Fürsich; Wolfgang Oschmann; Anand K. Jaitly; Indra Bir Singh
Upper Callovian to Oxfordian shelf sediments at Ler in the Kachchh Basin, western India, are interpreted in terms of transgressive-regressive cycles. The transgressive phases are represented by thin layers of reworked and bored concretions, sometimes in association with skeletal concentrations, the regressive phases are documented by much thicker units of largely fine-grained sediments. The benthic fauna of transgressive and regressive phases differes markedly and thus mirrors the sedimentary cycles: During transgressive phases non-sedimentation produced hard substrates colonized mainly by byssate, cemented, or pedicle-attached suspension-feeding epifaunal species, whilst sediment input during regressive phases lead to soft substrate conditions characterized by infaunal deposit- and suspension-feeders as well as by epifaunal opportunists. Whereas the composition of the "regressive fauna" remains fairly constant through time, that of successive "transgressive faunas" often differs drastically. This is possibly due to a greater environmental sensitivity of epifaunal taxa as compared to infaunal taxa. © 1991.
First record of Pressastarte zakharov and Pinguiastarte kelly (mollusca: Bivalvia) from the turonian (upper cretaceous) of the bagh beds, central India
(Palaeontological Society Of India, 2015) Anand K. Jaitly; Susheel Kumar; B. Pandey
The genus Pressastarte Zakharov, 1970 and the subgenus Pinguiastarte Kelly, 1992 (Family Astardiae) have been recorded from the Turonian (Upper Cretaceous) of the Bagh Beds, central India for the first time. The Pressastarte Zakharov is represented by two species: Pressastarte (Pressastarte) lincolnshirensis Kelly 1992 and Pressastarte (Pressastarte) var. clavertensis Duff, 1978 in the Bagh Beds. Pressastarte (Pinguiastarte) senecta (Woods, 1906) and Pressastarte (Pinguiastarte) var. pressula Zakharov 1970 are the two recorded species of the subgenus Pinguiastarte. On the basis of the present record, henceforth the Pressastarte (Pinguiastarte) ranges from the Middle Jurassic (Middle Bathonian) to the Late Cretaceous (Turonian).
Implication of the Middle Jurassic pholadomyoids of Kachchh in the palaeobiogeography of the Middle East and South Asia: A review
(Geological Society of India, 2017) Anand K. Jaitly
The Kachchh basin is known world over for its rich occurrence of the Middle to Late Jurassic mollusks. The Middle Jurassic sediments in Kachchh range in age from Bajocian (possibly Aalenian) to Callovian. Amongst the Middle Jurassic benthic communities of Kachchh, the pholadomyoid bivalves are one of the dominant groups in both diversity and number. These are represented by 13 genera and 30 constituent species. Distribution of these bivalves was much affected by the evolutionary history of the basin which has been created due to inundation by Tethys sea owing to the opening of Arabian sea sometime in Middle Jurassic. By and large these fauna are typical of the southern Hemisphere and belonged to east African biochore of the Tethyan realm or to the so called Ethiopian faunal province. Analyzing the (palaeo-) autecological behavior of the studied pholadomyoid bivalves and their distribution pattern, an attempt has been made to ascertain the usefulness of these pholadomyoids in evaluating the Middle Jurassic paleobiogeography. © 2017, Geological Society of India.
Neocrassinid bivalves (Heterodonta) from the Middle Bathonian (Jurassic) of Kachchh, Western India
(1992) Anand K. Jaitly
Six bivalve taxa belonging to the genus Neocrassina Fischer have been described from Middle Bathonian (Middle Jurassic) rocks of Kachchh, Western India. Of these, Neocrassina (N.) ovata (Smith), TV. (N.) robusta (Etallon) and N. (N.) paphia (dďOrbigny) have been recorded previously from various parts of Europe, while Neocrassina (N.) pandeyi Maithani is an endemic faunal element as are Neocrassina (N.) sp. A and Neocrassina (N.) sp. B. The generic and sub-generic characters of Neocrassina are reviewed as are affinities of the taxa with closely related forms from India and other parts of the world. © 1992 E. Schweizerbart'sche Verlagsbuchhandlung.
Record of Tethyan gastropod genus Astrohelix Szabó, 1984 from late Bajocian (Middle Jurassic) of Kachchh, western India
(2012) Bindhyachal Pandey; Deo Brat Pathak; Anand K. Jaitly; Jai Krishna; M. Venkateshwarlu
We here present the first record and illustrate the planispiral gastropod genus Astrohelix Szabo, 1984 through its species Astrohelix (Bifldobasis) cf. hourcqui (Delpey, 1948) from the Late Bajocian (Middle Jurassic) sediments of Kachchh Mainland, western India.
Shell microstructure of late Cretaceous (Maastrichtian) oysters from Ariyalur, Tamil Nadu
(Geological Society of India, 2014) Anand K. Jaitly; Sanjay K. Mishra; Shrinjana Sen
The micro-morphological shell characters (both in optical microscope and SEM) have been used to discriminate in between oyster's sub-families Pycnodonteinae Stenzel 1959, Exogyrinae Vyalov 1936, Ostreinae Refinesque 1815 and Lophinae Vyalov 1936. These sub-families are represented by six constituent genera Phygraea (Phygarea) vesicularis (Lamarck 1806), Hyotissa semiplana (Sowerby1813), Curvostrea rouvellei (Coquand 1862), Ceratostreon pliciferum (Dujardin 1837), Agerostrea ungulata (Schlotheim 1813) and Rastellum (Arctostrea) pectinatum (Lamarck 1810) in the late Cretaceous (Maastrichtian) sediments of the Ariyalur area of Tamil Nadu, south India. The optical microscopic observations and SEM studies of the shells of these six genera clearly indicate that all the four sub-families consist of distinctive set of shell-microstructures. Sub-family Pycnodonteinae is characterized by predominance of vesicular, exogyrinae by prismatic, Ostreinae by cross foliated and Lophinae by foliated shell microstructures. Besides their characteristic shell microstructures, some additional microstructures are also visible in the shells of some of the genera of these four sub-families. © 2014 Geological Society of India.