Browsing by Author "Karisiddaiah, S.M."
Now showing items 1-20 of 43
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1300 km long late Pleistocene-Holocene shelf edge barrier reef system along the western continental shelf of India: Occurrence and significance
Vora, K.H.; Wagle, B.G.; Veerayya, M.; Almeida, F.; Karisiddaiah, S.M. (Elsevier, 1996)A detailed analysis of echosounding and side-scan sonar data collected from the western continental margin of India has revealed the presence of prominent shelf edge reefs, concentrated mostly on the central and the southern ... -
A note on incipient spilitisation of central Indian basin basalts
Karisiddaiah, S.M.; Iyer, S.D. (Geological Society of India, 1992)Rocks dredged in the vicinity of the 79 degrees E fracture zone, in the Central Indian Basin, are sub-alkaline basalts, which are regarded as precursors to spilites. The minerals identified are mainly albitic plagioclase, ... -
A note on the occurrence of ortho-amphibolites on the inner shelf off Bhatkal, west coast of India
Siddiquie, H.N.; Karisiddaiah, S.M.; Subrahmanyam, V. (Geological Society of India, 1987)The total magnetic intensity map of the area shows that the inner shelf to a depth of 50m is marked by a zone of magnetic closures. The occurrence of offshore orthoamphibolites and the qualitative interpretation of the ... -
An insight into the 'Fifty-Fathom-Flat' off India's west coast
Mukhopadhyay, R.; Fernandes, W.A.; Naik, Y.S.; Karisiddaiah, S.M. (Elsevier, 2010)The architecture of the western continental margin of India (WCMI) is likely to have been influenced in the geological past by several episodes of volcanic eruptions, rifting, and continental break-up. The WCMI is characterized ... -
Application of hybrid techniques (self-organizing map and fuzzy algorithm) using backscatter data for segmentation and fine-scale roughness characterization of seepage-related seafloor along the western continental margin of India
Chakraborty, B.; Menezes, A.A.A.; Dandapath, S.; Fernandes, W.A.; Karisiddaiah, S.M.; Haris, K.; Gokul, G.S. (IEEE, 2015)In this paper, a seafloor characterization technique to unravel the number of data classes using multibeam echo-sounding backscatter data has been demonstrated. An application of self-organizing maps (SOMs) to backscatter ... -
Buried channels provide keys to infer Quaternary stratigraphic and paleo-environmental changes: A case study from the west coast of India
Dubey, K.M.; Chaubey, A.K.; Mahale, V.; Karisiddaiah, S.M. (2019)High resolution shallow seismic data was acquired from inner continental shelf of Goa, west coast of India to map underlying stratigraphic and buried geomorphic features of shelf strata. Seismic data revealed characteristic ... -
Characterization of seafloor pockmark seepage of hydrocarbons employing fractal: A case study from the western continental margin of India
Dandapath, S.; Chakraborty, B.; Maslov, N.; Karisiddaiah, S.M.; Ghosh, D.; Fernandes, W.A.; Menezes, A.A.A. (Elsevier, 2012)A quantitative technique is applied to describe the seafloor seepages based on the multi-beam backscatter and bathymetric investigations to characterize the pockmark morphology. The variable seafloor backscatter strength ... -
Characterizing slope morphology using multifractal technique: a study from the western continental margin of India.
Chakraborty, B.; Karisiddaiah, S.M.; Menezes, A.A.A.; Haris, K.; Gokul, G.S.; Fernandes, W.A.; Kavitha, G. (Springer, 2014)Here, we present the slope configuration of the submarine gullies, ridges and the adjacent slump zone off Goa, along the western continental margin of India utilizing multibeam bathymetric and single-channel seismic data. ... -
Detection of gas-charged sediments and gas hydrate horizons along the western continental margin of India
Veerayya, M.; Karisiddaiah, S.M.; Vora, K.H.; Wagle, B.G.; Almeida, F. (Geological Society, 1998)High-resolution seismic reflection and sub-bottom profiling on the continental margin off western India has revealed the presence of characteristic acoustic maskings in the form of wipe-outs, reflector terminations and ... -
Diverse methane concentrations in anoxic brines and underlying sediments, eastern Mediterranean Sea
Karisiddaiah, S.M. (Pergamon, 2000)Elevated methane (CH sub(4)) concentrations (128-2692x10 sup(3) nM) occur in the hypersaline anoxic brine pools of Bannock and Urania Basins, eastern Mediterranean Sea, compared to low concentrations (17-80x10 sup(3) nM) ... -
Evidence for the formation of different-sized nodules by different accretionary processes
Valsangkar, A.B.; Karisiddaiah, S.M. (Taylor and Francis, 1993)Studies on different-sized polymetallic nodules from the Central Indian Ocean Basin reveal that chemical composition is largely related to the nodule diameter which show systematic decrease in Mn, Cu, and Ni content with ... -
Evidence of paleo-cold seep activity from the Bay of Bengal, offshore India
Mazumdar, A.; Dewangan, P.; Joao, H.M.; Peketi, A.; Khosla, V.R.; Kocherla, M.; Badesab, F.K.; Joshi, R.K.; Roxanne, P.; Ramamurty, P.B.; Karisiddaiah, S.M.; Patil, D.J.; Dayal, A.M.; Ramprasad, T.; Hawkesworth, C.J.; Avanzinelli, R. (American Geophysical Union, 2009)Evidence of paleo–cold seep associated activities, preserved in methane-derived carbonates in association with chemosynthetic clams (Calyptogena sp.) from a sediment core in the Krishna-Godavari basin, Bay of Bengal is ... -
Evidence of slumping/sliding in Krishna-Godavari offshore basin due to gas/fluid movements
Ramprasad, T.; Dewangan, P.; Ramana, M.V.; Mazumdar, A.; Karisiddaiah, S.M.; Ramya, E.R.; Sriram, G. (Elsevier, 2011)The Krishna-Godavari (KG) offshore basin is one of the promising petroliferous basins of the eastern continental margin of India. Drilling in this basin proved the presence of gas hydrate deposits in the shallow marine ... -
Evidences of methane-derived authigenic carbonates from the sediments of the Krishna–Godavari Basin, eastern continental margin of India
Kocherla, M.; Mazumdar, A.; Karisiddaiah, S.M.; Borole, D.V.; Rao, B.R. (Indian Academy of Sciences, 2006)Evidences of anaerobic oxidation of methane and interstitial carbonate precipitation have been recorded in sediment cores from Krishna–Godavari basin, Andhra Pradesh, India. High magnesian calcite and aragonite, typically ... -
Gas-charged sediments on the inner continental shelf off western India
Karisiddaiah, S.M.; Veerayya, M.; Vora, K.H.; Wagle, B.G. (Elsevier, 1993)High resolution seismic reflection profiles on the inner continental shelf (less than 60 m water depth) off India from 10 degrees N to 22 degrees N show 5-35 m of weakly stratified acoustically transparent clays. At water ... -
Geochemical heterogeneity along the Vema Fracture Zone, Indian Ocean: Mixing of melts from the Reunion plume and the Central Indian Ridge
Dhawaskar, P.; Ganguly, S.; Mukhopadhyay, R.; Manikyamba, C.; Iyer, S.D.; Karisiddaiah, S.M.; Mahender, K. (2020)We present here a scenario of magmatic and tectonic processes associated with the interaction between the Reunion mantle plume and the mantle beneath Central Indian Ridge (CIR) at the Vema Trench (VT) along the Vema Fracture ... -
Geochemistry, factor analysis and clay mineral distribution of the sediments and relationship with the associated ferromanganese nodules from the SW Carlsberg ridge
Valsangkar, A.B.; Karisiddaiah, S.M.; Ambre, N.V. (Indian Association for Limnology and Oceanography, 1992)Calcareous clay and ooze from the southwestern Carlberg Ridge show wide range of concentrations in Si (4.62-23.88%), Al (1.63-7.98%), Ti (0.43-1.70%) and CaCO sub(3) (8.50-79.75%) and reveal association of the elements ... -
Geodynamics of the Amirante Ridge and Trench Complex, Western Indian Ocean
Mukhopadhyay, R.; Karisiddaiah, S.M.; Ghosh, A.K. (Taylor & Francis, 2012)The formation and evolution of the approx. 600 km long arcuate Amirante Ridge and Trench Complex (ARTC) is a significant geomorphic– structural feature in the Western Indian Ocean (WIO). The WIO contains evidence of at ... -
Holocene submarine terraces on the western continental shelf of India; implications for sea-level changes
Wagle, B.G.; Vora, K.H.; Karisiddaiah, S.M.; Veerayya, M.; Almeida, F. (Elsevier, 1994)Detailed echosounding, side-scan sonar and high-resolution seismic-reflection profiling on the western continental shelf of India have revealed a series of submarine terraces at different depths between the outer fringe ... -
Methane-bearing shallow gas-charged sediments in the eastern Arabian Sea: A probable source for greenhouse gas
Karisiddaiah, S.M.; Veerayya, M. (Elsevier, 1994)