Browsing by Author "Iyer, S.D."
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A comprehensive view of manganese nodules and volcanics of the Central Indian Ocean Basin
Jauhari, P.; Iyer, S.D. (Taylor & Francis, 2008)The Central Indian Ocean Basin (CIOB) is the most studied basin in the Indian Ocean because of the Indian Manganese Nodules program. During the last two and half decades (and also on going), immense efforts have been made ... -
A new report of serpentinites from Northern Central Indian Ridge (at 6 degrees S) - An implication for hydrothermal activity
Ray, Dwijesh; Banerjee, R.; Iyer, S.D.; Mukhopadhyay, S. (Geological Society of China, 2008)Abstract: Serpentinites from the inside corner high (6O38.5'SI 6S019.34'E) from the Northern Central Indian Ridge (NCIR) are comprised mainly of high Mg-rich lizardite and chrysotile pseudomorphs with varying morphologies. ... -
A new report on the occurrence of zeolitites in the abyssal depths of the Central Indian Basin
Iyer, S.D.; Sudhakar, M. (Society for Sedimentary Geology, 1993)Forty-two indurated slabs of zeolites collected from the abyssal depths of the Central Indian Basin have been studied. The slabs show characters similar to harmotome-rich scorias of the Society Ridge and phillipsite slabs ... -
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 sulphide-oxide mineralisation in Carlsberg Ridge basalts
Banerjee, R.; Iyer, S.D. (Geological Society of India, 1993)Pillow basalts from the Carlsberg Ridge at 3 degrees 35'N contain disseminated chalcopyrite, pyrite, and magnetite. The euhedral shape of the pyrite grains indicate them to be early formed and grown unobstructed while ... -
A petrogenetic model of basalts from the Northern Central Indian Ridge: 3-11°S
Ray, Dwijesh; Iyer, S.D.; Banerjee, R.; Misra, S.; Widdowson, M. (Geological Society of China, 2007)Mid-Ocean Ridge Basalts (MORB) from Northern Central Indian Ridge (NCIR) were recovered between latitudes 30 and 110S and are olivine tholeiite with higher abundances of K and Rb. They are of typical transitional MORB ... -
Alteration of basaltic glasses from the Central Indian Ocean
Iyer, S.D. (Geological Society of India, 1999)Textural, mineralogical and compositional characteristics of basaltic glasses from the Central Indian Ocean show them to be altered to varying extents through their interaction with the seawater, resulting in the formation ... -
Basalt microlapilli in deep sea sediments of Indian Ocean in the vicinity of Vityaz fracture zone
Nath, B.N.; Iyer, S.D. (Geological Society of India, 1989)Two cores recovered from the flanks of Mid-India oceanic ridge in the vicinity of Vityaz fracture zone consist of discrete pyroclastic layers at various depths. These layers are composed of coarse-grained, angular basaltic ... -
Beach dynamics and oscillations of shoreline position in recent years at Miramar Beach, Goa, India: a study from a GPR survey.
Loveson, V.J.; Gujar, A.R.; Iyer, S.D.; Udayaganesan, P.; Luis, R.A.A.; Gaonkar, S.S.; Chithrabhanu, P.; Tirodkar, G.; Singhvi, A.K. (Springer, 2014)Consideration of human influences is crucial to understanding the coastal sediment supply and associated shoreline responses prior to undertaking coastal hazard management studies. Observation of the widening of some ... -
Biogenic influence on the growth of ferromanganese micronodules in the Central Indian Ocean
Banerjee, R.; Iyer, S.D. (Elsevier, 1991)In a 20 cm core collected from the Central Indian Basin, with increasing depth, the abundance of ferromanganese micronodules decreases as their size increases, and the surface texture changes from rough to smooth. Biological ... -
Buried nodules and associated sediments from the central Indian Basin
Banerjee, R.; Iyer, S.D.; Dutta, P. (Springer, 1991)Buried nodules from siliceous sediments in the central Indian Basin are morphologically variable and mineralogically consist of d-MnO2 incipient todorokite. Compositionally they are weakly diagenetic. The sediment coarse ... -
Characteristics and genesis of phillipsite grains in a sediment core from the Central Indian Ocean Basin
Iyer, S.D.; Pinto, S.M.; Sardar, A.A. (2018)Present study is the phillipsite grains present in a siliceous sediment core (water depth 5100 m) recovered near a seamount from the Central Indian Ocean Basin (CIOB). Phillipsite occurs as single grains, cruciform crystals ... -
Coarse fraction components in a red-clay sedimemt core, Central Indian Ocean Basin: Their occurrence and significance
Iyer, S.D.; Fernandes, G.Q.; Mahender, K. (Indian Association of Sedimentologists, 2012)Coarse Fractions Components of a sediment core (268 cm from a water depth of 5120 m) collected at 18 degrees S and 80 degrees E from the red clay domain in the Central Indian Ocean Basin (CIOB), comprises mineral grains, ... -
Coastal placer minerals
Iyer, S.D.; Gujar, A.R. (NISCAIR Publications, 2014)India is blessed with a long coastline of more than 7500 km, including islands. The erosion of rocks results in coastal placer minerals, which find many applications. -
Coexistence of pumice and manganese nodule fields-evidence for submarine silicic volcanism in the Central Indian Basin
Iyer, S.D.; Sudhakar, M. (Pergamon, 1993)Pumice, of various shapes and sizes, uncoated or coatEd. by ferromanganese oxides, have been recovered from deeper parts of the Central Indian Basin (CIB). The pumice field covers an area of 600,000 km sup(2), approximately ... -
Comparison of internal features and microchemistry of ferromanganese crusts from the Central Indian Basin
Iyer, S.D. (Springer, 1991)SEM/probe analyses of two ferromanganese crusts from the Central Indian Basin, formed on basalt substrate, reveal botryoids and cusps. The botryoids composed of delta-MnOs2, are enriched in Co, and the cusps and laminations ... -
Composition and genesis of zeolitic claystones from the central Indian Ocean Basin
Iyer, S.D.; Sudhakar, M.; Das, P. (Geological Society of China, 2007)More than fifty indurated sediments recovered from the Central Indian Ocean Basin (CIoB) are examined during the course of collection for manganese nodules and crusts. The samples occur as slabs either over which ferromanganese ... -
Correlation between occurrence of manganese nodules and rocks in a part of the Central Indian Ocean Basin
Iyer, S.D.; Sharma, R. (Elsevier, 1990) -
Depositional environments inferred from variations of calcium carbonate, organic carbon, and sulfide sulfur: a core from southeastern Arabian Sea
Paropkari, A.L.; Iyer, S.D.; Chauhan, O.S.; PrakashBabu, C. (Springer, 1991)The variations in CaCO3 and organic carbon and their inter-relationship in a core from the southeastern Arabian Sea (water depth 2,212 m) have been used to demarcate the Holocene/Pleistocene boundary; an increased terrigenous ... -
Distribution and origin of seamounts in the central Indian Ocean Basin
Das, P.; Iyer, S.D.; Kodagali, V.N.; Krishna, K.S. (Taylor and Francis, 2005)Approximately 200 seamounts of different dimensions have been identified, from multibeam bathymetry maps of the Central Indian Ocean Basin (CIOB) (9 degrees S to 16 degrees S and 72 degrees E to 80 degrees E), of which 61% ...