- K. V. Subbarao
- V. V. Reddy
- G. R. Reddy
- R. N. Sukheswala
- R. Hekinian
- A. V. Murali
- P. B. Pawaskar
- V. N. Vasudev
- M. Sankar Das
- P. K. Seccombe
- J. N. Pawar
- M. Sreenivasa Rao
- N. Ramasubba Reddy
- C. V. R. K. Prasad
- C. Radhakrishnamurty
- S. Pathak
- M. J. Le Bas
- B. Bhaskar Rao
- R. Shankar
- V. Kolla
- M. R. Goutham
- K. Raghubabu
- V. Damodara Reddy
- Arun Agarwal
- chaitan Baru
- S. Viswanadhan
- Richa Sahu
- Anil Kumar
- J. N. Walsh
- T. K. Biswal
- R. Vaidyanadhan
- B. B. G. Sharma
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
SubbaRao, K. V.
- Rare Earth Element Geochemistry of Basalt-Spilite Association of Bombay and Carlsberg Ridge-A Preliminary Study
Authors
1 Indian Insntute of Technology, Powai, Bombay-400076, IN
2 Bhabha Atomic Research Center, Trombay, Bombay-400085, IN
3 St. Xavier's College, Bombay-400 001, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 20, No 10 (1979), Pagination: 517-519Abstract
No Abstract.- Rare Earth Geochemistry of Basalts from the 'FAMOUS' Area Mid-Atlantic Rift Valley-A Preliminary Study
Authors
1 Indian Institute of Technology, Powai, Bombay-400076, IN
2 Bhabha Atomic Research Centre, Trombay, Bombay-400085, IN
3 Centre Oceanologique de Bretagne, 29-273 Brest, FR
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 20, No 11 (1979), Pagination: 565-569Abstract
Rare earth element (REE) analysis for fresh glass and crystalline basalts from the FAMOUS area along the Rift Valley at about 36°N in Atlantic Ocean lying close to the triple junction of North American, Eurasian and African plates, are presented. These rocks display light rare earth element (LREE) patterns with (La/Sm)e.f. ratios ranging between 0.56-0.84 similar to spreading mid-oceanic ridge rocks, suggesting the definite presence of large ion lithophile element (LILE) depleted mantle source in this area. White and Bryan (1977) report the presence of LREE enriched basalts from the FAMOUS area which perhaps resulted due to the effect of the Azores mantle plume. Thus, geochemically the FAMOUS area represents a transitional zone-a mixture of mantle plume and LILE depleted normal ridge.- Petrogenetic Significance of Rare Earth Element Patterns of Selected Samples of Ingaldhal Metavolcanics, Karnataka State, India: Consortium Studies No.1
Authors
1 Analytical Chemistry Division, Bhabha Atomic Research Centre, Trombay, Bombay-400085, IN
2 Geology Department, Indian lnstitute of Technology, Powai, Bombay-400 076, IN
3 Chitradurga Copper Company, 16, Ali Asker Road, Bangalore-560052, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 20, No 7 (1979), Pagination: 334-338Abstract
No Abstract.- Sulphur Isotopic Composition of Ingaldhal Sulphides, Karnataka State, India
Authors
1 Department of Geology, University of Newcastle, Newcastle, N. S. W. 2308, AU
2 Indian Institute of Technology, Powai, Bombay 400076, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 22, No 7 (1981), Pagination: 326-330Abstract
Mineralisation at Ingaldhal, Kamataka State, comprises massive vein and disseminated sulphides within deformed Archaean metasedimentary rocks and metabasaltic rocks of tholeiitic affinity. Seven sulphur isotope ratio determinations on sulphide minerals separated from ore samples yield a narrow distribution of δ34S values around the meteoritic mean (range -0.9 to +0.4 per mil; mean -0.2 per mil) values which arc similar to Archaean volcanogenic ores elsewhere.The source of sulphur is considered to be magmatic, with possible contribution from Archaean seawater. The stockwork and massive nature of the Ingaldhal ores, their Cu-Fe content, poorly developed metal zoning and basic volcanic association in a submarine setting point strongly to subsurface and sea-floor sulphide accumulation from sulphur- and metal-bearing fluids of volcanic origin. The sulphur isotope data support this view.
- Tephra Studies
Authors
1 I.I.T., Bombay, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 24, No 9 (1983), Pagination: 484-486Abstract
No Abstract.- Chemical and Magnetic Stratigraphy of Parts of Narmada Region, Deccan Basalt Province
Authors
1 Department of Earth Sciences, Indian Institute of Technology, Bombay 400076, IN
2 Department of Geology, Sri Venkateswara University, Tirupati 517502, IN
3 Tata Institute of Fundamental Research, Bombay 400005, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 26, No 9 (1985), Pagination: 617-639Abstract
Field investigations of a 666 m thick Deccan volcanic sequence north of the River Narmada (Khalghat-Mhow traverse; 60 km) showed the presence of 21 flows, while a 549 m thick southern section comprises of 28 flows (Mandaleswar-Pipaljopa traverse: 110 km). The lava sequences essentially consist of PI and/or Pyx phyric to aphyric basalts with glassy vesicular - amygdular tops/flow breccia.
On the basis of selected major and trace elements (Si, K, Ti, P, Ba, Sr, Zr), the Khalghat section is divided into three formations. The lowermost Narmada Formation is characterized by lower K, Ba, Sr, Ba/Ti, Ba/Sr and Ba/Zr than the succeeding Manpur Formation. The uppermost Mhow Formation is highly depleted in K, Ba, Sr compared to the two lower formations. Chemically, a four-unit informal stratigraphy has been adopted for the Mandaleswar section. The lower three may be correlated with the Narmada, Manpur and Mhow Fms of the Khalghat section and the upper one is labelled the Satpura Formation. Each formation is defined as a set of flows characterized by one or more chemical types such as 'primitive' and' evolved' ones.
The palaeomagnetic results of the Khalghat section demonstrate that the lower 254m pile of flows belongs to normal polarity (N) ('Narmada Normal Epoch') overlain by 412 m thick flows with reversed polarity (R) ('Malwa Reversed Epoch'). Interestingly, on the southern side of the river, about 21 m thick N flows are overlain by 476 m R flows, which in turn are capped by 52m thick N flows ('Satpura Normal Epoch') resulting in an unambiguous NRN sequence in the Deccan basalt province. It appears that the northern side of the Narmada River has been thrown up relative to the southern side. Based on the correlation of the magnetic reversals in the Deccan as well as marine magnetic anomalies, it seems likely that the normally magnetized older Rajmahal traps (about 100 MA) of eastern India form the base of the Deccan basalts.
- Reversely Magnetized Flows, Rajahmundry, Andhra Pradesh
Authors
1 Department of Earth Sciences, Indian Institute of Technology, Powai, Bombay-400 076, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 41, No 1 (1993), Pagination: 71-72Abstract
No Abstract.- Petrographic and Magnetic Studies of a Columnar Sill and a Dyke from the Deccan Traps
Authors
1 Dept. of Earth Sciences, Indian Institute of Technology, Powai, Bombay 400 076, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 42, No 1 (1993), Pagination: 83-94Abstract
A critical petrographic investigation together with magnetic studies such as the variation of susceptibility with temperature and hysteresis have been carried out on basalt samples drilled across a dyke and a columnar sill from the Deccan Traps. In the case of columnar basalts, not much variation has been found in the grain size but display increase in shattering of the grains towards the edge of the column. In contrast, the dyke samples are tachylitic at the edge grading to fine-grained basalt in the middle.The magnetic hysteresis studies indicate an increase of single-domain (SO) mineral grains from the margin to the centre of the columnar basalt. Low temperature susceptibility studies clearly indicate Ihe presence of some multidomain (MD) componcnt of pure magnctite in the cdge samples where as it is barely noticeahle in the s.1l1lple from the cenlre. Samples from the dyke show systematic variations of rhe magnetic parameters. These magnetic variations can be undcrstood in terms of titanomagnctite composition and domain states of thc grains among samples from across the dyke.
Keywords
Deccan Traps, Dyke, Sill; Petrology, Maharashtra.- Are the Vinjamur Rocks Carbonatites or Meta-Limestones?
Authors
1 Department of Earth Sciences, Indian Institute of Technology, Powai, Bombay 400 076, IN
2 Department of Geology, University of Leicester, Leicester LEI 7RH, GB
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 46, No 2 (1995), Pagination: 125-137Abstract
New whole-rock rare earth element (REE) data for the metacarbonate rocks interbedded with schists at Vinjamur in the Nellore Schist Belt of Andhra Pradesh, show low total REE contents (Σ9-128 ppm) that are inconsistent with an igneous carbonatitic origin but which correspond more closely with a sedimentary limestone origin. The REE data of these rocks however, do not give absolute discrimination between marbles of meta-limestone and metacarbonatite origin. Micro-probe analytical data give better discrimination, and the chemical compositions of the calcite, micas, amphibole, plagioclase, apatite, monazite and staurolite in the Vinjamur marbles give strong and consistent evidence of a metamorphosed sedimentary rather than an igneous origin.Keywords
Carbonatites, Vinjamur, Nellore Schist Belt, Andhra Pradesh.- Magnetic Susceptibility Stuldies of Surficial Sediments from the Deep Arabian Sea
Authors
1 Department of Marine Geology, Mangalore University, Mangalagangotri 574 199, IN
2 Department of Earth Sciences, Indian Institute of Technology, Powai, Bombay 400 076,, IN
3 ELF Aquitaine Petroleum, 1000 Louisiana, Houston, Texas 77002, US
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 43, No 2 (1994), Pagination: 159-167Abstract
A wide variety of processes such as volcanic activity, submarine and continental weathering, aeolian transport and authigenesis can account for the magnetic susceptibility of the deep Arabian Sea sediments. Preliminary studies of the magnetic fraction indicate that it is predominantly composed of pseudo-single domain and viscous magnetite. It is found that magnetic susceptibility can be used to estimate the approximate iron content of marine sediments.Keywords
Magnetic Susceptibility, Marine Geology, Arabian Sea.- A Neoproterozoic Geomagnetic Field Reversal from the Kurnool Group, India: Implications for Stratigraphic Correlation and Formation of Gondwana
Authors
1 Department of Geophysics, Osmania University, Hyderabad - 500 007, IN
2 Department of Geology, Sri Venkateswara University, Tirupati - 517 502, IN
3 "Amararama" Venkataratnam Street, Suryaraopet, Vijayawada - 520 002, IN
4 Centre for Earth and Space Sciences, University of Hyderabad, Hyderabad - 500 046, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 67, No 2 (2006), Pagination: 221-233Abstract
The Proterozoic Cuddapah Supergroup is predominantly of normal magnetization but has a reversely magnetized level coinciding with the Srisailam Quartzite at the top of the succession. The Kurnool Group overlies the Cuddapah Supergroup with an unconformity and we present palaeomagnetic results from the Kurnool Group members comprising the Banganapalli Quartzite and the Narji Limestone. The Neoproterozoic Banganapalli Quartzite carries stable normal and reverse magnetizations suggesting a geomagnetic field reversal at the time of its formation. The Narji Limestone is normally magnetized. A similar magnetization to that in the Banganapalli Quartzite is reported -1000km away in the Baghain Sandstone of the Vindhyan Supergroup. A possible correlation is made between Cuddapah Supergroup and Kurnool Group with the Vindhyan Supergroup. Based on palaeomagnetic poles, palaeolatitudes, palaeoclimatic and structural evidence it is suggested that India and Australia collided possibly during Neo-Proterozoic times in an attempt to form larger Gondwana.Keywords
Palaeomagnetism, Reversal of Poles, Magnetostratigraphy, Gondwana Evolution, Cuddapah Supergroup, Kurnool Group, Andhra Pradesh.- Workshop on Cyberinfrastructure for the Geosciences
Authors
1 University of Hyderabad, Hyderabad - 500 046, IN
2 University of California, San Diego 9500 Gilman Drive, MC 0505 La Jolla, CA - 92093, US
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 67, No Spl Iss 5 (2006), Pagination: 700-701Abstract
No Abstract.- An Action Plan for Preparedness and Mitigation of Damage and Destruction Due to Tsunamis
Authors
1 Centre for Earth and Space Sciences University of Hyderabad, Gachibowli, Hyderabad - 500 046, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 65, No 3 (2005), Pagination: 367-368Abstract
No Abstract.- The Journey of the Deccan through the Indian Ocean
Authors
1 Indian Institute of Technology, Mumbai and University of Hyderabad, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 65, No 2 (2005), Pagination: 256-257Abstract
No Abstract.- Geothermal Energy Resources of India
Authors
1 IIT, Bombay, Powai Mumbai - 400 076, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 61, No 5 (2003), Pagination: 634-634Abstract
No Abstract.- Rb-Sr Age and Sr Isotopic Composition of Alkaline Dykes near Mumbai: Further Evidence for the Deccan Trap-Reunion Plume Connection
Authors
1 Indian Institute of Technology, Mumbai - 400 076., IN
2 National Geophysical ,Research Laboratory, Hyderabad - 500 007., IN
3 Royal Holloway, University of London, Egham, Surrey TW20 OEX, GB
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 62, No 5 (2003), Pagination: 641-646Abstract
No Abstract.- Professor C. Radhakrishnamurty (1933-2001)
Authors
1 Indian Institute of Technology, Mumbai, IN