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Deb, M.
- Some Observations on the Mineralogy and Metamorphism of the ZN-PB-CU Ores from Deri-Ambaji Area, Banaskantha District, Gujarat
Authors
1 Department of Geology, University of Delhi, Delhi, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 14, No 4 (1973), Pagination: 419-423Abstract
No Abstract.Full Text
- Study of Lead Isotopes for Investigating the Origin of Endogenic Deposits with Special Reference to Some Ore Deposits from India
Authors
1 Institute of Geology of Ore Deposits (IGEM) Academy of Sciences, 35, Staromonetnii Street, Moscow, USSR, RU
2 Chitradurga Copper Co., IN
3 Mineralogical Inst., University of Mysore, Manasa Gangotri, Mysore 6, IN
4 Dept. of Geology, University of Delhi, Delhi 7, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 21, No 3 (1980), Pagination: 107-116Abstract
The isotope composition of leads from ore deposits in general reflects the age of ore mineralisation and its genetical features. Two examples have been given to illustrate a direct connection of ore lead isotope composition with the source ore. Calculations of the model age from lead isotope data form the basis for genetic reconstructions of Precambrian deposits. Radical improvement in the accuracy of mass spectrometric isotope lead analysis has made possible the employment of two-stage and in some cases more complicated models for genetic reconstructions. The Penehanga Bay lead-zinc deposit and gold-silver deposits of South Dakota have been studied using high accuracy mass spectrometer. Both the deposits show that ore formation took place one to two billion years after craton formation, and lead present in ores originated at least from two different Sources.
Keeping this background of experience, fifteen galena samples from five sulphide and gold-sulphide deposits of the Indian Shield have been selected and determination of lead isotope composition has been carried out by the Soviet authors in the USSR using recently developed M.I.1320 Mass Spectrometer. The isotopic ratios of galena from Ingaldhal copper deposit are the most primitive among the analysed ores of the Indian Shield. The results of lead isotopic determination have been interpreted in terms of the general theory of 'plumbotectonics '.
- Rare Minerals in Rajpura-Dariba Ores-Some Further Comments
Authors
1 Department of Geology, University of Delhi, Delhi 110 007, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 23, No 5 (1982), Pagination: 253-260Abstract
Thirteen rare sulfides, sulfo-salts and native metals: geocronite, owyheeite, bournonite, polybasite/pearceite, native arsenic, enargite, electrum, aurostibite, pyrargyrite, argentite, argentopyrite, gudmundite, stannite (?l) have been identified in the Rajpura-Dariba ores on the basis of their optical properties including quantitative spectral reflectance. The localisation of these rare minerals in remobilised veins of massive chalcopyrite or galena-tenantite along with their crystallisation history suggests that most of the rare minerals formed by mobilization of the metals involved during regional metamorphism under amphibolite facies conditions.- Geochemical Studies of Soil, Bedrock and Stream Sediment Around Base Metal Mineralization in Tiranga Hill, Bhilwara District, Rajasthan, India
Authors
1 Department of Geology, University of Delhi, Delhi-110 007, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 28, No 6 (1986), Pagination: 431-441Abstract
The Tiranga Hill is located in the southernmost part of the 25 km long Pur-Banera mineralized belt in the Bhilwara District of Rajasthan. Exploration by Government agencies has revealed low grade Pb-Zn-Cu sulfide mineralization along this Early to Middle Proterozoic metasediments and meta-volcanics, regionally metamorphosed to amphibolite facies. At Tiranga, the mineralization occurs within a metamorphosed banded iron-formation spatially associated with spectacularly-folded banded magnetite quartzite (BMQ) bands.
The soils, neglecting the effects of ancient workings, are highly anomalous in Pb and Zn and also to certain extent in Cu. The major anomalies coincide spatially with the cores of synformal folds in BMQ bands, suggesting structural control of the richer parts of the mineralization. The Tiranga soils display strong interelemental correlations between Cu, Pb, Zn, Ag, Fe and Mn, The base metals display similar dispersal behaviour in soils and stream sediments. Their relative mobility in the weathering zones of Tiranga Hill is : Zn >Cu >Pb. Somewhat surprising, however, is the lower concentration of Fe and Mn as well as Ni and Cr in the soils compared to the bedrock.
- Proterozoic Mafic Volcanism in the Aravalli-Delhi Orogen, North-western India: Geochemistry and Tectonic Framework
Authors
1 Department of Geology, University of Delhi, Delhi - 110 007, IN
2 Department of Geology, University of Leicester, Leicester LE1 7RH, GB
3 Department of Geology, Aligarh Muslim University, Aligarh - 202 001, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 72, No Spl Iss 1 (2008), Pagination: 93-111Abstract
The Aravalli-Delhi orogen in Rajasthan and northern Gujarat, NW India, hosts extensive bodies of mafic metavolcanic rocks within the Archaean Banded Gneissic Complex (BGC) basement and in the Proterozoic supracrustal belts of Bhilwara, Aravalli, Jharol and Delhi. There is no significant occurrence of mafic dykes in these terrains. All metavolcanic rocks within the supracrustal belts show typical tholeiitic compositions except for the samples from the Basantgarh area of the Delhi belt, which show calc-alkaline nature. The Bhilwara belt and Aravalli belt samples show light rare earth elements (LREE) enrichment, the Jharol belt samples are predominantly LREE depleted, whereas the Delhi belt samples show wide variations from slightly depleted through flat to highly fractionated REE patterns. Multi-element patterns are consistent with the REE patterns in terms of enrichment or depletion for the large ion lithophile elements (LILE) and with respect to high field strength elements (HFSE). The incompatible trace elements ratios (e.g. Nb/Zr, Y/Zr, Ce/Nd, etc.) are similar for the metavolcanic rocks of the Bhilwara and Aravalli belts. Samples from the Jharol and Delhi belts differ amongst themselves as well as with those from the Bhilwara and Aravalli belts. The Delhi belt samples show large variations in incompatible trace element ratios. Comparison of multi-element patterns for the volcanic rocks from the Aravalli-Delhi orogen with those from various modern tectonic settings, potentially allows constraining their tectonic setting of eruption. The tholeiitic metavolcanic rocks of the Bhilwara belt erupted along the incipient divergent eastern margin of the Archaean BGC continent and the basal Aravalli and Jharol metavolcanic rocks along its rifted western margin. The Delhi belt metavolcanic rocks indicate the evolution of the Delhi island arc through eastward subduction and emplacement of the Basantgarh-Ajari and Ranakpur-Desuri metavolcanic rocks close to the Phulad-Jetgarh suture zone on the western fringe of the arc and those of the Ambaji-Deri region along back arc spreading zones to the east, where protracted rifting led to the emplacement of gabbro-syenite plutons.Keywords
Geochemistry, Mafic Volcanism, Tectonics, Proterozoic, Delhi-Aravalli Orogen.- Breithauptite: A Rare Antimonide in the Dariba-Rajpura-Bethumni Belt, Rajsamand District, Rajasthan
Authors
1 Department of Geology, University of Delhi, Delhi - 110 007, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 74, No 1 (2009), Pagination: 35-38Abstract
Breithauptite (NiSb), a rare antimonide, is generally found associated with hydrothermal vein ores of Ni and Co. In India, it has so far been recorded only from the gold-quartz veins of the Kolar Gold Field. Occurrence of this antimonide in a sediment-hosted milieu however, has seldom been noted. We report here the identification and characterization of this rare phase in both the stratiform and the vein-type ores of the sediment-hosted Zn-Pb sulphide deposits and prospects within the Dariba-Rajpura-Bethumni metallogenic belt in Northwestern India. Metamorphic remobilization from the stratiform ores of the belt has been postulated as a possible mechanism for the conspicuous segregation of breithauptite as a discrete phase within these ores.Keywords
Antimonide, Breithauptite, Dariba-Rajpura-Bethumni Belt, Metamorphic Remobilization, Rajasthan.References
- COOK, N.J. (1996) Mineralogy of the sulphide deposits at Sulitjelma, Northern Norway. Ore Geology Reviews, v.11, pp.303-338.
- DEB, M. and PAL, T. (2004) Geology and Genesis of the base metal sulphide deposits in the Dariba- Rajpura-Bethumni belt, Rajasthan, India, in the light of basin evolution. In: M. Deb and W.D. Goodfellow (Eds.), Sediment-hosted lead-zinc sulfide deposits with emphasis on the deposits in the northwestern Indian shield: Narosa Publishing House, New Delhi, pp.304-327.
- DEB, M. (1982) Rare minerals in Rajpura-Dariba ores - some further comments: Jour. Geol. Soc. India, v.23(5), pp.253-260.
- GEMMELL, J. B., ZANTOP, H. and MEINERT, L. D. (1992) Genesis of the Aguilar zinc-lead-silver deposit, Argentina; contact metasomatic vs. sedimentary exhalative. Econ. Geol., v.87, pp.2085-2112.
- HALDAR, S.K. (2004) Grade and Tonnage Relationships in Sediment-hosted Pb-Zn Sulphide Deposits of Rajasthan, India. In: M. Deb and W.D. Goodfellow (Eds.), Sediment-hosted lead-zinc sulfide deposits with emphasis on the deposits in the northwestern Indian shield: Narosa Publishing House, New Delhi, pp.264-272.
- HEWITT, D.F. (1992) A partial study of the NiAs-NiSb system. Econ. Geol., v.43 pp.408-417.
- MINERAL DATA PUBLISHING (2001) http://www.handbookof mineralogy.org/pdfs/breithauptite.pdf
- RAGHU NANDAN, K.R., DHRUVA RAO, B.K. and SINGHAL, M.L. (1981) Exploration for Copper Lead and Zinc Ores in India. Bull. Geol. Sur. India, Series A, Econ. Geol., v.47, pp.125-128.
- RAMDOHR, P. (1969) The ore minerals and their intergrowths. Pergamon Press, 1174p.
- UYTENBOGAARDT, W. and BURKE, E.A.J. (1973) Tables for microscopic identification of ore minerals. Elsevier, Amsterdam, 430p.
- Mineralisation in the Western Indian Craton
Authors
1 New Delhi, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 49, No 5 (1997), Pagination: 603-603Abstract
No Abstract.Full Text