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Sikka, Deshbandhu
- Malanjkhand: Proterozoic Porphyry Copper Deposit, M.P. India
Authors
1 2108,3463 RUE STE Famille Montreal H2X 2K7, CA
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 34, No 5 (1989), Pagination: 487-504Abstract
The Malanjkhand porphyry copper deposit is estimated to contain 789 million tonnes averaging 0.83% Cu @ cut-off-grade of 0.20% Cu, 0.004wt% Mo, 0.2 gm/T Au, 6 gm/T Ag. 448 million tonnes 0.84% Cu (millhead grade) are available for open pit mining to a depth of 100 MRL. The deposit can support a mine, mill, smelter and refinery complex to produce 100,000 TPY of cathode copper at an installed cost of US$557.126 millions.
The deposit is arcuate in shape, 2,600 meter long, 142 meter wide, 900 meter deep and open for exploration at depth across and along strike. The deposit consists of a large body of primary copper ore in granitic rocks and is overlain by a cap of oxidized ore (7.532 million tonnes 0.8 wt % Cu). The granitic rocks are biotite granite, quartz diorite, granodiorite and adamellite (quartz monzonite). The granitic rocks are 1684±67m.y. and 1816±73m.y., (Middle Proterozoic age). Hypogene alteration includes sericitization, saussuritization, chloritization, propylitization, silicification, potassic and sodic alterations. The main primary copper mineral is chalcopyrite. The secondary copper minerals are a number of copper sulfides, sulfates, carbonates, oxides, native copper and chlorides.
- Review of Precambrian Porphyry Cu ± Mo ± Au Deposits With Special Reference to Malanjkhand Porphyry Copper Deposit, Madhya Pradesh, India
Authors
1 Cabinet-Conseil En Geologie Miniere Sikka ENR. 2108, 3463 Rue Ste Famille, Montreal, H2X 2K7, CA
2 Department of Geology, Brooklyn College, City University of New York, Brooklyn, NY 11210, US
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 49, No 3 (1997), Pagination: 239-288Abstract
Precambrian porphyry type Cu±Mo±Au deposits are present in many parts of the world including Australia, Brazil, Canada, China, Finland, India, Namibia, Russia, Sweden, and Zambia. Most of them are associated with calc-alkaline or alkaline subduction zone volcanics or granitoids of the I-type. Precambrian deposits range in age from 33l4±6 Ma to 561±9 Ma. The majority of the deposits fall into four age groupings with peaks around 3300±100Ma, 2700±100Ma, 1900±100 Ma. and 1100 ± 100 Ma which are indicative of major tectonic and magmatic episodes in different parts of the world. Precambrian deposits have many similarities with the younger porphyry copper deposits in the Phanerozoic. Some outstanding examples include Malanjkhand deposit (789 Mt x 0.83% Cu; 0.004% Mo: 0.2 gm/T Au; 6 gm/T Ag) and Tongkuangyu, China (380 Mt x 0.67% Cu) are in production. The Troilus Lake deposit, Quebec, Canada (42.9 Mt x 0.12% Cu; 1.4 gm/t Au; 1.4 gm/ t Ag) and Haib River, Namibia (600 Mt x 0.3% Cu) are being considered for exploitation.
After a review of the salient features of porphyry Cu±Mo±Au deposits in general and those of the Precambrian porphyry Cu±Mo±Au age in particular, it is suggested that Precambrian terrains should be good targets for exploration.