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Metallogenic Epoch and Province
Metallogenic Epoch and Province
Metallogenic Epoch and Province
Metallogenic Epoch and Province
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Metallogenic Epoch and Province

  1. Investigations have shown that metallogeny is by no means a series of isolated phenomena in the history of the evolution of the earth’s crust. It constitutes characteristic events in the evolution of mobile belts and platforms. Such mineral deposits are related in time and place to periods of crustal evolution and igneous activity that have taken place at definite periods in the earth’s history. For this period of mineralisation Lindgren used the term Metallogenetic Epochs, emphasing the timing of certain kinds of mineralisation, such as Precambrian iron-ore deposits of Bihar, Orissa and Madhya Pradesh. The areas which are characterised by preponderance of deposits of some particular type, such as gold; copper or iron, are called Metallogenetic Province. These minerals may have formed by various geological processes besides igneous activities like sedimentation, metamorphism, weathering etc The metallogenetic epochs and provinces, in the India context, are described below: ❖ Metallogenetic Epochs Metallogenetic epochs, as defined above, are specific periods characterised by formation of large number of mineral deposits. It does not mean that all the mineral deposits formed during a definite metallogenetic epochs. In India the chief metallogenetic epochs were: 1. Precambrian 2. Late Palaeozoic 3. Late Mesozoic to Early Tertiary ▪ Precambrian Epoch The Precambrian epoch is the most important the world over because of the great length of time involved and presence of large and varied mineral deposits. The huge sequence of Precambrian metasediments and associated granitoids, gneisses etc. are supposed to have a different Metallogenic history in which post consolidated events of magmatism and , metallogeny are important. The endogenic deposits have been broadly correlated to ultrabasic, basic, acid-intermediate and post-orogenic acidic phases of magmatism, while exogenic deposits, like iron and manganese, are related to sedimentary, metamorphic and other processes. This epoch in India is defined by the presence of iron-ore, chromite, manganese ore, gold, copper, lead, sillimanite, gypsum, kyanite. gemstones etc. Examples of iron-ore deposits are in: southern Singhbhum (Bihar), Keonjhar, Mayurbhanj and Sundargarh (Orissa), Bastar and Durg (Madhya Pradesh), Chanda and Ratnagiri (Maharashtra), Dharwar, Bellary, Sendur, Shimoga and Chikmangalur (Karnataka), Goa and other places; Chromite in Singhbhum (Bihar), Dhenkanal, Cuttack and Keonjhar (Orissa), Mysore and Hassan (Karnataka) and Bhandara and Ratnagiri (Maharashtra); Gold in Kolar, Hutti and Gadag (Karnataka), Ramgiri and Anantapur (Andhra Pradesh), Wynad (Tamil Nadu) and Kondrakocha (Bihar); Copper in Singhbhum (Bihar), Khetri and Pur-Banera-Bhindar (Rajasthan), Malanjkhand (Madhya Pradesh), Mailaram, Gani and Agnigundala (Ar.dhra Pradesh), Ingaldaiur and , Kalvadi (Karnataka); lead and zinc in Zawar, Rajpura Dariba, Deri, Rampur Agucha (Rajasthan), Sargipalli, Kesarpur, Karmali (Orissa), Banaskantha and Vadodara (Gujarat) and other places; and Manganese-ore in Balaghat (MP), Bhandara and Nagpur (Maharashtra), Bellary, Chitradurga, Uttar Kannad, Dharwar, Shimoga and Tumkar (Karnataka), Panch Mahal and Vadodara (Gujarat) and other places. There are many more examples of ; similar deposits. GL-Aug-2019 Economic Geology Q U A R T Z – E C I E S Nikhil V. Sherekar M.Sc. Geology 8390377801 (SET+PET+CSIR-UGC-NET-JRF AIR-28) Metallogenic Epoch & Province
  2. ▪ Permo Carboniferous (Late Palaeozoic) Epoch Towards the upper Carboniferous (Late Palaeozoic) the Hercynian: movement Introduced great changes on the surface of the globe and this is marked by mountain building and initiation of sedimentary era. In India the epoch is known by rich coal deposits of Lower Gondwana, like those of Jharia, Bokaro, Karanpura, Giridih, Ramgarh, Hutar, Daulatganj, Deoghar and Rajmahal of Bihar; Raniganj Barjora and Darjeeling of West Bengal, Singrauli, Korba, Chirimiri,- Sohagpur, Umaria, Johilia/ Bisrampur, Jhilmili etc. of MP and Godavari valley of Andhra Pradesh and at many other places. A large number of hypabyssal basic, intrusive-dolerites and basalts, and mica-rich ultrabasic rock, mica-peridotite, traverse these coal fields. Other important mineral deposits of this epoch are fireclay, iron stone and ochre, which occur within the Gondwana formation. ▪ Late Mesozoic to Early Tertiary Epoch This epoch is dominated by fissure eruptions of basalt lava flow (Deccan Trap) which now occupy over 500,000 sq.km, area in western and central India with semi-precious stones like rock crystal, amethyst, agate, carnelian, onyx and other varieties of chalcedony. Rare copper mineralisation is noted in the trap rocks. Considerable igneous activities of this epoch marked by granites, granodiorite, basic and ultrabasic rocks occur in extra peninsular regions, comprising main Himalayan ranges, Manipur-Meghalaya and Andaman Nicobar Islands. These are associated with occurrences of fluorite, copper, lead, zinc, chromite, magnesite, clay asbestos etc. in Ladakh area of Indus ophiolite belt; magnetite, nickel chromite, asbestos, magnesite and talc occurrences in Manipur-Nagaland and base metals, nickel and chromite in Andaman-Nicobar areas. ❖ Metallogenetic Provinces The metallogenetic province is known by the name of dominant and specific mineral, such as Gold Province, Copper Province, Iron-Ore Province or Manganese Ore Province. It may comprise mineralisation of more than one epoch, each superimposed upon the other, but essentially of the same type. India affords many examples of metallogenetic provinces. A few important ones are enumerated below: 1. Gold Province of Karnataka - Andhra Pradesh - Tamil Nadu (Hutti Kolar-Anantapur- Godag- Wynad Gold Province). 2. Copper Province of Singhbhum. 3. Copper Province of Khetri-Pur Banera-Bhinder. 4. Lead-Zinc Province of Hesatu-Belbathan. 5. Iron-Ore Province of Southern Singhbhum-Keonjhar-Sundargarh Mayurbhanj. 6. Iron Ore Province of Drug-Bastar-Chanda-Ratnagiri. 7. Iron Ore Province of Karnataka-Goa. 8. Manganese Province of Balaghat-Bhandara-Nagpur. • Gold Province of Karnataka-Andhra Pradesh-Tamil Nadu It covers gold fields of Kolar, Hutti and Gadag of Karnataka, Ramgiri, Gcoty, Bisanatham and Gavanikonda of Andhra Pradesh and Wynad, Cherambadi and Bensibetta of Tamil Nadu. By far the greatest part of the Province is occupied by Dharwars, represented by metamorphosed mafic volcanic rocks altered to schistose, massive, granular and fibrous amphibolites. The other rock types are muscovite-biotite-schist, quartzites and granulites, with Peninsular gneisses and granites. All these rocks and the auiferous reefs are intruded by dolerite dykes, and the final phase of igneous activity is marked by a few pegmatites. The structural metallogenic zones of the Province are characterised by mineralisations of the intermediate-late-final stages of development of the mobile belt [Au, (As, Fe, Cu, Pb, W), Pb, (Ag, Zn, Cu, Fe) and may be defined principally as : (i) Gadag-Chitaldrug-Mysore zone. (ii) Ramgiri-East Bangalore zone. (iii) Hutti-Kolar-Mamandur-Vellore-Terupati zone.
  3. The gold is associated mostly with quartz-loads of quartz-veins and sulphide bearing reefs within schist and belongs to high temperature (hypothermal) hydrothermal class. • Copper Province of Singhbhum The Copper Province of Singhbhum is localised in the shear zone, which extends from Duarpuram in the west to Barahagora in southeast for over 128 km with a width ranging upto 5 km and is moulded along the northern and the noth-eastern margin of Singhbhum granite massif. The copper ores of Singhbhum seems to be related to tongues of granite which intrude the schists. The ores occur as veins in the granite and the neighbouring mica-schists, quartz-schists, and hornblende-schist or epidiorite. These veins are well developed along a zone of overthrust, where they form well defined lodes. This province [Cu, Au, (Fe, Ni, 0)]; Pb, (Cu, Au, Fe, Zn); U, Th, Ce, (La, Pr, Nd, Sm, Be)] indicates intermediate-late final stages of development of the mobile belt. The Province represents hydrothermal and pegmatitic mineralisation in refolded synforms and dislocated antiforms of predominantly metamorphosed sedimentary of the greywacke suite are associated melavolcanics • Copper Province of Khetri-Pur-Banera-Binder There are two main zones of copper mineralisation in the Province, namely Khetri zone and Pur-Banera-Bhinder zone. They run for about 80 kin in the northeast and 135 km in the southeast part respectively of the state. The potential areas for copper are in Madhan Kudan, Kalihan and Chanmari in the Khetri zone and Dariba in Pur-Banera-Bhinder zone. Pre-Aravalli, Aravalii and Delhi groups of rocks are found in the area and the copper mineralisation are along favourable structural zones related to different orogenic movements. The Province shows, basic volcanics of the earlier stage of development of the mobile belt and an acidic magmatism of the intermediate-late stage. The mineralisation associated with earlier stage are not very predominant, while the mineralisation of the late stage have givenn rise to the following important structural Metallogenic zones; namely : (i) Singhana-Khetri-Babai zone [Cu, (Fe, As, Co)].. (ii) Anjari-Dariba-Bairat-Jadawas zone [Cu, (Fe, Ni, Co), Pb, (Zn, Sb)]. (iii ) Kishangarh-Ajitgarh-Ambamara zone [(Pb, Cu, Ti), Cu], All these zones occupy highly contorted and refolded synforms, flanked by granites and gneisses. • Lead and Zinc Province of Hesatu-Belbathan, Bihar The Province extends in WNW-ESE for about 250 km from Hesatu (Hazaribagh district) in the west to Belbathan (Godda district) in the east and has a width of about 50 km. There are over four dozen occurrences showing evidences of lead-zinc, copper mineralisation, covering the whole Province, some of the important occurrences are at Baraganda, Chandio, Jhalakdiha, Ganganpur, Damgi, Toolsitanr, Bagjrmari and other places. The mineralisation is associated mostly with Precambrian tremoliteactinolite schist, amphibolite and calc-granulite which occur as pockets within Chotanagpur granite-gneisses. • Iron Ore Province of South Singhbhum-Keonjhar-Sundargarh - Mayurbhanj About 15 to 20 million tonnr.es of annual Iron-Ore production is from this Province. Deformed and folded belts of Precambrian metasediments (flysch and volcanics) along with gneisses and granites of at least two generations (Chotanagpur gneiss and Singhbhum granite) cover a major part of the area and indicate the development of interior areas of a mobile belt. The Province embraces iron-ore deposits of Noamundi, Notoburu, * ' Jamda, Gua, Jhilingburu and Pansiraouda and others of $outh Singhbhum Bihar) and Thakurani, Rolana. Joda , Malanteli etc. of Keonjhar, Baliapahar, Barsua, Bonai etc. of Sundargarh, Gorumahisani, Salaipat, Badampahar and Simlipal hill of Mayurbhanj; Daitari, Tamka and Kansa of Cuttack, and Hirapur and llmarkot of Koraput (Orissa). The banded Iron-Ore formation with very good hematite iron-deposits are found. The important structural metallic zones delineated in the area are given below :
  4. ( i ) Cuttack-Keonjhar-Singhbhum-Mayurbhanj Zone [Cr, (Fe, Ni, Co); Fe, (Va, Ti); Pb] (ii ) Singhbhum-Keonjhar zone (Fe, Mn) (iii ) Mayurbhanj-Sarnbalpur-Koraput-Sundargarh zone (Fe, Mn) The above are structural Metallogenic zones of the sedimentary metamorphic deposits of iron and manganese. Titano-vanadiferous iron ore type, recognised in south-east Singhbhum and Mayurbhanj is classed as liquid magmatic deposit and have formed during early crystallization of basic plutonic rocks. • Iron-Ore Province of Chanda-Drug-Bastar This iron-ore Province embraces important iron-ore deposits of Lohara, Pipalgaon, A.sola and Dewalgaon (Chanda district); Dhalli and Rajhara (Drug); and Rawghat, Parrekaro and Bailadila (Bastar district) and produces about 12 to 15 million tonnes ore annually! This represents metamorphosed flysch type of association with exogenic mineralisation m Banded-Hematite-Quartzite of the early stage of development of mobile belt. The following structural metallogenic zones have been recognised in the Province : (i ) Pipalgaon-Lohara-Asola-Dewalgaon zone. (ii) Dhalli-Rajhara-ParrerkaO zone. (iii) Bailadila-Kandpai-Parotwada-Taki zone. • Iron-Ore Province of Karnataka-Goa This is another iron-ore province which produces altogether 46% of Indian production i.e. annually about 25 million tonnes of iron-ore. This represents structural metallogenic zones of sedimentary metamorphic deposits, considered to be corresponding to the early stage of development of mobile bells - iron-ores in greywacke association Banded iron-ore formation with good hematite iron-ore deposits is prevalent Magnetite rron-ore (Titano- venadiferous) is found in Tumkur district and may be classed as magmatic deposit, formed during early crystallisation of basic plutonic rocks. Bellary-Hospet, Shimoga, Chitradurga, Chikmaglur, Kudramukh and Bababudan hills are the important iron-ore deposits found in the Province. • Manganese Province of Balaghat-Bhandara-Nagpur This Province falls in Madhya Pradesh and Maharashtra states and together produces about 40 per cent of manganese-ore annually out of total Indian output. They represent Gondite type of deposits associated with metamorphosed Dharwar rocks which are characterised by predominantly quartzite-carbonate associations with subordinate gneisses and granites of at least two generations. The exogenic deposits of Mn in the Province are associated with an early phase of sedimentation and as such may also be largely pre-orogenic.
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