Mining Geology Questions and Answers

Answer: A

The association diagnostic of the highly oxidized zone is smithsonite, malachite, anglesite.

Above the water table, oxygenated water breaks down the primary sulphides of a base metal vein, and zinc, copper and lead are re-deposited as oxidized minerals: smithsonite (ZnCO₃), malachite (Cu₂CO₃(OH)₂) and anglesite (PbSO₄). All three are secondary oxidation products of the very metals a base metal vein carries.

Calcite, fluorite and pyrite are primary vein gangue and sulphide, unaltered. Chalcocite belongs to the supergene enrichment zone below the water table, which is reducing, and realgar is a sulphide. Goethite is an oxidation product, but orpiment is an arsenic sulphide and boehmite is an aluminium hydroxide of bauxites, not of base metal veins.

Answer: A

The Himalayan chromite deposits are associated with ophiolite complexes.

Ophiolites are slices of oceanic lithosphere thrust onto continental crust during plate collision. Their mantle section contains podiform chromite bodies in dunite and harzburgite. In the Himalaya such ophiolites lie along the Indus-Tsangpo suture (for example in Ladakh) and in the Nagaland-Manipur belt, and these are the settings of the chromite.

Stratiform complexes such as the Bushveld host layered chromitite seams in stable cratons, Duke Island-type complexes are zoned ultramafic intrusions of Alaska, and intrusive granites are not hosts for chromite at all.

Answer: C

Bailadila is in Chhattisgarh.

The Bailadila range, in Dantewada district of the Bastar region in southern Chhattisgarh, holds high-grade haematite iron ore in banded iron formation. It is mined by NMDC, and its ore has been exported through Visakhapatnam.

Jharkhand (with Odisha) has the Singhbhum-Noamundi iron ore belt, Maharashtra has smaller deposits in Gadchiroli and Chandrapur, and Bihar has no comparable iron ore field. Before 2000 Bailadila was in Madhya Pradesh, which is not among the options.

Answer: C

An iron ore deposit occurs at Kudremukh.

Kudremukh, in the Western Ghats of Chikmagalur district, Karnataka, has large deposits of magnetite-bearing banded iron formation, mined until 2005 by Kudremukh Iron Ore Company Ltd and exported through Mangalore.

Zawar and Dariba, in Rajasthan, are lead-zinc deposits worked by Hindustan Zinc. Rudrasagar, in Assam, is an oil field, not an iron ore deposit.

Answer: A

The correct pair is Uranium - Jaduguda.

Jaduguda, in the Singhbhum shear zone of Jharkhand, has India's first uranium mine, worked by the Uranium Corporation of India since 1967.

The other pairs are mismatched. Khetri in Rajasthan is known for copper, not lead. Panna in Madhya Pradesh is famous for diamonds, not gold. Malanjkhand in Madhya Pradesh is a large copper deposit, not iron.