Minerals and Energy Resources

Question 1

What is a mineral?

Answer 1

Geologists define minerals as a homogenous naturally occurring substance with a definable internal structure.

Question 2

What is the mode of occurrence of minerals?

Answer 2

1. Igenous and metamorphic rocks occur in cracks, crevices, faults, and joints - Molten liquid pushed out of the Earth’s surface through cavities - they cool and solidify - smaller occurrences are veins - bigger ones are lodes - copper, tin, and zinc, lead
2. Sedimentary rocks - beds and layers - deposition, accumulation, concentration in the horizontal strata - iron ore and coal - subject to high heat and pressure
3. Evaporation - gypsum, potash salts and sodium salts - arid areas
4. Decomposition of surface rocks - residual mass of weathered rock - Bauxite
5. Placer deposits - base of hills/ valley floor - non corrosive minerals - gold, tin, silver, platinum
6. Ocean beds - magnesium, bromine, manganese nodules - too widely diffused to be of economic use

Question 3

India is fortunate to have fairly rich and varied mineral resources, however, they are unevenly distributed.

Answer 3

1. Peninsular plateau - coal, metallic minerals, non-metallic minerals, mics
2. Sedimentary rocks - eastern and western flanks of the peninsula
3. Gujarat and Assam have petroleum deposits
4. Rajasthan - reserved of non ferrous minerals
5. Alluvial plains are mostly devoid of minerals