Very Short Questions: Minerals and Energy Resources

Q1: What are rocks?
Ans: Rocks are the combinations of homogenous substances called minerals. They form the solid outer part of the Earth and are made up of one or more minerals joined together in different proportions.

Q2: What is the role of a geologist in studying about a mineral?
Ans: A geologist is interested in the formation of minerals, their age and physical and chemical composition. They also study how minerals are distributed, their economic importance and the methods used to locate and extract them.

Q3: What is an 'ore'?
Ans: The term 'ore' is used to describe an accumulation of any mineral mixed with other elements. The mineral content of the ore must be in sufficient concentration to make its extraction commercially viable. In other words, only those mineral deposits that can be mined at a profit are called ores.

Q4: What are 'veins' and 'lodes'?
Ans: In igneous and metamorphic rocks, minerals may occur in the cracks, crevices, faults or joints. The smaller occurrences are called veins and the larger are called lodes. Veins are usually narrow sheets of mineral filling cracks, while lodes are wider and more extensive bodies of mineralisation.

Q5: How are minerals formed in veins and lodes?
Ans: In most cases, they are formed when minerals in liquid molten and gaseous forms are forced upwards, through cavities towards the earth's surface. They cool and solidify as they rise. This process concentrates minerals in cracks and openings, creating veins and lodes that can be mined.

Q6: Name the minerals obtained from veins and lodes.
Ans: Major metallic minerals like tin, copper, zinc and lead, etc. are obtained from veins and lodes. These are important metallic ores often mined by underground methods where veins and lodes occur.

Q7: In what form do minerals occur in sedimentary rocks?
Ans: In sedimentary rocks, minerals occur in the form of 'beds' and 'layers'. These beds are generally horizontal and may extend over large areas.

Q8: How are minerals formed in sedimentary rocks?
​Ans: They are formed as a result of deposition, accumulation and concentration in horizontal states. Particles carried by water or wind settle down and are compacted over time to form layered mineral deposits.

Q9: Name the minerals formed in beds and layers.
Ans: Sedimentary minerals include iron ore, coal, gypsum, potash salt and sodium salt. These minerals form as sediments build up and are important for industry and agriculture.

Q10: What are 'placer deposits'?
Ans: When minerals occur as alluvial deposits in sands of valley floors and the base of hills, then deposits are called 'placer deposits'. They form where running water has separated and concentrated heavy mineral grains, making them easier to recover.

Q11: Name minerals formed as 'placer deposits'.
Ans: Gold, silver, tin and platinum are the most important ones among minerals formed as 'placer deposits'. These are often found in stream beds, river terraces and coastal alluvium.

Q12: Which minerals are derived from oceanic waters?
Ans: Common salt, magnesium and bromine are largely derived from ocean waters. These are usually obtained by evaporation of seawater or by chemical extraction from brines.

Q13: Which factors affect the economic viability of a reserve?
Ans: The concentration of minerals in the ore, the ease of extraction and closeness to the market play an important role in affecting the economic viability of a reserve. Other factors such as availability of infrastructure, labour and demand for the mineral also influence whether a reserve is worth mining.

Q14: What are ferrous minerals?
Ans: Minerals which contain iron-content in it are called ferrous minerals. These minerals are used mainly to produce iron and steel and include ores such as haematite and magnetite.

Q15: What is Magnetite?
Ans: Magnetite is the finest iron ore with a very high content of iron upto 70 per cent. It has excellent magnetic qualities, which are especially valuable in electrical and industrial applications.

Q16: What is Haematite?
Ans: Haematite ore is the most important industrial iron ore in terms of the quantity used, but has a slightly lower iron content than magnetite, i.e., 50-60 per cent. It is widely used in steel-making because of its abundance and ease of mining.

Q17: Name the two types of iron-ore found in India.
Ans: Magnetite and Haematite. Both are important sources of iron for India's steel industry.

Q18: In which places of Odisha-Jharkhand belt is iron ore found?
Ans: High grade Hematite iron ore is found in Badampahar mines in Mayurbhanj and Kendujhar district and in Singhbhum District of Jharkhand, iron-ore is mined in Gua and Noamundi. These areas form a major iron-ore belt that supplies both domestic and export demand.

Q19: Where are Bailadila hills located and why are they called so?
Ans: Bailadila hills are located in the Bastar District of Chattisgarh. These Bailadila hills look like the 'hump of an ox', hence they are called so.

Q20: Name the countries to which iron-ore is exported from Bailadila hills.
Ans: Iron-ore from these mines is exported to Japan and South Korea via Vishakhapatnam port. These exports supply high-grade ore to steel industries in those countries.