Mining Geology — Part 1 MCQs with Explanations

Intrusive rocks are formed from magma that cools and solidifies beneath the Earth's surface. These rocks can take various forms based on their shape, size, and relationship to the surrounding rock. The different types of intrusive rocks include: Batholith , which are large, deep-seated intrusive bodies. Laccolith , which are dome-shaped intrusions that cause the overlying rock to bulge upwards. Dyke , which are vertical or steeply inclined sheets of rock that cut across pre-existing layers. Sill , which are horizontal or gently inclined sheets of rock that run parallel to the layering of the surrounding rocks. Therefore, the correct answer is all of these .

India’s share of global proved coal reserves is commonly rounded to about 8% in standard mining-geology references and competitive exams. While modern statistical reviews may report figures in the ~9–10% range depending on the year and methodology, exam keys traditionally accept 8% as the representative value. This also aligns with India’s position among the top coal-reserve holders globally (after the U.S., Russia, Australia, and China), supporting the choice of Option C .

The process of gradual wear and tear of exposed country rocks due to mechanical action is known as abrasion . It occurs when rock fragments, sand, or other particles are carried by agents like wind, water, or ice and strike against the surface of exposed rocks, causing them to erode. Option A: Attrition refers to the wear and rounding of rock particles due to collision with one another, not the wearing of fixed country rocks. Option C: Deflation refers to the removal of loose particles by wind, not the wearing of hard rock surfaces. Option D: Suspension refers to the transport of fine particles in air or water, not the erosion of country rocks. Therefore, the process of wear and tear of exposed country rocks is called abrasion .

Denudation is the geological process that refers to the wearing away and removal of exposed country rocks from the Earth’s surface by natural agents such as running water, glaciers, wind, and waves. It includes processes like weathering, erosion, transportation, and mass wasting , which together lower and reshape the land surface. Option A: Attrition refers to the mutual wear and rounding of rock particles when they collide with one another, not the general wearing away of exposed rocks. Option B: Mantle refers to a geological layer inside the Earth, not a surface process. Option D: Deflation refers specifically to the removal of loose fine particles by wind, not the overall wear and tear of rocks. Thus, the process of wear and tear of exposed country rocks is best defined as Denudation .

Mural joints are vertical joints that commonly develop in massive igneous rocks, especially in granite bodies. They are formed due to contraction and release of stresses during the cooling and solidification of the granite mass. These joints are called mural joints because they appear like the walls of a structure, often intersecting at right angles. Option A: Basalt usually develops columnar joints, not mural joints. Option C: Sandstone may show bedding and fracture joints but not mural joints. Option D: None is incorrect because mural joints specifically occur in granite . Therefore, mural joints are typically developed in granite .

The Precambrian period is the earliest and longest span of geological time, covering nearly 90% of Earth’s history . It began with the formation of the Earth about 4600 million years ago and lasted until the start of the Cambrian period, around 541 million years ago . The Precambrian is therefore roughly 4000 million years old , making it the correct answer. Option A: 110 million years is too small and belongs to much later geological eras. Option B: 215 million years falls within the Mesozoic era (Triassic period), not Precambrian. Option C: 1500 million years represents only a part of the Precambrian, not its full duration. Thus, the age in million years of the Precambrian period is approximately 4000 .

An anticline fold is a type of geological fold that has the following characteristics: Convex upward: The fold arches upward, forming a convex shape when viewed in cross-section. Hence, Option A is correct. Older rocks in centre: Due to the upward arching, the oldest rock layers are exposed in the central part of the anticline, with progressively younger rocks towards the limbs. Hence, Option B is correct. Two limbs dip away from each other: In an anticline, the limbs slope away from the crest of the fold. Hence, Option C is correct. Since all three conditions are true for an anticline fold, the correct answer is Option D: All of these .

Silica is the correct answer to “On the basis of which content the igneous rocks are classified as acid rocks and basic rocks”. This question is standard in competitive examination syllabi for Mining Geology.

A and B both is the correct answer to “Origin of Solar System divided in two groups, which are”. This question is standard in competitive examination syllabi for Mining Geology.

Deflation is the correct answer to “The process of removal of loose soil or rock particles during storm, along the course of the blowing wind is defined as”. This question is standard in competitive examination syllabi for Mining Geology.

Quartzite is the correct answer to “If sandstone is the original rock then what is its metamorphic rock”. This question is standard in competitive examination syllabi for Mining Geology.

Throw of fault is the correct answer to “In respect of fault, the vertical displacement of the fractured bed is called”. This question is standard in competitive examination syllabi for Mining Geology.

Swamps is the correct answer to “The low-lying lands where the water table has reached the land surface and which commonly occur along food plains of rivers and in low lying sea-shores. Such areas are known as”. This question is standard in competitive examination syllabi for Mining Geology.

Dyke is the correct answer to “It is more or less parallel sided vertical wall of igneous rock formed due to upward intrusion of molten magma through fissures or cracks and is a common occurrence in coalfields. Guess it as”. This question is standard in competitive examination syllabi for Mining Geology.

Outcrop is the correct answer to “A part of any stream or rock that is exposed at the surface is known as”. This question is standard in competitive examination syllabi for Mining Geology.

Fusain is the correct answer to “Dull, friable appearance that soil the finger and most impure band in coal is known as”. This question is standard in competitive examination syllabi for Mining Geology.

Sinters is the correct answer to “Underground water emerging on the surface in the form of seepages and springs is found to form loose superficial deposits of silica or calcium carbonates. Such deposits are known as”. This question is standard in competitive examination syllabi for Mining Geology.

Dihing series is the correct answer to “The top most horizon of the tertiary succession in Assam is known as”. This question is standard in competitive examination syllabi for Mining Geology.

Heave of fault is the correct answer to “The horizontal component of the apparent displacement of a bed, measured along the direction of dip of the fault is”. This question is standard in competitive examination syllabi for Mining Geology.

Volcano is the correct answer to “It's a mere openings of any shape or size which act as avenues for the magma to rise and spread upon earth's surface in the form of lava.”. This question is standard in competitive examination syllabi for Mining Geology.

Igneous rocks is the correct answer to “Rocks that are formed by the cooling of molten material (called magma) at or relatively near the earth surface is called”. This question is standard in competitive examination syllabi for Mining Geology.

Transverse fault is the correct answer to “Dip fault also called”. This question is standard in competitive examination syllabi for Mining Geology.

Bedding plane is the correct answer to “It is the junction plane of one bed of rock with another”. This question is standard in competitive examination syllabi for Mining Geology.

Loess is the correct answer to “It is a buff coloured deposit made up of angular fragments of unaltered mineral grains and is characteristically unstratified. The thickness of such deposit may vary from few inches to hundreds of feet”. This question is standard in competitive examination syllabi for Mining Geology.

Telangana is the correct answer to “Low temperature carbonisation plants are at”. This question is standard in competitive examination syllabi for Mining Geology.

Jigging is the correct answer to “It is another method of washing which separate good quality coal from its impurities through a simple process of particle stratification”. This question is standard in competitive examination syllabi for Mining Geology.

Petrification is the correct answer to “In palaeontology the conversion of remains of plants and animals into rock is known as”. This question is standard in competitive examination syllabi for Mining Geology.

Tectonic earthquakes is the correct answer to “Seismic shocks that originate due to crustal movements are defined as”. This question is standard in competitive examination syllabi for Mining Geology.

Tenor is the correct answer to “A deposit must contain at least certain percentage of metal in it and the lowest admissible limit of metallic content of an ore is known as”. This question is standard in competitive examination syllabi for Mining Geology.

Deccan trap is the correct answer to “Large lave flows give rise to flat topped mountains and plateaus called as”. This question is standard in competitive examination syllabi for Mining Geology.

Green is the correct answer to “Colour of Olivene is generally”. This question is standard in competitive examination syllabi for Mining Geology.

Moisture is the correct answer to “In order to calculate useful heat value in Kcal per Kg of non-coking coal, besides ash percentage what is the name of other character which is considered”. This question is standard in competitive examination syllabi for Mining Geology.

Economic geology is the correct answer to “The branch of Geology that deals principally with the mode of occurrence, origin, distribution, classification and association of all minerals and rocks of economic importance is called”. This question is standard in competitive examination syllabi for Mining Geology.

Gray is the correct answer to “Colour of Galena”. This question is standard in competitive examination syllabi for Mining Geology.

Physical and chemical character of magma is the correct answer to “The nature of eruption of volcano is principally guided by”. This question is standard in competitive examination syllabi for Mining Geology.

Hardness of rocks is the correct answer to “Protodyakonov strength number is used to denote”. This question is standard in competitive examination syllabi for Mining Geology.

Unconformity is the correct answer to “The plane of contact between the two series of strata is called”. This question is standard in competitive examination syllabi for Mining Geology.

Agglutinating index is the correct answer to “Caking index is also known as”. This question is standard in competitive examination syllabi for Mining Geology.

Strike is the correct answer to “Trend of a rock bed on ground surface”. This question is standard in competitive examination syllabi for Mining Geology.

Palaeontology is the correct answer to “The study of fossils within rock beds and their proper utilization in elucidating the past history of the earth is called”. This question is standard in competitive examination syllabi for Mining Geology.