Rock MCQ Quiz - Objective Question with Answer for Rock - Download Free PDF

The correct answer is Sandstone.

• Sandstone is NOT a metamorphic rock.

Key Points

• Metamorphic rocks are rocks that have become changed by intense heat or pressure while forming.
  • In the very hot and pressured conditions deep inside the Earth's crust, both sedimentary and igneous rocks can be changed into metamorphic rock.
  • ​Metamorphic rock can be formed locally when rock is heated by the intrusion of hot molten rock called magma from the Earth's interior.
    • Some examples of metamorphic rocks are gneiss, slate, marble, schist, and quartzite.
  • Marble, Slate, and quartz are formed after metamorphism. They changed in their original form due to extreme temperatures and pressure.
  • The three types of metamorphism are Contact, Regional, and Dynamic metamorphism.
  • Contact Metamorphism occurs when magma comes in contact with an already existing body of rock.

Additional Information

• Sandstone :
  • Sandstone is a sedimentary rock composed of sand-size grains of mineral, rock, or organic material.
    • It also contains a cementing material that binds the sand grains together and may contain a matrix of silt- or clay-size particles that occupy the spaces between the sand grains.
  • Sandstone is a sedimentary rock composed mostly of quartz sand, but it can also contain significant amounts of feldspar, and sometimes silt and clay.
  • Sandstone that contains more than 90% quartz is called quartzose sandstone.

The correct answer is Tuff.

Key Points

• Tuff is a type of rock that forms from volcanic ash, which is ejected during a volcanic eruption and later compacted and cemented.
• When volcanic ash is carried by running water and deposited as a sedimentary layer, it solidifies into tuff over time.
• Tuff is categorized as a pyroclastic rock, which means it is formed from volcanic materials ejected during explosive eruptions.
• It is commonly composed of fragments of volcanic glass, minerals, and rock particles, often cemented together by fine-grained ash.
• Tuff is widely used in construction due to its light weight and ease of carving, and it has also been used historically for sculptures and buildings.

Additional Information

• Volcanic Ash: Tiny fragments of volcanic glass and mineral particles created during explosive volcanic eruptions. It can be transported by wind or water over long distances.
• Pyroclastic Deposits: These include any material ejected from a volcano during an eruption, such as ash, lapilli, and volcanic bombs, which may accumulate to form rocks like tuff.
• Basalt: A dense, dark-colored igneous rock formed from the rapid cooling of lava at the Earth's surface. It is unrelated to tuff, as it forms directly from lava rather than volcanic ash.
• Lapilli: Small, pea- to walnut-sized fragments of volcanic material that are ejected during an eruption. Unlike tuff, lapilli are not cemented into a solid rock.
• Slate: A metamorphic rock formed from shale under high pressure and temperature. It is unrelated to volcanic processes and should not be confused with tuff.

The correct answer is Igneous.

Key Points

• Igneous rocks are formed through the cooling and solidification of magma or lava.
• Granite is a coarse-grained igneous rock composed mainly of quartz, feldspar, and mica.
• Gabbro is a dense, coarse-grained igneous rock containing mainly plagioclase feldspar and pyroxene.
• Basalt is a fine-grained igneous rock that forms from the rapid cooling of lava at the Earth's surface.
• These rocks are fundamental components of the Earth's crust and are often used in construction due to their durability.

Additional Information

• Igneous Rock Classification
  • Igneous rocks are classified into two main categories: intrusive (plutonic) and extrusive (volcanic).
  • Intrusive igneous rocks, like granite and gabbro, form below the Earth's surface.
  • Extrusive igneous rocks, like basalt, form at the Earth's surface.
  • The texture of igneous rocks depends on the rate of cooling; slow cooling results in larger crystals, while rapid cooling results in smaller crystals.
• Formation Process
  • Magma that cools slowly beneath the Earth's surface forms coarse-grained rocks like granite and gabbro.
  • Lava that cools rapidly on the Earth's surface forms fine-grained rocks like basalt.
  • Igneous rocks can also contain minerals such as olivine, amphibole, and biotite.
• Geological Importance
  • Igneous rocks form the majority of the Earth's crust.
  • They play a crucial role in the rock cycle, transforming into sedimentary and metamorphic rocks over geological time.
  • Igneous rocks are key to understanding the Earth's internal processes and history.
• Uses of Igneous Rocks
  • Granite is widely used in construction, particularly for countertops, flooring, and monuments.
  • Basalt is used in road construction, as an aggregate in concrete, and as a building stone.
  • Gabbro is used as a dimension stone and as a source of crushed stone for construction projects.

The correct answer is Igneous rocks.

Key Points

• Igneous rocks are formed by the solidification and crystallization of molten magma or lava.
• These rocks can form beneath the Earth's surface (intrusive) or on the surface as a result of volcanic activity (extrusive).
• They are primarily composed of silicate minerals, including quartz, feldspar, and mica.
• Igneous rocks are classified based on their texture and composition, with common types being granite (intrusive) and basalt (extrusive).

Additional Information

• Types of Igneous Rocks:
  • Intrusive Igneous Rocks: These rocks form from magma that cools slowly beneath the Earth's surface, resulting in coarse-grained textures. Example: Granite.
  • Extrusive Igneous Rocks: These rocks form from lava that cools quickly on the Earth's surface, resulting in fine-grained textures. Example: Basalt.
• Formation Process: The formation of igneous rocks involves the cooling and solidification of molten material, which can originate from deep within the Earth's mantle or crust.
• Mineral Composition: Common minerals found in igneous rocks include quartz, feldspar, mica, and olivine. The specific mineral composition determines the rock's properties and classification.
• Uses of Igneous Rocks: Due to their hardness and durability, igneous rocks are widely used in construction (e.g., granite for countertops and building stones) and in the production of aggregates for concrete.

The correct answer is Igneous rock.

Key Points

• Gabbro is an example of an intrusive igneous rock.
• It is formed from the slow cooling of magma beneath the Earth's surface.
• Gabbro is coarse-grained and primarily composed of minerals such as pyroxene, plagioclase feldspar, and olivine.
• This type of rock is commonly found in the oceanic crust.
• Gabbro is often used in the construction industry due to its durability and strength.

Additional Information

• Igneous Rocks
  • Formed through the cooling and solidification of magma or lava.
  • Classified into two main types: intrusive (plutonic) and extrusive (volcanic).
  • Common examples include basalt (extrusive) and granite (intrusive).
• Sedimentary Rocks
  • Formed from the accumulation of sediments.
  • Often contain fossils and are typically found in layers.
  • Examples include sandstone, shale, and limestone.
• Metamorphic Rocks
  • Formed from the transformation of existing rock types due to heat, pressure, and chemical processes.
  • Examples include marble (from limestone) and schist (from shale).
  • Metamorphic rocks can exhibit foliation or banding.
• Organically Formed Sedimentary Rocks
  • Formed from the accumulation of plant or animal debris.
  • Examples include coal (from plant material) and limestone (from shell fragments).
  • These rocks provide valuable information about Earth's past environments.

The correct answer is Sandstone.

• Sandstone is NOT a metamorphic rock.

Key Points

• Metamorphic rocks are rocks that have become changed by intense heat or pressure while forming.
  • In the very hot and pressured conditions deep inside the Earth's crust, both sedimentary and igneous rocks can be changed into metamorphic rock.
  • ​Metamorphic rock can be formed locally when rock is heated by the intrusion of hot molten rock called magma from the Earth's interior.
    • Some examples of metamorphic rocks are gneiss, slate, marble, schist, and quartzite.
  • Marble, Slate, and quartz are formed after metamorphism. They changed in their original form due to extreme temperatures and pressure.
  • The three types of metamorphism are Contact, Regional, and Dynamic metamorphism.
  • Contact Metamorphism occurs when magma comes in contact with an already existing body of rock.

Additional Information

• Sandstone :
  • Sandstone is a sedimentary rock composed of sand-size grains of mineral, rock, or organic material.
    • It also contains a cementing material that binds the sand grains together and may contain a matrix of silt- or clay-size particles that occupy the spaces between the sand grains.
  • Sandstone is a sedimentary rock composed mostly of quartz sand, but it can also contain significant amounts of feldspar, and sometimes silt and clay.
  • Sandstone that contains more than 90% quartz is called quartzose sandstone.

The correct answer is sedimentary rock.

Important Points

• Sedimentary rocks are formed by deposition, sedimentation, and lithification of sediments over a long period of time.
• Sedimentary rocks may also contain fossils of plants, animals that once lived on them.
• The word ‘sedimentary’ is derived from the Latin word "sedimentum".
• Shale, limestone, and conglomerate are some other examples of sedimentary rocks.

Key Points

• Sandstone is an example of sedimentary rock.
• Sandstone is made from grains of sand.

Additional Information 

• A rock is an aggregate of one or more minerals.
• Igneous rock is formed due to the cooling, solidification, and crystallization of hot and molten magma.
  • Granite, Basalt, Gabbro are examples of Igneous rocks.
• Metamorphic rocks are made up of sedimentary rock and igneous rock which have been subjected to high pressure and temperature.
  • Clay changes into slate and limestone into marble are the examples of metamorphic rocks.
• Marble and quartzite are examples of non-foliated metamorphic rocks.

The correct answer is i - b, ii - a, iii - c

Key Points

Lithification:

• It refers to the process by which loose and under-consolidated sediment particles transform into hard and solid rocks.
• This process includes a number of geological processes, such as consolidation, deep bury, cementation, recrystallization, and dehydration.

Igneous Rocks:

• As igneous rocks form out of magma and lava from the interior of the earth, they are known as primary rocks.
• The igneous rocks (Ignis – in Latin means ‘Fire’) are formed when magma cools and solidifies.
• When magma in its upward movement cools and turns into a solid form it is called igneous rock.
• The process of cooling and solidification can happen in the earth’s crust or on the surface of the earth.
• Igneous rocks are classified based on texture which depends upon the size and arrangement of grains or other physical conditions of the materials.
• Granite, gabbro, pegmatite, basalt, volcanic breccia, and tuff are some examples of igneous rocks.

Sedimentary Rocks

• The word ‘sedimentary’ is derived from the Latin word sediment, which means settling.
• Rocks (igneous, sedimentary, and metamorphic) of the earth’s surface are exposed to denudational agents and are broken up into various sizes of fragments.
• Such fragments are transported by different exogenous agencies and deposited.
• These deposits through compaction turn into rocks.
• In many sedimentary rocks, the layers of deposits retain their characteristics even after lithification.
• Hence, we see a number of layers of varying thickness in sedimentary rocks like sandstone, shale, geyserite, chalk, limestone, coal etc.

Metamorphic Rocks

• Metamorphic means ‘change of form’.
• These rocks form under the action of pressure, volume, and temperature (PVT) change.
• Metamorphism occurs when rocks are forced down to lower levels by tectonic processes or when molten magma rising through the crust comes in contact with the crustal rocks or the underlying rocks are subjected to great amounts of pressure by overlying rocks.
• Metamorphic rocks are formed due to the proximity of sedimentary rocks with molten magma.
• Mechanical disruption and reorganization of the original minerals within rocks due to breaking and crushing without any appreciable chemical changes are called dynamic metamorphism.
• Examples- Marble, Quartzite, Schist, etc.

Additional Information

Foliation:

• In the process of metamorphism in some rocks grains or minerals get arranged in layers or lines.
• Such an arrangement of minerals or grains in metamorphic rocks is called foliation or lineation.

The correct answer is Intrusive igneous rocks.

Key Points

Concept:

• A rock is any naturally occurring solid mass or aggregate of one or more minerals or mineraloid matter.
• The earth's crust is composed of rocks.
• It is categorized by the minerals included its chemical composition and the way in which it is formed.
• The rock cycle is a basic concept of transitions through geologic time among the three main rock types: sedimentary, metamorphic, and igneous.
• Each rock type is altered when it is forced out of its equilibrium conditions.

Additional Information

The correct answer is Coal.

Key Points

• Gondwana rocks contain nearly 98% of India’s coal reserves.
• The carbon content is very low.
• The Gondwana rock system is also called the Carboniferous rock system.
• They are deposits ordered down in synclinal troughs on ancient tableland surfaces.
• Gondwana System or Carboniferous period System or Dravidian System is the major coal deposit of India. 

• The Gondwana rock system is named after the Gond people, found in Madhya Pradesh, Odisha, etc.
• The deposits were laid down in synclinal troughs on the ancient plateau surface.
• The rock system was formed 250 million years ago.
• Iron ore, copper, uranium, etc are also found here. 
• Rajasthan was the leading producing state accounting for (21%) of the total production of limestone, followed by Madhya Pradesh & Andhra Pradesh (11% each).
• Asia's only active diamond mine is situated in Majhagaon about 55km away from Khajuraho in Madhya Pradesh.
• It is located in the interior of the Panna district.
• The mine is spread over an area of 80km belt, starting from the Paharikhera North-East to Majhgawan South-West with a breadth of around 30 km.
• The major copper mines are the Khetri copper belt in Rajasthan, Singhbhum copper belt in Jharkhand, and Malanjkhand copper belt in Madhya Pradesh which are mined by HCL.
• Singhbhum belt is mined by M/s Indian Copper Complex.

The correct answer is Granite.

Key Points

• Igneous rocks are the most basic type of rocks. They are formed when magma (molten rock, typically derived from the earth's mantle) solidifies.
• This can happen beneath or above the surface, resulting in 2 subtypes:
  • Plutonic rocks
  • Volcanic rocks
• Plutonic rocks: 
  • When magma never reaches the surface and cools to form intrusions (dykes, sills, etc) the resulting rocks are called plutonic.
  • Granite is an example of Plutonic rock.
• Volcanic rocks: 
  • When magma does reach the surface during a volcanic eruption, the rocks that form there are called lavas or volcanic rocks.
• Sedimentary rocks: 
  • Rocks that are formed by the consolidation of sediments of Pre-existing rocks under the mechanical, chemical, or organic activities of the wind, running water, etc are sedimentary rocks.
• Metamorphic rocks: 
  • Rocks that are formed under the influence of heat, pressure or both from pre-existing rocks are called Metamorphic rocks.

There are three types of rocks which include igneous, sedimentary and metamorphic rocks.

Sedimentary Rocks ⇒

• Rocks formed by accumulation, compaction, and consolidation of sediments are sedimentary rocks. It is also known as secondary rocks.
• Examples: Breccia, Limestone, Sandstone, Shale

Metamorphic Rocks ⇒

• Rocks formed due to metamorphism (process responsible for all the changes that take place in an original rock under the influence of changes in the surrounding, conditions of temperature and pressure) are known as metamorphic rocks.
• Examples: Quartzite, Marble, Slate, Phyllite, Schist, Gneiss

Igneous Rock ⇒

• Rocks formed due to cooling or solidification of magma or lava is known as igneous rocks.
• There are two types of igneous rocks:

Intrusive Igneous Rocks 

• These rocks are formed due to cooling/solidification of magma within the crust of a planet. It is also known as Plutonic Rock.
• Examples: Dike, Sill, Granite, Laccolith, etc.

Extrusive Igneous Rocks 

• These rocks are formed due to cooling/solidification of magma at the crust’s surface. It cools faster than the intrusive one.
• Examples: Basalts, Traps, Black Smokers, etc.

Additional Information

Actually, there exists a rock cycle that again melts metamorphic rocks into magma through heat and pressure and forms igneous rocks.

Refer to the image for further information:-

The correct answer is Metamorphic.

Key Points

• Metamorphic Rocks
  • These rocks form under the action of volume, pressure, and temperature (PVT) changes.
  • Metamorphism happens when rocks are forced down to lower levels by tectonic processes or when molten magma rising through the crust comes in contact with the crustal rocks or the underlying rocks are exposed to great amounts of pressure by overlying rocks.
  • The materials of rocks chemically modify and recrystallize due to thermal metamorphism.
  • There are two types of thermal metamorphism: Contact metamorphism and Regional metamorphism.
  • Contact metamorphism: The rocks come in contact with hot intruding magma and lava and the rock materials recrystallize under high temperatures.
  • Regional metamorphism: The rocks experience recrystallization due to deformation caused by tectonic shearing together with high temperature or pressure or both.
  • Quartzite is a metamorphic rock. Hence, Option 4 is correct.
    • The original form of Quartzite is pure quartz sandstone. 
    • It is formed when quartz-rich sandstone is exposed to high temperatures and pressures.
    • Quartzite is mainly formed through two types of metamorphism namely Contact and Barrovian.

Additional Information

A rock is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. There are three kinds of rock: igneous, sedimentary, and metamorphic. Igneous rocks.

Metamorphic rock:

• The word metamorphic means ‘change of form’.
• These rocks form under the action of pressure, volume, and temperature (PVT) changes. 
• Metamorphism is a process by which already consolidated rocks undergo recrystallization and reorganization of materials within original rocks
• Metamorphic rocks can be classified into foliated or non-foliated rocks.
• Gneissoid, syenite, slate, schist, marble, quartzite, etc. are some examples of metamorphic rocks. 

Hence, Limestone is not a metamorphic rock.

The correct answer is Option 1. 

Key Points

• Sedimentary rocks are formed by the accumulation and consolidation of sediment over time.
• They often contain fossils of plants, animals, and other microorganisms that lived in the past.
• Fossils are commonly found in sedimentary rocks because these rocks preserve the remains or traces of ancient life forms.
• Extrusive igneous rocks form from lava cooling on the Earth's surface, and while they can sometimes contain fossils preserved from nearby sedimentary rocks, it is less common.
• Metamorphic rocks are formed through the alteration of existing rocks under high heat and pressure, and they typically do not contain fossils. Intrusive igneous rocks form from magma cooling beneath the Earth's surface and generally do not contain fossils either.

Additional Information

• Extrusive igneous rocks are formed from lava that cools and solidifies on the Earth's surface.
  • This lava is typically erupted from volcanoes or fissures and then rapidly cools as it comes into contact with the cooler air or water.
  • Examples of extrusive igneous rocks include basalt, andesite, and rhyolite.
  • Unlike sedimentary rocks, extrusive igneous rocks are not known for preserving fossils of plants, animals, or microorganisms.
  • Fossils are primarily found in sedimentary rocks because the processes of sedimentation and burial help to protect and preserve the remains or traces of ancient life forms.
  • However, it's worth noting that in some cases, extrusive igneous rocks can preserve fossils that were captured or trapped within them during an eruption if they were near or in contact with sedimentary rocks containing fossils.
  • This is relatively rare, and the vast majority of fossils are found in sedimentary rocks.
• Metamorphic rocks are formed through the process of metamorphism, which involves the transformation of pre-existing rocks under high temperature and pressure conditions.
  • Metamorphism occurs deep within the Earth's crust and can be caused by tectonic forces, intense heat from magma intrusion, or burial under thick layers of sediment.
  • Metamorphic rocks undergo changes in mineral composition, texture, and structure, but they do not typically contain fossils.
  • The intense heat and pressure associated with metamorphism often destroy any organic remains or fossils that may have been present in the original rock.
  • The recrystallization and reordering of minerals during metamorphism erase the original structures, including any fossil evidence.
• ​Intrusive igneous rocks, also known as plutonic rocks, are formed from the cooling and solidification of magma deep beneath the Earth's surface.
• Unlike extrusive igneous rocks, which form from lava that erupts onto the surface, intrusive rocks cool and solidify slowly within the crust.