All questions of Geomorphology (Part 1) for BPSC (Bihar) Exam

Explanation:

Volcanoes and earthquakes are natural phenomena that occur due to the movement of tectonic plates. These plates make up the Earth's crust and are constantly shifting and colliding with each other. The majority of volcanoes and earthquakes in the world are located at plate margins.

Plate Margins:

Plate margins are the boundaries where two tectonic plates meet. There are three main types of plate boundaries:

1. Divergent Boundaries: This is where two plates move away from each other. This movement creates a gap between the two plates which magma rises up to fill, creating new crust. This is where most of the world's volcanoes are located.

2. Convergent Boundaries: This is where two plates move towards each other. This movement can cause one plate to be forced under the other, creating a subduction zone. This can cause earthquakes and volcanic eruptions.

3. Transform Boundaries: This is where two plates slide past each other horizontally. This can cause earthquakes but rarely causes volcanic eruptions.

Conclusion:

In conclusion, the majority of volcanoes and earthquakes in the world are located at plate margins. The movement of tectonic plates at these boundaries causes geological activity such as volcanic eruptions and earthquakes. Understanding plate tectonics and plate boundaries is important for predicting and mitigating the risks associated with these natural phenomena.

The question is asking about the incorrect statement but here both statement are correct so the option (D) is correct.

Explanation:
Not sedimentary rocks:
- Limestone: Limestone is a sedimentary rock formed from the remains of marine organisms such as coral and shells. It is composed mostly of calcium carbonate.
- Marble: Marble is a metamorphic rock formed from limestone that has undergone heat and pressure. It is composed of recrystallized carbonate minerals.
Therefore, limestone and marble are not sedimentary rocks, unlike sandstone and slate.

Oldest Rocks in the World

The oldest rocks in the world are found in Western Australia.

Evidence

- The rocks in Western Australia are known as the Jack Hills group and have been dated to be 4.4 billion years old.
- These rocks were formed during the Hadean Eon, which lasted from the formation of the Earth around 4.6 billion years ago to the beginning of the Archean Eon around 4 billion years ago.
- The rocks contain tiny zircon crystals which have been used to determine their age.
- The zircon crystals have been found to be up to 4.4 billion years old, making them the oldest known rocks in the world.

Importance

- The discovery of these rocks in Western Australia has important implications for our understanding of the early Earth.
- It suggests that the planet was able to cool and solidify much faster than previously thought.
- It also suggests that conditions on the early Earth were more hospitable for life than previously thought, as life is believed to have emerged around 3.5 billion years ago.

Conclusion

In conclusion, the oldest rocks in the world are found in Western Australia and are known as the Jack Hills group. These rocks have been dated to be 4.4 billion years old and contain tiny zircon crystals which have been used to determine their age. The discovery of these rocks has important implications for our understanding of the early Earth and the emergence of life.

Explanation:

Pole fleeing force is a term used to describe the outward-directed force associated with the spinning of the Earth. This force is also known as centrifugal force. It is the force that causes objects at or near the Earth's equator to experience a slight outward push. This force is due to the rotation of the Earth on its axis.

The centrifugal force is a result of the Earth's rotation, which causes the equator to bulge outwards slightly and the poles to flatten slightly. It is important to note that the pole fleeing force is not responsible for the bulging at the Earth's poles, which is primarily caused by the Earth's rotation and the gravitational pull of the Sun and Moon.

The pole fleeing force is an important factor to consider when studying the Earth's rotation. It influences the Earth's shape, the distribution of mass within the Earth, and the motion of the Earth's oceans and atmosphere.

Conclusion:

In summary, the pole fleeing force is the outward-directed force associated with the spinning of the Earth. It is not responsible for the bulging at the Earth's poles but is an important factor to consider when studying the Earth's rotation.

Features of Limestone Caves

Limestone caves are formed when water flows through porous rocks and dissolves the limestone, creating caverns and passageways. These caves often have unique and beautiful features that are a result of this geological process. The three main features that adorn the limestone caves are:

1. Stalactites: These are mineral deposits that hang from the ceiling of the cave and are formed by the dripping of mineral-rich water. Over time, the water evaporates, leaving behind a deposit of minerals that grows downwards. Stalactites can take on many shapes and sizes and are often found in clusters.

2. Stalagmites: These are mineral deposits that rise from the floor of the cave and are formed by the same process as stalactites. As water drips onto the cave floor, it leaves behind mineral deposits that grow upwards. Stalagmites can take on many shapes and sizes and are often found in clusters.

3. Pillars: Pillars are formed when stalactites and stalagmites merge together over time. As a stalactite grows downwards and a stalagmite grows upwards, they eventually meet and merge, forming a column or pillar. These pillars can be massive and create stunning natural formations in the cave.

Therefore, the correct answer is option 'D' - All of them.

Introduction:
The given statements are related to the impact of glacial activity on lakes and agricultural development. Let us analyze each statement and its correctness.

Statement 1: Morainic deposits may dam, or glaciers may hollow out, lakes which greatly inconvenience large-scale farming or land development.
- Glaciers are massive bodies of ice that move slowly under their own weight. As they move, glaciers can create various landforms, including lakes.
- Morainic deposits are accumulations of rocks, soil, and other debris carried and deposited by glaciers.
- Glaciers can hollow out lakes by eroding the land and creating depressions or basins.
- Alternatively, when glaciers retreat or melt, they can leave behind morainic deposits that dam natural drainage systems, resulting in the formation of lakes.
- These lakes can greatly inconvenience large-scale farming or land development as they occupy valuable land and restrict agricultural activities.

Statement 2: But when the lakes are eliminated, the old glacial lake beds with their rich alluvium support heavy cropping.
- When the lakes formed by morainic deposits are eliminated, the old glacial lake beds are exposed.
- These lake beds are typically composed of rich alluvium, which is a fertile soil deposit made up of sediment carried and deposited by water.
- The alluvial soil in the old glacial lake beds is highly fertile and suitable for agriculture.
- The presence of alluvium supports heavy cropping, meaning that large-scale agricultural activities can be carried out on these lands.

Correctness of the statements:
- Statement 1 is correct as glaciers can either dam lakes through morainic deposits or hollow out lakes through erosion, which can inconvenience large-scale farming or land development.
- Statement 2 is also correct as the elimination of lakes formed by glaciers exposes the old glacial lake beds, which are rich in alluvium and support heavy cropping.

Conclusion:
Both statements 1 and 2 are correct. The formation of lakes by glacial activity can hinder agricultural development, but the elimination of these lakes exposes fertile alluvial soil that supports heavy cropping.

Sources of earthquakes

• Tectonic earthquakes - sliding of plates along a fault plane.
• Volcanic earthquakes - Collapse of roofs of underground mines.

Weathering of rocks:
- Weathering is the process by which rocks are broken down into smaller pieces or undergo chemical changes due to exposure to various environmental factors such as wind, water, and temperature changes.
- As rocks undergo weathering, the minerals present in them are released and become available for other processes to act upon.
- This weathering process can be physical, such as the freezing and thawing of water in cracks, or chemical, such as the reaction of rock minerals with water or acids.
- The weathering of rocks plays a significant role in the enrichment of minerals in rocks because it breaks down the rock into smaller particles, exposing more surface area for chemical reactions to occur.

Erosional and depositional action of rivers:
- Rivers play a crucial role in the transportation and deposition of sediments.
- As rivers flow, they erode the land, carrying sediments such as rocks, minerals, and soil particles.
- These sediments are transported downstream and eventually deposited when the river's velocity decreases, such as in river bends or at the mouth of the river.
- During this process, minerals that were weathered from rocks in the upstream areas are carried by the river and deposited in new locations.
- The erosional and depositional action of rivers helps in redistributing and concentrating minerals, thereby contributing to the enrichment of minerals in rocks.

Both (a) and (b):
- Both weathering of rocks and the erosional and depositional action of rivers contribute to the enrichment of minerals in rocks.
- Weathering breaks down rocks, releasing minerals and making them available for other processes.
- Rivers then transport these minerals and deposit them in new locations, contributing to the enrichment of minerals in rocks.
- The combined action of weathering and rivers helps in the concentration and redistribution of minerals, ultimately leading to the enrichment of minerals in rocks.

Therefore, the correct answer is option 'C' - Both (a) and (b).

Explanation:
The correct answer is option 'D' - None of the above.

Let's analyze each statement one by one:

Statement 1:
A river drains the water collected from a specific area, which is called its 'catchment area'.

This statement is correct. A river collects water from a specific area, which is known as its catchment area. The catchment area is the area of land where the rainwater or snowmelt flows into the river and its tributaries.

Statement 2:
An area drained by a river and its tributaries is called a drainage basin.

This statement is correct. A drainage basin refers to the area of land that is drained by a river and its tributaries. It includes all the land where the water flows into the river system.

Statement 3:
The boundary line separating one drainage basin from the other is known as the watershed.

This statement is incorrect. The boundary line separating one drainage basin from the other is known as the watershed, not the catchment area. The watershed is the dividing line between two drainage basins, where the water flows in different directions.

Statement 4:
Watersheds are small in area while the basins cover larger areas.

This statement is incorrect. Watersheds are not necessarily small in area compared to basins. The size of a watershed or a drainage basin can vary greatly depending on various factors such as the size of the river and the topography of the land. Some watersheds can be large, covering a vast area, while others can be relatively small.

In conclusion, statement 3 is incorrect while the other statements are correct. Hence, the correct answer is option 'D' - None of the above.

Sedimentary rocks make up about three-quarters of the rocks at the Earth’s surface.

• Sedimentary rocks preserve a record of the environments that existed when they formed. By looking at sedimentary rocks of different ages, scientists can figure out how climate and environments have changed through Earth’s history. Fossils of ancient living things are preserved in sedimentary rocks too.
• Quartz, K-feldspar and muscovite are some of the important minerals found there.

Sedimentary rocks can be directly formed from which of the following:

1. Magma
2. Igneous rocks
3. Metamorphic rocks

The correct answer is option 'B' which is 2 and 3 only.

Explanation:
Sedimentary rocks are formed from the accumulation of sediments or organic matter that have been deposited in layers over time. These sediments can come from a variety of sources such as weathering and erosion of other rocks, as well as the remains of plants and animals.

Sedimentary rocks can be directly formed from two types of rocks:

1. Igneous rocks: These rocks are formed from the cooling and solidification of magma or lava. When these rocks are weathered and eroded, they can break down into sediments which can then be deposited and compacted to form sedimentary rocks.

2. Metamorphic rocks: These rocks are formed from the alteration of pre-existing rocks due to heat and pressure. When these rocks are weathered and eroded, they can break down into sediments which can then be deposited and compacted to form sedimentary rocks.

However, sedimentary rocks cannot be directly formed from magma as it cools and solidifies to form igneous rocks, nor from metamorphic rocks as they are already altered from pre-existing rocks.

Therefore, the correct answer is option 'B' which is 2 and 3 only.

The Mid-Ocean Ridge system forms the most extensive chain of mountains on Earth, with more than 90% of the mountain range lying in the deep ocean - with a total length of about 60,000 km. Mid-ocean ridges are geologically important because they occur along divergent plate boundaries, where the new ocean floor is created as the Earth’s tectonic plates spread apart. As the plates separate, some molten rock rises to the seafloor, producing enormous volcanic eruptions of basalt, and building the longest chain of volcanoes in the world. Because most of these eruptions occur deep under the water, they often go unnoticed.

Difference between Extrusive and Intrusive Rocks

Introduction
Extrusive and intrusive rocks are two types of igneous rocks that differ in their formation, texture, and the duration of their formation. Understanding these differences is important in the study of geology and helps in identifying and classifying various rock formations.

Formation
1. Extrusive Rocks: Extrusive rocks are formed from magma, which is molten rock that reaches the Earth's surface through volcanic activity. When magma erupts from a volcano, it cools rapidly and solidifies to form extrusive rocks. Examples of extrusive rocks include basalt, obsidian, and pumice.

2. Intrusive Rocks: Intrusive rocks, on the other hand, are formed from lava, which is magma that has reached the Earth's surface. Instead of erupting, lava flows out of the volcano and cools slowly beneath the surface. This slow cooling allows for the formation of large mineral crystals, resulting in coarse-grained textures. Examples of intrusive rocks include granite, gabbro, and diorite.

Texture
1. Extrusive Rocks: Extrusive rocks have a fine-grained texture due to their rapid cooling. As the magma cools quickly at the surface, there is insufficient time for large mineral crystals to form. Instead, small crystals or even glassy structures are observed in extrusive rocks.

2. Intrusive Rocks: Intrusive rocks have a coarse-grained texture because of their slow cooling process. As the magma cools slowly beneath the surface, there is ample time for large mineral crystals to develop. These crystals are often visible to the naked eye and contribute to the coarse-grained appearance of intrusive rocks.

Duration of Formation
1. Extrusive Rocks: Extrusive rocks are formed relatively quickly, as the magma reaches the surface and cools rapidly. This process typically takes place over a short duration of time, such as days or weeks.

2. Intrusive Rocks: In contrast, the formation of intrusive rocks occurs over a much longer duration of time. The slow cooling of lava beneath the surface can take thousands or even millions of years, allowing for the growth of large mineral crystals.

Conclusion
In summary, extrusive and intrusive rocks differ in their formation, texture, and the duration of their formation. Extrusive rocks are formed from magma, have a fine-grained texture, and are formed relatively quickly. In contrast, intrusive rocks are formed from lava, have a coarse-grained texture, and are formed over a longer duration of time. Understanding these differences is essential in the study of igneous rocks and helps in identifying and classifying various geological formations.

Overview of Metallic and Non-Metallic Minerals
Understanding the distribution of metallic and non-metallic minerals is essential in geology and resource management. Let’s analyze each statement to clarify their correctness.
Statement 1: Metallic Minerals in Igneous and Metamorphic Rocks
- Metallic minerals are typically found in igneous and metamorphic rocks because these rocks are formed under high temperatures and pressures, conditions conducive to the formation of metallic deposits.
- Large plateaus, often formed by volcanic activity or tectonic uplift, are common locations for these types of minerals.
Statement 2: Non-Metallic Minerals in Sedimentary Formations
- Sedimentary rock formations, particularly in plains and young fold mountains, are known to contain non-metallic minerals like limestone, gypsum, and salt.
- The formation processes of these rocks often involve sedimentation, which leads to diverse mineral deposits that are primarily non-metallic.
Statement 3: Organic Formation of Sedimentary Rocks
- Sedimentary rocks can indeed form organically. For instance, limestone can form from the accumulation of shells and coral, while coal is created from the remains of plant material.
- This process illustrates the biological contribution to sedimentary rock formation, confirming that not all sedimentary rocks are purely clastic or chemical in origin.
Conclusion
- All three statements are correct. Therefore, the correct answer is option 'D': All of the above.
- This understanding is crucial for resource exploration and management in various geological settings, particularly in the context of sustainable development and environmental considerations.

Batu Caves, Kuala Lumpur, Mammoth Caves, Kentucky and Carlsbad Cave, New Mexico, in U.S.A. and Postojna Caves, Yugoslavia.

Explanation:

Metamorphic rocks are formed when existing rocks, either igneous or sedimentary, undergo a transformation due to intense heat and pressure. This process causes the minerals in the rocks to recrystallize, resulting in a new rock with different physical and chemical properties.

The correct conversions to metamorphic rocks are:

1. Clay to slate: Clay is a sedimentary rock composed mainly of fine-grained minerals. Under high pressure and temperature, the minerals in the clay recrystallize, forming a dense, fine-grained rock called slate. Slate is characterized by its ability to be easily split into thin, flat sheets.

2. Coal to graphite: Coal is a sedimentary rock formed from the remains of plant material. When subjected to high temperature and pressure, coal undergoes a metamorphic transformation and turns into graphite. Graphite is a crystalline form of carbon with a layered structure and is known for its lubricating properties and use in pencils.

3. Sandstone to quartzite: Sandstone is a sedimentary rock composed of sand-sized grains of mineral, rock, or organic material. Under intense heat and pressure, the sand grains in sandstone recrystallize and fuse together, forming a harder and more compact rock called quartzite. Quartzite is composed mainly of quartz and is known for its durability and resistance to weathering.

4. Shale to schist: Shale is a sedimentary rock composed of fine particles of clay minerals. When subjected to high temperature and pressure, shale undergoes metamorphism and transforms into a metamorphic rock called schist. Schist is characterized by its foliated texture, with minerals aligned in layers or bands.

Therefore, the correct conversions to metamorphic rocks are 1, 2, 3, and 4. Thus, option 'D' - "All of the above" is the correct answer.

The major characteristics of the Archaean rock system can be summarized as follows:

a) Formed before the appearance of life in the geologic sequence:
The Archaean rock system refers to the oldest rock system on Earth, which formed between 4 to 2.5 billion years ago. It predates the appearance of life on Earth, as the first evidence of life dates back to around 3.5 billion years ago. Therefore, the Archaean rock system was formed before the appearance of life in the geologic sequence.

b) Not the first metamorphic sedimentary rock:
While the Archaean rock system is known for its high-grade metamorphic rocks, it is not the first metamorphic sedimentary rock system. Metamorphic rocks are formed from pre-existing rocks under conditions of high temperature and pressure. The Archaean rock system is primarily composed of igneous rocks, which were formed through volcanic activity.

c) Not the host of major coal deposits of India:
The major coal deposits of India are primarily found in the Gondwana rock system, which formed during the Permian and Carboniferous periods, around 300 to 200 million years ago. The Archaean rock system, being much older, does not host the major coal deposits of India.

d) Largely igneous rocks:
The Archaean rock system is predominantly composed of igneous rocks. Igneous rocks are formed through the solidification and crystallization of molten magma or lava. The Archaean rock system is characterized by the presence of various types of igneous rocks, including granite, gneiss, and greenstone belts. These rocks provide valuable insights into the early history of Earth's formation and the processes that shaped its crust.

In conclusion, the major characteristic of the Archaean rock system is that it was formed before the appearance of life in the geologic sequence. This rock system is primarily composed of igneous rocks and is distinct from the later rock systems that host coal deposits and exhibit metamorphic sedimentary characteristics.

Landforms of Chalk: Characteristics and Features

Chalk is a soft, white, porous sedimentary rock composed of the mineral calcite. It is formed from the remains of microscopic planktonic algae and foraminifera that lived in the warm, shallow seas of the Cretaceous period. The landforms of chalk are rather different from those of other limestones due to their unique characteristics and features.

Statement 1: The landforms of chalk are rather different from those of other limestones.

- Chalk is a soft, porous rock that weathers easily and is susceptible to erosion by water, wind, and ice.
- Chalk is usually found in the form of a plateau or escarpment, with steep, white cliffs facing the sea and gentle slopes inland.
- Chalk forms distinctive landforms such as caves, arches, stacks, and blowholes due to its solubility in rainwater and the erosive power of the sea.

Statement 2: There is little or no surface drainage and valleys which once contained rivers are now dry.

- Chalk is a porous rock that allows rainwater to soak through quickly, rather than forming surface runoff.
- As a result, there is little or no surface drainage on chalk landscapes, and river valleys that once contained water are now dry.
- This has led to the formation of dry valleys or coombes, which are steep-sided, narrow valleys with a flat floor that may contain a small stream or pool.

Statement 3: These are often called coombes.

- Coombes are a characteristic feature of chalk landscapes, but they can also be found on other types of rock.
- The word "coombe" comes from the Old English word "cumb", which means "valley" or "hollow".
- Coombes are often used for grazing animals or for growing crops such as wheat or barley.

Conclusion

All three statements are correct. The unique characteristics of chalk, such as its solubility, porosity, and susceptibility to erosion, have led to the formation of distinctive landforms and features, including dry valleys or coombes. These features are characteristic of chalk landscapes and have important ecological and agricultural significance.

Answer:

Rocks That Make Up the Crust of Earth

The crust of the Earth is made up of various types of rocks, but some of them make up for large portions of it. These rocks are:

1. Granitic rocks
2. Basaltic rocks

Explanation:

Granitic rocks are igneous rocks that are light-colored and have a coarse-grained texture. They are formed from the slow cooling of magma beneath the Earth's surface. They are found in the continental crust and make up a large portion of it.

Basaltic rocks, on the other hand, are dark-colored igneous rocks that have a fine-grained texture. They are formed from the rapid cooling of lava on the Earth's surface. They are found in the oceanic crust and make up a significant portion of it.

Pumice rocks and obsidian rocks are also types of igneous rocks, but they do not make up large portions of the Earth's crust. Pumice rocks are formed from the rapid cooling of lava that is rich in gas bubbles, while obsidian rocks are formed from the rapid cooling of lava that is rich in silica.

Conclusion:

Therefore, the correct answer to this question is option 'B' - 1 and 2 only, as granitic rocks and basaltic rocks make up for large portions of the Earth's crust.

Himalayan region and its poor mineral resources

There are several factors that contribute to the Himalayan region being poor in mineral resources. However, the most significant reason is the complex rock structure in the region.

Complex rock structure

The Himalayan region is characterized by a complex geological history, resulting in the formation of diverse rock types and structures. The region is mainly composed of metamorphic and sedimentary rocks, which are less likely to contain significant mineral deposits compared to other types of rocks such as igneous rocks. Metamorphic rocks are formed through the transformation of pre-existing rocks under high pressure and temperature conditions, which often leads to the loss of mineral resources.

Unfavorable terrain and adverse climatic conditions

While the undulating terrain and adverse climatic conditions in the Himalayan region certainly pose challenges for mineral exploration and extraction, they are not the primary reasons for the region's poor mineral resources. These factors may make it difficult to access certain areas and conduct mining operations, but they do not directly impact the presence or absence of mineral resources in the region.

Crystalline rocks and mineral resources

The statement mentioned that the Himalayan region is made up of crystalline rocks, which do not hold mineral resources anywhere in India. This is incorrect. Crystalline rocks can indeed contain mineral resources, although their presence and abundance vary from region to region. Crystalline rocks, such as granite and gneiss, can host valuable minerals such as gold, silver, copper, and tin. However, in the case of the Himalayan region, the primary reason for the lack of mineral resources is the complex rock structure rather than the presence of crystalline rocks.

In conclusion, the Himalayan region's poor mineral resources can be attributed to its complex rock structure, which is dominated by metamorphic and sedimentary rocks. While other factors such as unfavorable terrain and adverse climatic conditions might pose challenges for mineral extraction, they are not the main reasons for the region's limited mineral resources.

Mount Aso is located in Japan and is an active volcano. However, the statement that it was an active volcano a few decades back, but is an inactive volcano now is incorrect. Therefore, statement 1 is incorrect.

The correct statements about Mount Aso are:

Location:
- Mount Aso is located in Japan.

Activity:
- Mount Aso is an active volcano.
- The explosions in Mount Aso can be of high intensity at times.

Therefore, the correct answer is option 'D' (2 only).

Sandstone is a sedimentary rock formed by sedimentation of sand grains.

< b="" />Explanation:< />

The correct answer is option 'D', neither of them.

< b="" />Statement 1:< />
The statement is correct. When two corries cut back on opposite sides of a mountain, knife-edged ridges are formed called aretes. A corrie is a bowl-shaped hollow found on the side of a mountain, formed by glacial erosion. As the glaciers move down the mountain, they erode the sides of the corrie, creating steep knife-edged ridges called aretes. These aretes are often narrow and sharp, resembling the edge of a knife.

< b="" />Statement 2:< />
The statement is incorrect. When three or more cirques cut back together, their ultimate recession will not necessarily form an angular horn or pyramidal peak. A cirque is a bowl-shaped hollow found at the head of a glacier, formed by glacial erosion. As the glaciers move down the mountain, they erode the sides and bottom of the cirque, creating a steep-sided hollow. If three or more cirques cut back together, they may form a broad, rounded peak known as a horn. This is characterized by steep slopes on all sides. However, the ultimate shape of the peak will depend on various factors such as the nature of the rock, the direction of glacial movement, and the erosional processes involved. It is not necessary that it will always form an angular horn or pyramidal peak.

Therefore, both statements are not correct.

On the limestone's surface are numerous swallow holes, which are small depressions carved out by solution where rain-water sinks into the limestone at a point of weakness. They are also known as sinkholes. Gaping Ghyll in Yorkshire is a fine example. These holes grow in size through continuous solvent action.

Explanation:

The correct answer is option D, neither of them. None of the statements is correct.

Let's analyze each statement:

1. By plucking, the glacier scratches, scrapes, polishes, and scours the valley floor with the debris frozen into it.

Plucking is a process by which a glacier erodes the underlying rocks by freezing onto them and then pulling them out as the glacier moves. However, plucking does not involve scratching, scraping, polishing, or scouring the valley floor. These processes are more closely associated with abrasion, which is the grinding action of rocks and debris carried by the glacier against the valley floor. Plucking and abrasion are distinct processes, and the statement incorrectly combines the two.

2. By abrasion, the glacier freezes the joints and beds of the underlying rocks, tears out individual blocks, and drags them away.

Abrasion is the process by which rocks and debris carried by a glacier scrape and grind against the valley floor, causing erosion. However, the statement is incorrect in stating that the glacier freezes the joints and beds of the underlying rocks. Freezing of joints and beds is associated with frost wedging, which is a process that occurs in cold climates when water seeps into cracks in rocks and freezes, causing the cracks to widen and eventually break apart. The tearing out of individual blocks and dragging them away is more closely associated with plucking, not abrasion.

In summary, statement 1 incorrectly combines plucking and abrasion processes, and statement 2 incorrectly attributes freezing of joints and beds to abrasion. Therefore, neither of the statements is correct.

Soil creep indicates slow movement while solifluction is fast movement.

The correct answer is option 'D' - Deccan Traps.

Explanation:
The Deccan Traps is a large volcanic province located in west-central India. It is composed of multiple layers of solidified basalt lava flows. The rocks of the Deccan Traps were formed during the Late Cretaceous period, approximately 66 million years ago.

Formation of the Deccan Traps:
1. Geological Activity: The formation of the Deccan Traps can be attributed to intense volcanic activity that occurred during the breakup of the supercontinent Gondwana.
2. Massive Eruptions: The volcanic activity resulted in massive eruptions that released vast amounts of basaltic lava onto the surface.
3. Lava Flows: The lava flows spread over an area of approximately 500,000 square kilometers, covering the present-day states of Maharashtra, Madhya Pradesh, Gujarat, and Karnataka.
4. Layered Structure: Over time, the successive eruptions led to the formation of multiple layers of solidified lava flows, creating a distinctive layered structure.
5. Thickness and Extent: The Deccan Traps cover an immense thickness of up to 2,000 meters and are considered one of the largest volcanic provinces in the world.

Importance of the Deccan Traps:
1. Geological Significance: The Deccan Traps hold immense geological significance as they provide valuable insights into the Earth's history, climate changes, and mass extinctions.
2. Mass Extinction Event: The timing of the Deccan Traps' formation coincides with the mass extinction event that resulted in the extinction of the dinosaurs. It is believed that the volcanic activity and the release of gases and aerosols had a significant impact on the global climate, contributing to the extinction event.
3. Mineral Resources: The Deccan Traps also contain various mineral resources, including basalt, granite, and limestone, which are important for construction and industrial purposes.

In conclusion, the rocks of the Deccan Traps in India were formed the earliest among the given options. The intense volcanic activity during the Late Cretaceous period led to the deposition of multiple layers of solidified basalt lava flows, creating the distinctive geological formation known as the Deccan Traps.

Factors Aiding the Weathering of Rocks

Weathering refers to the process by which rocks are broken down into smaller fragments or transformed into different minerals through physical, chemical, and biological processes. Several factors contribute to the weathering of rocks. The correct answer, option 'D', states that all of the following factors aid in the weathering of rocks:

1. Intense heating during the day and rapid cooling at night:
- Temperature changes play a significant role in the weathering of rocks. When rocks are exposed to intense heating during the day, they expand. As a result, cracks and fractures develop within the rocks.
- At night, the rapid cooling causes the rocks to contract. This contraction further enhances the development of cracks and fractures. Over time, these cracks and fractures become pathways for water and other weathering agents to penetrate deeper into the rocks, accelerating the weathering process.

2. Pore pressure of water seeping into rocks:
- Water is one of the most important agents of weathering. When water seeps into rocks, it exerts pressure on the rock material, known as pore pressure.
- The pore pressure of water can weaken the rocks, especially if the water freezes and expands within the rock crevices. This process, known as frost wedging, causes the rocks to crack and break apart.

3. Thawing of rocks:
- Thawing refers to the process of melting frozen water within rocks. When water freezes within the rock crevices, it expands, exerting pressure on the surrounding rock material.
- During thawing, the ice melts, releasing the pressure within the rock. This repeated freezing and thawing cycle weakens the rocks, leading to the development of cracks and fractures.

In summary, all three factors mentioned in the given options contribute to the weathering of rocks. Intense heating and rapid cooling lead to thermal expansion and contraction, pore pressure of water seeping into rocks causes frost wedging, and the thawing process weakens the rocks. These processes eventually break down the rocks into smaller fragments, facilitating the further breakdown and transformation of the rocks through weathering processes.

Answer:

Factors responsible for changes on Earth's surface:

There are several factors responsible for bringing changes on the surface of the Earth. Some of the major factors are discussed below:

1. Tectonic forces:

Tectonic forces include processes like plate tectonics, earthquakes, volcanic eruptions, and mountain building. These forces are responsible for the creation of new landforms and the destruction of existing ones. Plate tectonics is the key process that drives the movement of the Earth's crust.

2. Gravitational force:

The gravitational force of the Earth is responsible for many changes on its surface. It causes erosion, weathering, and mass wasting. Erosion is the process by which the surface of the Earth is worn away by the action of water, wind, or ice. Weathering is the breakdown of rocks into smaller pieces due to the action of weather. Mass wasting is the downhill movement of soil and rock under the influence of gravity.

3. Electromagnetic radiation:

Electromagnetic radiation from the sun is responsible for many changes on the Earth's surface. It causes weather patterns, ocean currents, and the growth of plants. The sun's energy is also responsible for the water cycle, which is the process by which water evaporates from the surface of the Earth and is later returned as precipitation.

Correct answer:

All of the above (1, 2, and 3) are responsible for bringing changes on the surface of the Earth.