Landforms and Water Bodies - Class VIII

Barkan is a crescent-shaped sand dune produced by the action of wind predominately from one direction. One of the commonest types of dunes, it occurs in sandy deserts all over the world.

Wind erosion has the greatest impact on areas with dry soil because it is easier for wind to pick up and transport dry, light soil. Characteristically, deserts have dry soil, or sand, that is easy to transport. Also, deserts often have fewer physical barriers, such as hills, trees, or other structures, that can slow the wind movement.

Erosion is the geological process in which earthen materials are worn away and transported by natural forces such as wind, water, or ice.

True,

Narmada river rises in the Amarkantaka hills in Madhya Pradesh. It flows towards the west in a rift valley formed due to faulting. Its length is about 1312 km. This river drains into the Arabian Sea. It flows through the states of Madhya Pradesh, Maharashtra, and Gujarat.

• A Rift valley is a narrow linear depression in the land surrounded by mountain ranges. It is created by a geological fault in earth's crust. The East African Rift valley which runs thousands of km long is the best example of a Rift valley in the world.

• When two plates of earth's crust move apart from each other, a long narrow depression is formed due to the sinking of ground which is called a rift valley eg. east African rift valley. Hence option C is the right answer.
• The rift valley is not formed due to river or aeolian(wind) action. Also, the slope in the rift valley is almost vertical thus very steep hence other options are incorrect.

A rift valley is a lowland region that forms where Earth's tectonic plates move apart, or rift. This is a direct result of tectonic forces, unlike V-shaped valleys (river erosion) or U-shaped valleys (glacial erosion).

The words 'ocean' and 'sea' are often used to mean the same thing. However, a sea is a small area of an ocean, usually with land on several sides.

Inland sea is a shallow sea that covers central areas of continents during periods of high sea level that result in marine transgression. The seas which are completely surrounded by land, without any outlet into the ocean is called inland sea.

The Mediterranean Sea is an extension of the Atlantic ocean. The Mediterranean Sea is connected to the Atlantic ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land. The sea was an important route for merchants and travelers of ancient times, facilitating trade and cultural exchange between peoples of the region.

Marginal seas are similar to open oceans with respect to being created by large scale geological processes, exhibiting biodiversity, and possessing layered water circulation patterns. The main difference between the two is related to depth and proximity to landmasses. The seas which are extensions of the ocean and are partially surrounded by land are known as marginal sea.

Lake Baikal in southern Russia is the world's deepest lake. It is an estimated 5,387 ft deep and its bottom is approximately 3,893 ft below sea level. It is also the deepest freshwater lake in the world.

Bay is a water body that is surrounded or demarcated by land. It is a water body that is surrounded by land on three sides. Bays can be an inlet in a lake or a larger water body. 

A gulf is a large inlet of a sea cutting deep into the landmass, typically narrower opening than a bay, though it is not observable in all geographical areas. Many important trading centers are located on gulfs. Gulfs are sometimes connected with oceans through narrow passages of water called as straits. 

Lake Baikal is situated in Russia, located in southern Siberia, between Irkutsk Oblast to the northwest and the Buryat Republic to the southeast. It is the world's deepest freshwater lake.

Lagoons is a term used for a shallow body of saltwater separated from the sea by a low dan bank or coral reef. Lagoons are commonly divided into coastal lagoons and atoll lagoons. Lagoons are the most common coastal features around many parts of the world.

Strait is a narrow stretch of water that joins two large water bodies and separates two landmasses. Strait can be formed by a body of water overflowing land that has subsided or has been eroded. 

The highest commercially navigable lake is Lake Titicaca, which lies in the Altiplano at a height of 3,810 m above sea level on the Andean border between Peru and Bolivia. It's surface covers approximately 8,300 km² and has an average depth between 140-180 m.

Bering Strait joins the Arctic Ocean and the Pacific Ocean and separates the continents of Asia and North America at their closest point. The strait averages 98 to 164 ft. in depth and at it's narrowest is about 53 miles wide. The strait was named after Vitus Bering, a Danish Captain, who sailed into the strait in 1728.

The Mississippi River is the second-longest river and chief river of the second-largest drainage system on the North American continent. It's  source is Lake Itasca in northern Minnesota and it flows generally south for 2,320 miles to the Mississippi River Delta in the Gulf of Mexico.

Chilika Lake in Odisha is the largest brackish water lagoon in India and is often cited as the largest lake in India by surface area.

The Amazon River is the largest river in the world by the amount or volume of water it carries. Its headwaters are in the Andes Mountains in Peru. It flows through the tropical forests of South America.

Chilika Lake, Pulicat Lake, and Vembanad Lake are all examples of lagoons in India. They are formed by sand bars separating coastal water from the sea.

The Damodar River flows through a rift valley in the Chota Nagpur Plateau region. This rift valley was formed due to down-warping of the crust.

Inland drainage occurs where rivers do not reach the sea but instead drain into inland lakes or disappear into the ground. The Rann of Kutch is a classic example of an inland drainage area in India.

The Narmada River flows through a well-known rift valley located between the Vindhya and Satpura ranges in central India.

The mainstream of Ganga begins at the confluence of the Bhagirathi and Alaknanda rivers in the town of Devprayag. The Bhagirathi rises at the foot of Gangotri Glacier, at Gaumukh, at an elevation of 3,893 m.

Lonar Lake (A), Toba Lake (C), and Keloed Lake (D) are all volcanic crater lakes. Bhim Tal is a lake in the Kumaun region, but it is not of volcanic origin.

Lake Superior is the largest lake in North America and also the largest freshwater lake in the world by surface area and the third-largest by volume. Its surface area is approximately 31,700 square miles. The lake is shared by the province of Ontario in Canada, and the states of Minnesota, Wisconsin, and Michigan in the US. 

The Wular lake is integral to the hydrological system of the Kashmir valley. India's largest freshwater lake, the Wular lake was formed as a result of the tectonic activity and is fed by the Jhelum river. The lake, along with its marshes, regulates the water levels and offers protection against flooding.

Lake Superior, located on the border between the United States and Canada, is the largest freshwater lake in the world by surface area.

The lithosphere is broken into several large and small segments known as tectonic plates, which move over the asthenosphere.

At a divergent boundary, tectonic plates move away from each other, often leading to the formation of new crust.