Introduction to earth's landform - class-IX

Major changes in the climate of the world with a shift to relatively warm conditions were noticed around 12,000 years ago. As a result, grasslands developed in many regions. This resulted in the increase in the herbivorous animals like deer, antelope, goat, sheep and cattle

Rift Valley, in terms of the theory of plate tectonics, occur in divergence zones were two of the various lithospheric plates that make up the Earth’s surface are separating. Numerous submarine rift valleys have been discovered along the crests of the large ridges that run throughout the Earth’s oceans. These ridges are centers of seafloor spreading: areas where the magma from the mantle is welling up, cooling to form the new oceanic crust, and is moving away from the crests in either direction.

A peninsula is a landform surrounded by water on the majority of its sides while being connected to a mainland from which it extends. The surrounding water is usually understood to be continuous, though not necessarily named as a single body of water.

Rift Valley, in terms of the theory of plate tectonics, occur in divergence zones where two of the various lithospheric plates that make up the Earth’s surface are separating. Numerous submarine rift valleys have been discovered along the crests of the large ridges that run throughout the Earth’s oceans. These ridges are centres of seafloor spreading: areas where magma from the mantle is welling up, cooling to form new oceanic crust, and is moving away from the crests in either direction.

The intense heat in the earth's interior does not travel to the surface because rocks are bad conductors of heat. The internal heat of the earth therefore melts the rock and keeps the asttenosphere which is underneath the crust in a semi molten state. This leads to several conditions which cause landform development on the surface of the earth. A landform is a natural feature of earth surface.

Orogeny refers to forces and events leading to a large structural deformation of the Earth's lithosphere (crust and uppermost mantle) due to the interaction between tectonic plates.

Orogeny is the primary mechanism by which mountains are built on continents. The word orogeny comes from Ancient Greek means building mountains.

<p>Earth’s

Movement is the prime factors controlling Land Form Development.
Landform, whether large or small result from the interaction of
certain forces, they accomplish their work by various means of
processes, which may be described as geologic, Climatic and biologic
and these processes bring about the changes in the Earth’s surface
which may be classified as

(I) Long Period Changes (Man Is unable to notice this change)

(II) short period Changes.

The forces coming from within the earth are called as Endogenetic forces which causes two types of movement in the earth viz

(I) Horizontal movements

(II) Vertical movements.

These forces derive their energy from changes such as radioactivity, chemical recombination, expansion or contraction or displacement of molten materials that occur in the interior of the earth. This group of forces may be called as Tectonic forces which manifests through Processes Called Diastrophism and Volcanism

Sudden and become disastrous When they occur in densely populated localities. These forces work very quickly and their results are seen within minutes. Movements, caused by sudden-Endogenetic forces coming from deep within the earth cause sudden and rapid events that cause massive destructions at and below the earth’s surfaces. Such events like volcanic eruptions and earthquakes, are called ‘EXTREME EVENTS’ and become disastrous hazards when they occur in densely populated localities.

Epirus is a historical and geographical region of the southwestern Balkans, straddling modern Greece and Albania.

The name Epirus meaning "continent". It may also refer to extending inland from a continental margin.

In the youthful stage of fluvial cycle of erosion V-shaped valley are formed. It is steep-walled valley having narrow depression. Both the valley sides meet together at valley floor and water always touches the valley. V-shaped valleys are the result of accelerated rate of downcutting of river.

• Rivers carry a large amount of sediments with them. When rivers deposit these deposits near their mouths, before falling into to sea, a landform is formed that is known as delta. It has rich soil and the river in delta gets bifurcated into a number of streams making deltas highly fertile.
• Formation of the delta is influenced by the amount and rate of sedimentation, shape and slope of the coast and also by the waves striking at the coast. Hence all options are correct.

The valley is formed by the rift or faulting. It is a liner shaped low land between several highlands or mountain ranges created by the action of geologic rift or fault. 

Zojila Pass is a high mountain pass in the Himalayas, located in the Indian union territory of Ladakh. It serves as a vital link between the Kashmir Valley and the Ladakh region.

4500 meters

With an average elevation exceeding 4,500 meters (14,800 ft), the Tibetan Plateau is sometimes called "the Roof of the World" and is the world's highest and largest plateau, with an area of 2,500,000 square kilometers  (about five times the size of Metropolitan France).

• At one point of time, all the landmass on Earth was united as one mega continent called Pangea and whole water bodies were also unified called Panthalassa.
  
• After that, the Pangea got bifurcated into the northern part as Laurasia and southern part as the Gondwanaland.
• Peninsular India was part of Gondwanaland which moved northwards to unite with rest of India. Thus the right answer is B.