India has practically all major physical features of the earth i.e. mountains, plains, deserts, plateaus and islands.We find different types of rocks; some are very hard like marble which has been used for
making the Taj Mahal, and some are very soft like soap stone which is used in making talcum powder. The colour of soil varies from one place to the other because soil is formed out of different types of rocks. Have you ever thought about the causes of these variations? Most of these variations are caused due to differences in rock formations.
India is a large landmass formed during different geological periods which has influenced her relief. Besides geological formations, a number of processes such as weathering, erosion and deposition have created and modified the relief to its present form.
Earth scientists have attempted to explain the formation of physical features with the help of some theories based on certain evidences. One such plausible theory is the “Theory of Plate Tectonics”. According to this theory, the crust (upper part) of the earth has been formed out of seven major and some minor plates.(Tectonic plates)
The movement of the plates results in the building up of stresses within the plates and the continental rocks above, leading to folding, faulting and volcanic activity. Broadly, these plate movements are classified into three types. While some plates come towards each other and form convergent boundary. Some plates move away from each other and form divergent boundary. In the event of two plates coming together they may either collide and crumble, or one may slide under the other. At times, they may also move horizontally past each other and form transform boundary. The movement of these plates have changed the position and size of the continents over millions of years. Such movements have also influenced the evolution of the present landform features of India.
The oldest land mass of India (peninsula part)was the part of Gondwana land. Gondwana included most of the landmasses in today's Southern Hemisphere, including Antarctica, South America, Africa, Madagascar, and the Australian continent, as well as the Arabian Peninsula and the Indian Subcontinent, which have now moved entirely into the Northern Hemisphere.The conventional currents split the crust in the number of pieces thus leading to the drifting of the Indo-Australian plate after being separated
from the Gondwana land, towards north. The northward drift resulted in the collision of the plate
with the much larger Eurasian Plate. Due to this collision, the sedimentary rocks which were
accumulated in the geosyncline known as the Tethys were folded to form the mountain system
of western Asia and Himalaya.
The Himalayan uplift of Tethis sea and subsidence of northern flank of peninsular plateau reasulted in the formation of a large basin. In due course of time this depression, gradually got filled with deposition of sediments by the rivers flowing from the mountains in the north and the peninsular plateau in the south. A flat land of extensive alluvial deposits led to the formation of the northern plains of India.
Gondwanaland, is the name given to the more southerly of two supercontinents (the other being Laurasia) that were part of the Pangaea supercontinent that existed from approximately 300 to 180 million years ago (Mya). Gondwana formed prior to Pangaea, then became part of Pangaea, and finally broke up after the breakup of Pangaea. Gondwana is believed to have sutured between about 570 and 510 Mya, thus joining East Gondwana to West Gondwana. It separated from Laurasia 200-180 Mya (the mid-Mesozoic era) during the breakup of Pangaea, drifting farther south after the split.
The land of India displays great physical variation. Geologically, the Peninsular Plateau constitutes one of the ancient landmasses on the earth’s surface. It was supposed to be one of the most stable land blocks. The Himalayas and the Northern Plains are the most recent landforms. From the view point of geology, Himalayan mountains form an unstable zone. The whole mountain system of Himalaya represents a very youthful topography with high peaks, deep valleys and fast flowing rivers. The northern plains are formed of alluvial deposits. The peninsular plateau is composed
of igneous and metamorphic rocks with gently rising hills and wide valleys.
making the Taj Mahal, and some are very soft like soap stone which is used in making talcum powder. The colour of soil varies from one place to the other because soil is formed out of different types of rocks. Have you ever thought about the causes of these variations? Most of these variations are caused due to differences in rock formations.
India is a large landmass formed during different geological periods which has influenced her relief. Besides geological formations, a number of processes such as weathering, erosion and deposition have created and modified the relief to its present form.
Earth scientists have attempted to explain the formation of physical features with the help of some theories based on certain evidences. One such plausible theory is the “Theory of Plate Tectonics”. According to this theory, the crust (upper part) of the earth has been formed out of seven major and some minor plates.(Tectonic plates)
The oldest land mass of India (peninsula part)was the part of Gondwana land. Gondwana included most of the landmasses in today's Southern Hemisphere, including Antarctica, South America, Africa, Madagascar, and the Australian continent, as well as the Arabian Peninsula and the Indian Subcontinent, which have now moved entirely into the Northern Hemisphere.The conventional currents split the crust in the number of pieces thus leading to the drifting of the Indo-Australian plate after being separated
from the Gondwana land, towards north. The northward drift resulted in the collision of the plate
with the much larger Eurasian Plate. Due to this collision, the sedimentary rocks which were
accumulated in the geosyncline known as the Tethys were folded to form the mountain system
of western Asia and Himalaya.
The Himalayan uplift of Tethis sea and subsidence of northern flank of peninsular plateau reasulted in the formation of a large basin. In due course of time this depression, gradually got filled with deposition of sediments by the rivers flowing from the mountains in the north and the peninsular plateau in the south. A flat land of extensive alluvial deposits led to the formation of the northern plains of India.
Gondwanaland, is the name given to the more southerly of two supercontinents (the other being Laurasia) that were part of the Pangaea supercontinent that existed from approximately 300 to 180 million years ago (Mya). Gondwana formed prior to Pangaea, then became part of Pangaea, and finally broke up after the breakup of Pangaea. Gondwana is believed to have sutured between about 570 and 510 Mya, thus joining East Gondwana to West Gondwana. It separated from Laurasia 200-180 Mya (the mid-Mesozoic era) during the breakup of Pangaea, drifting farther south after the split.
The land of India displays great physical variation. Geologically, the Peninsular Plateau constitutes one of the ancient landmasses on the earth’s surface. It was supposed to be one of the most stable land blocks. The Himalayas and the Northern Plains are the most recent landforms. From the view point of geology, Himalayan mountains form an unstable zone. The whole mountain system of Himalaya represents a very youthful topography with high peaks, deep valleys and fast flowing rivers. The northern plains are formed of alluvial deposits. The peninsular plateau is composed
of igneous and metamorphic rocks with gently rising hills and wide valleys.
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