Here is your short paragraph on the geological regions of India!
The geological structure, which includes the arrangement and deposition of rocks in the earth’s crust, plays a dominant role in determining the relief of land and nature of soil.
It also helps in knowing about the vast mineral wealth buried beneath the earth’s surface.
As such, study of geological structure plays a vital role in agricultural and industrial growth and in the economic prosperity of the country. For example, the vast alluvial Indo-Gangetic plain has very fertile soils and is extremely useful for agriculture. But it is almost completely devoid of any mineral deposits worth the name.
On the other hand, igneous and metamorphic rocks of the peninsular plateau, especially those of the Chotanagpur plateau are very rich in mineral resources. Similarly the study of geological structure helps in land use planning, development of transport and communication lines, increasing potentials for irrigation, determining the quality and quantity of ground water resources and understanding disasters like earthquakes, volcanoes, landslides, floods, etc. Therefore, it is necessary for us to study the geology of India before we proceed to learn more about the geography of the country.
Geological Regions of India:
Geologically, India is divided into three regions, viz., (1) the Peninsular region, including the Meghalaya plateau in the north-east and the Kuchchh-Kathiawar region in the west; (2) the extra-peninsular region—the Himalayas and their eastern extensions including Andaman and Nicobar Islands and (3) the Indo-Gangetic plain, between Peninsular and extra-peninsular region.
Although the triple tectonic division of India as mentioned above is generally held valid and is readily accepted by majority of geologists, some scholars recognise only two geological divisions of India i.e. the Peninsular block and the Extra-Peninsular region comprising the Himalayan ranges and the Indo-Gangetic plain.
These macro-regions present most striking geological contrasts. The Peninsula is one of the oldest land-masses of the earth and is dominated by open senile topography. The Extra-Peninsula, on the other hand, presents the most youthful relief of the earth in the form of the Himalayas. The alluvial filled Indo-Gangetic plain presents flat, featureless and monotonous topography.
The Indian Peninsula has not undergone marine submergence since the Cambrian period and is not much affected by the tectonic forces. In contrast, the extra-peninsular region has its origin in the Tethys Sea and is prone to tectonic forces resulting in devastating earthquakes. It is a weak and flexible portion of the earth’s crust which has been folded, faulted and over-thrust.