Geological History of Jharkhand
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The history of the geological structure of Jharkhand is as old as the history of the Earth's initial crust. Geologists have divided the history of geological structure of Jharkhand into the following parts: -

(1) Archaean

Archaean rocks are the oldest rocks on earth (rocks formed by the solidification of the earth's liquid). Fossils are not found in these rocks because the organisms did not develop at that time. The rocks are divided into two parts - the Archaean sequence and the Dharwad sequence.
    The rocks of the Archaean have been formed in order of solidification from the liquid state of the earth, while the rocks of the Dharwad have been formed by erosion and deposition of the Archean rocks. Deposits of metallic minerals (iron, copper, gold, nickel etc.) have taken place on a large scale in Dharwad rocks. These rocks are found prominently in Kolhan division of Jharkhand, due to which they are known as Kolhan range in Jharkhand.

(2) Vindhyan

 The Vindhyan rocks are formed after the Kadapa sequence (found mainly in South India). In Jharkhand, the remains of the Vindhyan order are found mainly in the area of ​​the Son River. Parasnath mountain is a part of Vindhyan mountain.

(3) Carboniferous

 Gondwana has been demarcated during this period. The whole of India, including Jharkhand, was covered with sheets of snow at this time. Its remains are found in the lower parts of rivers. Its remains have been found in the 'Talcher Range' in the south eastern part of Jharkhand. After the Carboniferous glaciation, the field developed slowly in this area.

(4)Permian-Triassic sequence

 This is the post-Carboniferous phase of Himanization. There was a lot of erosion of high ground during this period. The erosion in the Sone and Damodar river basins in Jharkhand due to the rise of the Karakoram Range (Himalayas) was the most important event of this period which affected the entire drainage system of the region. Its remains are found as gravel in Dhalbhum.

(5) Gondwana sequence

 This period is also known as coal era. The saplings which were planted due to fault in the Sone and Damodar river all subsided and later they turned into coal.

* (Cretaceous) A lava erupted in Jharkhand in the Cretaceous era similar to the Deccan lava known as the Rajmahal Trap. It is widespread in Dumka, Godda and Sahebganj districts.

(6) Cenozoic sequence

By the beginning of this period, the entire Chotanagpur plateau was in a state of erosion due to erosion action. During this period, due to three successive elevations of the Himalayas, the plateau of Chota Nagpur also rose in three stages, due to which the rivers here were revived. During this period, along with the construction of the Pate region and the Ranchi-Hazaribagh plateau, the Rajmahal trap also rose. Due to this, water falls were also constructed.

(7) New deposition

In this period, due to deposition of many rivers, the land was created. The plains of Panchpargana, the lowlands of Deoghar, the Ajay Basin region, the northern and southern Koyal basins, etc. are the results of this era.