India, including Uttar Pradesh, was part of an ancient landmass known as Gondwanaland. The Gangetic plain region came into existence during the Pleistocene period, The southern plateau region is older and is an extension of the peninsular plateau.
Archaean, Vindhyan, Gondwana, Tertiary and Quaternary rock systems are found in Uttar Pradesh.
Archaean Rocks
These are the oldest geological structures found in Sonbhadra and Lalitpur.
These rocks include schist, gneiss and granite.
These rocks have probable reserves of precious minerals like uranium, diamond, etc.
The Bundelkhand gneiss is a type of Archaean rocks. It looks like granite and is marked by the presence of a coarse-grained structure.
Vindhyan Rocks
These rocks form a dividing line between the plains of the state and peninsular India. These rocks are sedimentary.
These are formed by the denudation of the cuddapah rocks and the upliftment of the deposits of the Tethys Sea.
The Kaimur series of the Vindhyan rock system is present in Bundelkhand and Baghelkhand Plateau.
These rocks are made of minerals like sandstone and limestone. These rocks are abundant in the Son river valley in Sonbhadra and Lalitpur.
Gondwana Rocks
The deposition of sediments over a long period during the Carboniferous period to the Jurassic period has led to the formation of crusted sedimentary rocks known as Gondwana rocks.
These rocks are found in the southern parts of Mirzapur, Sonbhadra, Chitrakoot and Prayagraj districts of Uttar Pradesh and are known for the reserves of coal, iron-ore, kaolin, sandstone, fireclay etc.
Son valley has deposits of coal.
Rocks of Tertiary System
The tertiary period is marked by the upliftment of depositions of the Tethys sea and the formation of the Himalayas.
The geological formations of tertiary period are important because these are credited to decide the present physiographic structure and flow patterns of the major rivers of northern India including Uttar Pradesh.
These rocks have fossils closely related to modem life forms.
Rocks of the Quaternary System
These are very recent deposits and contain fossils of living species. The formation of northern Indian plains happened during the Pleistocene period under the Quaternary rock system.
The alluvial deposits of early and middle Pleistocene are known as Bangar whereas the formations of later Pleistocene are known as Khadar. The Khadar formation still continues.
