Rajasthan : Geological Structure

raj geologyGeologically Rajasthan comprises rocks from oldest Archean rocks to recent alluvium formations .

The oldest formations are known as Banded Gneissic Complex exposed in central and southern Rajasthan.

The Aravalli hill range dividing the State diagonally is made up of precambrian rocks of Aravalli and Delhi Super group comprising the metamorphosed gneisses, schists, marble, quartzite, calc silicate, ultra basic, acidic and basic intrusive rocks. This is known as Delhi fold belt and is an important horizon for base metals, other metallic and non-metallic minerals.

The eastern and southeastern parts of the State are occupied by rocks of Vindhyan Super group mainly forming a plateau of sandstone, shale’s and limestone.

In the southern part Deccan trap formation of cretaceous age are exposed.

In west :-

  • near jodhpur there are reserves of sandstone
  • near jalore-siwana there are reserves of granite
  • malani there are reserves of rayolite

in north

  • dholpur and karoli- red sanstone
  • Jaisalmer – steel grade lime stone

The Aravalli metallogenic province of Rajasthan is the most important geological province for base metal and gold deposits. The province contains the world class Rampura-Agucha Lead-Zinc deposit along with several large deposits of Lead and Zinc in Rajpura-Dariba and Zawar belts. In addition, there are a number of deposits in Deri-Basantgarh belt. Since the last decade, several gold deposits have been proved in the southern part of the province in Banswara district.

Mineral Potentiality: The State is geologically so endowed that it become a veritable repository of minerals. Rajasthan is fortunate enough to have a wide spectrum of mineral deposits. There are about 58 different kind of major and minor minerals produced in the State, contributing an annual revenue of more than 3088 crores and more than 5953 crores from petroleum.

Rajasthan is the sole producer of garnet (gem variety), jasper and wollastonite.

Almost entire production of zinc (concentrate), calcite, asbestos and gypsum in the country was reported from Rajasthan. Besides,

Rajasthan is the leading producer of ball clay (70%), feldspar (36%), fluorite (graded) (59%), Kaolin (44%), lead concentrate (89%), ochre (90%), phosphorite (90%), silver (81%), steatite (76%), barytes (32%), copper (32%), quartzite (33%) and silica sand (21%).