Aravalli Craton

Aravalli Craton

Aravalli craton is consisted of Aravalli, Delhi and Marwar Supergroups.

Aravalli basin is oldest which was deposited in paleoproterozoic overlies the Banded Gneissic Complex. Succession of Aravalli basin:

Jhamarkotra formation have phosphorite deposits and stromatolites.

Delhi Fold belt and Marwar basin

During mesoproterozoic, Aravalli craton and Bundelkhand craton converged, Bundelkhand craton subducted beneath Aravali which resulted in formation of Delhi fold belt.

Delhi fold belt is composed of slate, phyllite, quartzites and limestone. Stratigraphy of Delhi supergroup is divided into 2 groups namely Alwar group, the lower one and Ajabgarh group which is overlying the Alwar group. They are seperated by Kushalgarh limestone.

Delhi SG stratigraphy

Ajabgarh group         Phyllite, slate and schists

_________  Kushalgarh limestone _______

Alwar group              Quartzites, grits & congl.

The subduction resulted in formation of back arc basin which is called Marwar basin. It is of Neoproterozoic age. 

In summery, Aravalli which deposited in paleoproterozoic, went in convergent setting with Bundelkhand craton, resulted in formation of Delhi fold belt during mesoproterozoic. As we know, during subduction, a back arc basin also opens on overriding plate and that's exactly happened here. The basin opened was Marwar basin.

Stratigraphy of Marwar basin begun with Neoproterozoic formation Jodhpur Sandstone overlying the Malani rhyolites.

Hansneer evaporites are important as they contains deposits of gypsum and halites. Nagaur formation have ichnofossils (trace fossils) of trilobites.