Welded Tuff, Jodhpur District, Rajasthan
Welded Tuff, Jodhpur District, Rajasthan in the Jodhpur Fort hill area occurs within the terrace like weathered Malani volcanics.
The welded tuff, is a product of emanations, that spurted out from volcanic vents and were carried away by air to settle down.
They are composed of glass, quartz and feldspar. On cooling they develop joints which which gives rise to columns and terraces.
The Malani rhyolites comprise pink, maroon, brown, purple, grey and green rhyolite separated by tuff, welded tuff and pyroclastic rocks.
The columnar joints developed are rectangular to hexagonal, attaining a length of 30m or more at places. It is overlain by deep purple
coloured porphyritic rhyolite.The pyroclastics are intermixed with lava representing the final phase of emanations.
Jodhpur is situated SW of Jaipur and is well connected by State Highways. The Northern Railway Main Line and Northern Railway Phalodi
Branch passes through Jodhpur Town. It is also approachable by air. The welded tuff outcrop is about 100 m on the right side of the
road before the Mehrangarh Fort while proceeding from the town.