Presence of collumnar stromatolites in Jhamarkotra.

Probably the earliest forms of life evidences available Stromatolites are of great economic importance too. Stromatolites are the fossils of cyanobacteria aka blue-green algae, in the case of jhamarkotra of species Collerici columnaris. These stromatolites occur in a dolomitic matrix. Economically this fossil is known by the name of phosphorite or more commonly rock-phosphate as these are rich in phosphate content as these alga fix phosphates from their surrounding environment. Their presence also indicates marine palaeo-environment. As photography in this mine is strictly prohibited this photograph hails from Stromatolite Park Jhamarkotra Raj. Age -Lower Proterozoic.

Amygdaloidal Structure seen in Basalts Isarthuni Ratlam.

Igneous Rocks can be of two types extrusive and intrusive . Extrusive rocks come out from inside of the earth and cool down on the surface therefore has very less time for formation of crystals. As the gases stored inside the magma have no time to escape out they form voids inside the rock mass, later these voids are filled with secondary depositions forming amygdaliods and the rock thus formed is said to have a amygdaloidal structure.

Deccan basalts in Isarthuni Ratlam.

Hexagonal Joints seen in Basalts of Malwa group of the Deccan Traps. These joints develope as the lava cools down and forms three weak zones in between.Pic of Isarthuni Ratlam M.P.