The Dravidian Era marks the beginning of life on the earth surface and hence coincides with the Primary Epoch of the geological history. It is supposed to begin with the Cambrian period (600 m.y. ago) and lasted up to Middle Carboniferous period (300 m.y. ago).
The formations of this era are almost absent in the Peninsular region except some deposits of the Lower Permian period near Umaria in Rewa and possibly a part of the Upper Vindhyan system belonging to the Cambrian period. While the Peninsula witnessed a period of quiescence during this era due to persistent epeirogenic uplift of the country, the extra-peninsula underwent movements of subsidence and developed marine conditions in certain restricted areas. For the sake of study the rocks belonging to this era are grouped under the Cambrian, Ordovician, Silurian, Devonian and the Lower and Middle Carboniferous Systems.
The Cambrian rocks including shales, sandstones, slates, clays, salt marl etc. are found in Baramula and Anantnag districts and Pirpanjal area in Kashmir; Spiti district in Himachal Pradesh; the Salt Range in Pakistan and the northern Shan state of Myanmar.
The rocks of the Ordovician System are mainly found in the Lidar valley and the Handwara basin in Kashmir, the Spiti basin in Himachal Pradesh and N. Shan state in Myanmar. Here main rocks include quartzites, sandstones, shales and limestones containing a number of fossils.
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The outcrops of the Silurian System are mainly found in the Shamsha Abri in Handwara and the Liddar valley in Anantnag (arenaceous shales, sandstones and limestones), the Spiti area of Himachal Pradesh (limestones and dolomites); and Shan state of Myanmar (limestone’s and shale’s).
The Devonian system consists of a great thickness of quartzites both in the Liddar valley and in the Pirpanjal and in Spiti. The quartzite (known as Muth quartzite) is a thickly bedded, bluish-white, hard and compact rock showing abundant cross breeding.
The Lower Carboniferous System includes Syringothyris limestones (in the Liddar valley) and the Mulh quartzites of the Lipak series (the Spiti basin). Similarly the Middle Carboniferous rocks include Fenestella shales (in the Liddar valley) and shales and quartzites of the Po series (in Spiti area). In Spiti area the shales have been intruded by dykes and sills of doleritc and are metamorphosed in the contact zone. The Carboniferous rocks in the N. Shan states (Myanmar) are called the Plateau limestone.
The unfossiliferous sedimentary rocks of the Palaeozoic age consisting of phyllites and quart/Kes and called Tanawal series (Kashmir) which are overlain by a conglomerate bed called the Tenaki conglomerate.