Tectono–sedimentary and climatic setup for Dhosa Sandstone Member (Chari Formation) of Ler dome, Kachchh, western India

Abstract

The Ler Dome situated in the south of Bhuj District, Kachchh, holds a well exposed Dhosa Sandstone Member which is a unit of Chari Formation. Petrographical studies of the sandstones exposed in the river section near Ler Village were carried out to analyse the petrofacies, tectono–provenance and palaeoclimate. The Dhosa Sandstones are composed dominantly of monocrystalline and variable amount of polycrystalline quartz, potassium and plagioclase feldspars with meta–sedimentary rock fragments. The identified petrofacies suggest a hybrid continental block–cum–recycled provenance comprising granite–gneiss with metamorphic supra crustals, exposed in the craton interior. The source rocks were exposed in the early stage of thermal doming prior to incipient rifting and drifting associated with Gondwanaland breakup. Sediments underwent short transportation under moderate relief condition and humid–semi humid to temperate climate, complying with the climatic setup of this region during the Jurassic times.