Pillow Basalts of Early Permian Panjal Traps from Guryul Ravine, Kashmir, JK, India: A Geoheritage Site

Abstract

Geoheritage aims to protect and preserve the geological sites having inimitable geological, scientific, and educational significance. India is bestowed with excellent geological structures, geomorphic features, and rock types varying in age from Archaean to Holocene. Permian Panjal traps (North-west of India) present a first-class hope to understand the multifarious transport of magma from mantle to crust, petrochemical growth of igneous rocks, and the development of ore deposits related to magmatic activity (such as Fe–Ti–V, Cr, Ni-Cu-PGE). These volcanic rocks are important in understanding the evolution of Neotethys ocean. Panjal traps (for being the largest part of the Himalayan Permian magmatic region) would be helpful in understanding the petrogenesis of the Himalayan Permian mafic and silicic magmatic rocks which is debatable at global level. The present study aims to propose the pillow basalts of Panjal traps exposed at Guryul Ravine, Kashmir, as a Geoheritage site. On the bases of length of major axis, studied pillows are grouped into normal class (having < 100-cm length of major axis) and mega class (having > 1 m length of major axis). The formation of undersized pillows having flat surfaces and continuous chilled crusts has been attributed with uniform and restricted stretching of the outer crust. The studied pillows show different shapes like spherical, oval and elongated to irregular and have radial joint patterns which have been filled at later stages by secondary minerals such as calcite and chlorite. Spaces between / among adjacent pillows are occupied by cements of hydrothermal origin and secondary minerals (like chlorite, calcite, and hyaloclastite breccias). The preservation of these pillow basalts of Panjal traps would be highly beneficial to support the evidence of magma eruption under marine environment, magma–water interaction studies, petrological evolution of Panjal traps, and sights related to tectonic setting of the area during the Permo-carboniferous period. Hence, these pillow basalts, in the vicinity of Permian–Triassic boundary section, at Guryul Ravine, form the potential area to be promoted as geo-heritage site.