Middle Cretaceous carbonate build-ups and volcanic seamount in the Shyok suture, Northern Ladakh, India

Along the Shyok suture zone in northern India, a similar to 200 m thick lim estone succession has been identified as a carbonate platform margin with b uild-ups. This limestone succession is directly overlying volcanic rocks of island arc affinity. The partly recrystallized reefal limestone which rest s on a volcanic seamount or ridge contains abundant rudists, corals, gastro pods, algae and a rich orbitolinids assemblage of Late Aptian-Early Albian age. This faunal assemblage reflects a shallow-water tropical environment f or the carbonate build-ups and also shows a close affinity with those recor ded from the Yasin Group in north-western Pakistan. The presence of Late Ap tian Horiopleura, Radiolitidae and different forms of Orbitolinae and other microfaunal assemblage in the reefal limestone, dates the underlying volca nic edifice as Middle Cretaceous or older. Rudists, nerineids, corals and foraminifers of Lower Cretaceous age are wid ely distributed as a reefal framework all along the tropical and subtropica l Euro-African-Asiatic regions of the northern margin of the Tethys. Howeve r, prior to our findings, the Cretaceous carbonate build-ups associated wit h submarine volcanism have only been reported in the Caribbean, Sicily in I taly, Yasin in Pakistan and from dredged samples from a seamount in the cen tral Pacific region.