An occurrence of similar to 74 ka Youngest Toba Tephra from the Western Continental Margin of India

A dispersed volcanic ash layer was recovered at similar to 300 cm depth in a 5.52 m long sediment core collected at a latitude 9 degrees 21 'N and lon gitude 71 degrees 59 'E from a water depth of 2300 m on the Western Contine ntal Margin of India (WCMI). Glass shards from ash layer were studied for m orphology, major, trace and rare earth element concentration to trace the s ource, Bubble wall junction-type morphology of glass shard suggests magmati c origin. shards have high SiO2 (77%) and total alkalis (8.5%), indicating rhyolitic composition. The major, trace and rare earth element composition of these glass shards are indistinguishable from that of Youngest Toba ash of similar to 74 ha from the Northern Sumatra and confirm as the source. Th e new occurrence of Youngest Toba Tuff from the WCMI, Central Indian Ocean Basin and South China Sea Basin suggests a reassessment of the ash volume a nd global climatic implications.