Multiple ash layers in late Quaternary sediments from the Central Indian Basin

A comparison with the published data on volcanic tephra in and around the Indian Ocean indicate the shard rich horizon (SRH) of 70-75 ka to resemble the Younger Toba Tuffs (YTT), while the other volcanic horizons that were deposited during different time periods do not correlate with any known marine or terrestrial records. These tephra layers have produced a tephrostratigraphic framework across the tectonically and volcanically complex regions of the CIB. Due to the lack of terrestrial equivalents of these tephra, it is hypothesized that the newly found volcanic horizons may have been derived from submarine volcanic eruptions. Multiple layers of submarine volcaniclastic deposits found at water depths as great as 5300 m reaffirm the growing belief that submarine phreatomagmatic eruptions are much more common in the intraplate region of the Indian Ocean than previously reported.