A volcaniclastic deep-sea fan off La Reunion Island (Indian Ocean): Gradualism versus catastrophism

作者：Saint Ange Francky^*; Savoye Bruno; Michon Laurent; Bachelery Patrick; Deplus Christine; De Voogd Beatrice; Dyment Jerome; Le Drezen Eliane; Voisset Michel; Le Friant Anne; Boudon Georges

来源：Geology, 2011, 39(3): 271-274.

DOI：10.1130/G31478.1

A new geophysical data set off La Reunion Island (western Indian Ocean) reveals a large volcaniclastic submarine fan developing in an open-ocean setting. The fan is connected to a torrential river that floods during tropical cyclones. Sediment storage at the coast is limited, suggesting that the sediments are carried directly to the basin. The fan morphology and turbidites in cores lead us to classify it as a sand-rich system mainly fed by hyperpycnal flows. In the ancient geological record, there are many examples of thick volcaniclastic successions, but studies of modern analogues have emphasized mechanisms such as debris avalanches or direct pyroclastic flow into the sea. Because the Cilaos deep-sea fan is isolated from any continental source, it provides information on architecture and noncatastrophic processes in a volcaniclastic deep-sea fan.

• 出版日期2011-3