A submarine canyon as the cause of a mud volcano - Liuchieuyu Island in Taiwan

In this paper, based on 3.5 kHz, UNIBOOM and conventional seismic data, we propose a model for the creation of Liuchieuyu Island, a near-shore mud volcano off the southwestern coast of Taiwan. In support of this model, we also discuss the relationship between a nearby submarine canyon (Kaoping Submarine Canyon) and the mud diapirs and mud volcanoes in the region. Seismic data suggest that Liuchieuyu was originally a mud diapir with a thick, continuous accumulation of sediments on its upper surface. This sediment load or overburden prevented unconfined growth of the underlying mud diapir, while simultaneously acting as a seal that trapped gas and formed a high-pressure zone. However, Kaoping paleo-canyon eroded these overlying sediments, and the overburdening pressure was reduced. in consequence, the mud diapir rose up to the sea floor to become a mud volcano, the uppermost part of which is present-day Liuchieuyu Island. The formation of this island in the path of the paleo-canyon also diverted the channel of the canyon to its present location. (C) 2001 Elsevier Science B.V. All rights reserved.