PORT-OF-SPAIN, Trinidad – A mud-spewing fissure in the ocean floor has given birth to a tiny Caribbean island and is posing a threat to small boats.
The island, breaching a few inches above the ocean's surface and stretching 500 feet long, was discovered recently roughly five miles northeast of Trinidad, said Roderick Stewart, a seismologist at the University of the West Indies in St. Augustine.
An advisory has been issued for small boats, which could lose buoyancy because of gas bubbling up from the underwater fissure or run aground in the mud.
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The danger may be short-lived. Large waves are washing away the mud and the fissure may fade.
It is not the first time such tiny, short-lived islands have emerged off the coast of the twin-island Caribbean nation of Trinidad and Tobago. Temporary islands also were formed in 1964 and 2001.
The islands are created by what scientists call "mud volcanoes," a varying mixture of water, sediment and compressed pockets of natural gas that usually emerge along fault lines.
A mud volcano even erupted on land here in the late 1990s, inundating part of a village. No one was injured.
Sediment deposits from rivers in nearby South America contribute to the phenomenon.