“It’s commonly said that we know more about the surface of the moon than we do about the bottom of the ocean,” said Aurora Elmore of the National Oceanic and Atmospheric Administration.
A recent discovery proved the truth of this maxim: A mountain taller than Sandstone Peak, the tallest peak in the Santa Monica Mountains, has been found in the ocean not far from Northern California.
The 3,300-foot seamount, or seamount, was found by an unmanned marine mapping vehicle about 200 miles offshore during an expedition.
Beginning last summer, the Saildrone Surveyor – billed as the “world’s largest unmanned ocean mapping vehicle” – spent several months surveying the Aleutian Islands of Alaska and the ocean off California in an expedition funded by NOAA and the Bureau of Ocean Energy Management to explore.
The vehicle has charted more than 13,000 square nautical miles during its expedition.
“If [the seamount] was found, people were really excited that there was a big feature that no one had known before and that hadn’t been mapped in detail,” said Elmore, cooperative institute director at NOAA, in an interview with The Times.
The discovery was remarkable for a number of reasons, Elmore explained – the sea mount was found in an area where features are unusual and it has an unusual shape.
“There are other seamounts along the California coast,” she said, “none in this exact region, but some to the north and to the south.”
In addition, seamounts are commonly shaped like mountains on land, with sloping sides leading to a peak. But the one discovered by Saildrone more closely resembles a butte found in the deserts of the Southwest.
Its sides are sheer and vertical, and on its top is a 100-foot-deep caldera.
Elmore said researchers don’t know why or how the seamount got its cylindrical shape, but he said it was most likely a volcanic formation.
“We would need to do more testing and go back and collect geological samples and sediment samples to better understand the environment that the seamount is in and how it might have formed,” she said.
Mapping the seafloor for features like seamounts and canyons is important not only for finding geological hazards but also for ecological reasons, Elmore said.
“There are species, particularly fish, that prefer to live at a certain depth of water and they hop from one seamount to another,” she said. “Without the Seamount’s unique ecosystems, they wouldn’t have enough to eat; They might not be in their preferred depth range.”
Deep-sea fisheries could use the information to find new fishing grounds, she said.
The recent discovery “is just a really good example of all the things we don’t know about the seafloor yet,” she said, noting that about 50% of the seafloor in US territorial waters is uncharted.
“We don’t even have a general idea of what’s down there,” Elmore said. “So I think this is kind of a reminder to all of us in marine sciences about how much there is still to explore and discover in the deep sea.”
Source : www.latimes.com