Seafloor Maps Reveal Underwater Caves, Slopes—and Fault Lines

Here are some more insights into what lies underneath the sea floor :-

Seafloor Maps Reveal Underwater Caves, Slopes—and Fault Lines

Drone ships, deep-sea robots, and better sonar are finding unknown seafloor habitats as well as volcanoes, faults, and tsunami-triggering slopes.

Schmidt Ocean Institute

Larry Mayer is headed out this week on a ship to explore the Channel Islands off the Southern California coast. Well, he’s actually exploring seafloor formations near the islands, looking for evidence that ancient peoples might have camped out in the caves as they migrated south some 15,000 years ago, a time when the sea level was 600 feet lower than today.

To do that, Mayer and a team led by famed Titantic explorer Robert Ballard will be using a new type of technology to provide three-dimensional imagery of the caves, a kind of acoustic camera. The device uses existing multibeam sonar technology—which helped oceanographers scan the seafloor for the past 30 years—with improved resolution, computer processing speeds, and visualization software in one off-the-shelf package.

“This device can now give you a picture-like view made with sound,” says Mayer, director of the Center for Coastal and Ocean Mapping at the University of New Hampshire. “The idea is to look for places that look like a beach and a cliff but are underwater. If there are sea caves there, that’s where these people would inhabit.”

The researchers have made several previous trips to these formations, but on this trip they will examine them in greater detail with the new acoustic camera mounted on a new drone surface ship. Once they find the caves, they will send down a remote-operated vehicle called Hercules that has a high-definition video camera and robotic arms to grab samples.

The mission is just one of many recently in which ocean scientists have deployed new seafloor mapping technology and advanced autonomous vehicles to uncover startling new information about the ocean bottom. There are discoveries like the underwater sea caves, deepwater coral formations off the East Coast, and new species of marine life clustered around hydrothermal vents spewing out methane and other chemicals from the Earth’s crust. The new mapping techniques are also revealing hazards like seafloor faults, volcanoes, or unstable underwater slopes that could generate deadly tsunamis near coastal cities.

That’s what H. Gary Green and colleagues from the Canadian Geologic Service found during recent mapping of the Salish Sea, an inland waterway between the US mainland and Vancouver Island, British Columbia. They detected two active fault zones—one of them newly discovered—that could trigger rockfalls and slumps of sediment that might lead to tsunamis that could be directed toward the San Juan Islands and Bellingham, Washington.

“You don’t want to scare the public, but it’s something that should be incorporated into any analysis for hazards,” says Greene, a marine geologist at the Moss Marine Laboratories in Moss Landing, California. Greene and colleagues explored the Salish Sea with multibeam sonar sensors attached to the bottom of the research ship and seismic sensors on a small torpedo-like instrument towed 100 feet off the seafloor. Their findings were reported in April at the annual meeting of the Seismological Society of America.

Though the surface of Mars is some 34 million miles away, scientists know more about that planet’s surface than the bottom of Earth's own oceans. Many marine scientists hope that might change in the next decade, mainly by using more robots and fewer human-staffed ships. “What you have to do is take the ship out of the equation,” says Carl Kaiser, program manager at the Woods Hole Oceanographic Institution. Running a large research vessel costs from $25,000 to $60,000 per day, and research cruises can last up to six weeks for mid-ocean expeditions.

Kaiser and members of his team are developing a shore-launched autonomous vehicle that could survey deeper waters of the US exclusive economic zone, a region that stretches 200 miles from the shoreline, at a lower cost and greater resolution than ship-based surveys. Better mapping means more information about all kinds of strange environments, such as the methane seeps that attract sea life to deep plumes of minerals. “In 2013, there was a paper that found there was one naturally occurring methane seep on the US East Coast,” Kaiser says. “Today the number is north of 800, just because we have learned how to look for them and map them.”
A commercial firm is taking autonomous ocean-mapping ships to another level. Louisiana-based L3 Technologies is designing a 100-foot, single-hulled, crewless ship, the C-Worker 30, that can cruise the ocean for two months at a time, at a speed of about seven knots. Powered by diesel engines, the C-Worker 30 will also be able to launch two helper surface ships to expand the size and resolution of the underwater map. The firm is pitching its project to the Pentagon and NOAA for ocean surveys at half the cost of a crewed ship, says Thomas Chance, vice president and general manager at L3 Technologies.

Schmidt Ocean Institute

By 2030, scientists hope to have a much more accurate seafloor map of the world’s oceans, says Eric King, operations manager for the R/V Falkor, a ship operated by the Schmidt Ocean Institute, a private, nonprofit foundation. “We still have ships going over waters that were surveyed by Captain Cook with a hand lead line,” says King. In Cook's day, back in the 1770s, surveyors would toss a long rope overboard with a lead weight on the end to mark the depth of the seafloor.

With new acoustic maps, shipping companies will also be able to avoid trouble spots, while researchers will know more about the habitats of endangered fish stocks as well as valuable minerals that lie on the seafloor.

Yet even with robotic vehicles puttering through the oceans, humans will still need to go to sea to interpret the data their instruments are collecting. King leaves in August for a four-week cruise to explore a range of seven underwater seamounts between Hawaii and the Aleutians along with 44 other scientists and crew. Imagine sending that many people to Mars.

Regards

Probably the best example of a submarine cave on the sea floor is Point Dume off the Malibu coast . This has mind-boggling implications , if actually true :-

UFOs

Massive Underwater Entrance Discovered Off The California Coast

By Administrator on March 12, 2015 0 Comments

A massive underwater entrance has been discovered off the Malibu, CA coast at Point Dume which appears to be the Holy Grail of UFO/USO researchers that have been looking for it over the last 40 years. The plateau structure is 1.35 miles x 2.45 miles wide, 6.66 miles from land and the entrance between the support pillars is 2745 feet wide and 630 feet tall. It also has what looks like a total nuclear bomb proof ceiling that is 500 feet thick. The discovery was made by Maxwell, Dale Romero and Jimmy Church, host of FADE to BLACK on the Dark Matter Radio Network on Monday, May 12th 2014 and announced on Facebook, Twitter and Church’s radio program the following day.

The underwater base has been a mystery for many years with hundreds of UFO/USO sightings…many with photographs…but the entrance of the base has remained elusive…until now. The entrance can support nuclear sized submarines and massive UFO/USO activity and allow access to different military installations that are inside the US such as the China Lake Naval Base that is in the middle of the Mojave desert and the Naval Undersea Warfare Center in Hawthorne, NV between Las Vegas and Reno.

In the photographs you can see its relation to the coastline, Los Angeles and its natural surroundings which to not match up with the structure itself…which is massive in scale. The support pillars to the entrance are over 600 feet tall. Malibu, California, is known the world over for its scenic beauty and as the playground of the rich and famous. Few people know that it is also the land of UFOs.

In the late 1950s, as my neighbor and some of his friends were watching the sun setting on the Pacific Ocean, they witnessed three bright UFOs fly across the water at great speed then hover for a few minutes over the Santa Monica Mountains before flying off out of sight. My family moved in around 1962. We had a perfect view of Zuma Beach in our front yard with the mountains for our backyard, and the star-filled sky above us at night.

During the 1960s, people were frequently seeing UFOs flying around Malibu, but a lot of people were taking hallucinogenic substances in those days too. However, by the early 1970s, whole families were going down to the beach at Point Dume at night to watch the multicolored UFOs that would sink under the water at times.

SPECIAL THANKS TO MARK D. KOVAR, DALE ROMERO AND WWW.JIMMYCHURCHRADIO.COM

NOTE: The above images are from Google earth.

UPDATE 05/22/2014:

The depth from the surface of the water to the top of the structure is is 450 meters or 1476 feet and to the bottom of the entrance is 700 meters or 2296 feet.

Massive Underwater Entrance Discovered Off The California Coast

Malibu, CA, USA

A massive underwater entrance has been discovered off the Malibu,…

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Will need to look into this more, but is this the cavernous area opening that has been discussed that leads to the Navy's Nevada submarine base?

yes @Soretna , this is the same undersea tunnel that travels beneath "hollow" California , all the way to the China lake Naval base in the midst of the Mojave desert . At least one nuclear submarine that entered this underwater tunnel to investigate further , vanished without a trace...

There are accounts of people who accidentally stumbled into these underground cavern networks , that extend far inland from the California coast , but could hear the sound of sea waves and even whale songs !

Regards

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If I could give you more than one :heart: I'd give you 100 for this tidbit.

Thanks Soretna . I am really happy to know that this helped you connect the dots with some of the earlier topics we've discussed on this forum ...! :))

Regards