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Massive ancient undersea landslide found near Great Barrier Reef

Massive ancient undersea landslide found near Great Barrier Reef Science & Technology World Website

Scientists have discovered evidence of massive ancient undersea landslide next to Australia's Great Barrier Reef, according to media reports on Thursday.

Dr Robin Beaman of James Cook University said, This is all that remains after a massive collapse of sediment of about 32 cubic kilometres volume more than 300,000 years ago.

He said that the remains of the slip, known as the Gloria Knolls Slide, were discovered 75 kilometres off the north Queensland coast near the town of Innisfail while the scientists were working from the Marine National Facilitys blue-water research ship Southern Surveyor.

Dr Beaman said a debris field of large blocks, or knolls, and numerous smaller blocks, lies scattered over 30 kilometres from the main landslide remains, into the Queensland Trough, to a depth of 1350 metres.

We were amazed to discover this cluster of knolls while 3D multibeam mapping the deep GBR seafloor. In an area of the Queensland Trough that was supposed to be relatively flat were eight knolls, appearing like hills with some over 100 m high and 3 km long, he said.

Associate Professor Jody Webster from the University of Sydney likened the research to a detective story, first finding the knolls, then using later mapping to reveal the landslide source of the knolls.

A sediment sample from a knoll at a depth of 1170 metres identified a remarkable cold-water coral community of both living and fossil cold-water coral species, gorgonian sea whips, bamboo corals, molluscs and stalked barnacles.

The oldest fossil corals recovered off the top of the knoll was 302 thousand years, said Dr Angel Puga-Bernabu at the University of Granada and lead author on the study, which means the landslide event that caused these knolls must be older.

Modelling the potential tsunami for a sudden mass failure on this scale yields a three-dimensional tsunami wave elevation of about 27 metres. However, the wave would likely be dampened significantly by the presence of any coral reefs.

Considerably more seabed mapping and sampling is needed to fully assess the tsunami hazard to the Queensland coast posed by these types of underwater landslides, the scientists said.

The scientists said one-third of the Great Barrier Reef lies beyond the seaward edge of the shallower reefs, and the discovery of this prominent undersea landslide and its vast debris field in the deep Great Barrier Reef reveals a far more complex landscape than previously known.

This research was a collaborative effort between James Cook University, University of Sydney, University of Granada, University of Edinburgh and the Australian Nuclear Science and Technology Organisation.

Continued undersea volcanic activity may form new island

Massive ancient undersea landslide found near Great Barrier Reef Science & Technology World Website

The newest addition to Japan’s archipelago is most likely a permanent landmass, this coming from experts as they continue to study Japan’s latest volcanic island in the Pacific Ocean. As of Nov. 24, continued volcanic activity was spotted from an observation aircraft, including the eruption of lava and debris into the air, at the site off Nishinoshima Island, 1,000 kilometers south of central Tokyo in the Ogasawara island chain.

Aboard the plane was Setsuya Nakada, a professor of volcanological studies at the Earthquake Research Institute of the University of Tokyo. “The lava flow was about 100 meters long as it made its way into the sea,” Nakada said. Lava flow usually is a good bet for the permanence of an island – once lava cools, it hardens and increases the odds that the island will remain. Some newly formed volcanic islands are eroded by the ocean and tend to slip back underneath the waters. The path of the magma appeared to be stable, according to reports from the observation plane. Since it was first spotted, the volcanic island has grown to more than 20 meters in height, around the same height as nearby Nishinoshima Island, with its highest point of 25 meters.

The island was first spotted by the Japan Coast Guard on Nov. 20, and was announced by the Japan Meteorological Agency on Nov. 21. The Japanese government is actually a little bit pleased with this situation, as one can never have more than enough territory. Chief Cabinet secretary Yoshihide Suga said that “if it becomes a full-fledged island, we would be happy to have more territory.” If the island becomes permanent, it will further extend Japan’s territorial waters.

The Japan Coast Guard and Japan Meteorological Agencyannounced that a small island has risen in the far south of Tokyo after avolcanic eruption occurred under the sea sometime between Wednesday and Thursday. Scientists are not sure if the island will become permanent or if it will eventually be eroded away.

The advisories from the two government agencies say that the island is around 200 meters in diameter and is located off the coast of the uninhabited island of Nishinoshima which is part of the Ogasawarachain or Bonin Islands, just 1,000 kilometers south of Tokyo. On Wednesday, the coast guard issued an advisory on Wednesday, saying heavy black smoke was coming out of the waters in the area. Then on Thursday, footage showed smoke, ash and rocks were exploding from the crater. The last time the volcanoes in the area erupted was in the mid-70s, and most of the activity was underwater, thousands of meters deep into the Izu-Ogasawara-Marianas Trench.

Hiroshi Ito, the coast guard’s resident volcanologist said that there was a strong possibility the new island will be eroded, but it can also stay there on a permanent basis. Chief Cabinet secretary Yoshihide Suga said that this has already happened before, but the islands eventually disappeared. He added, ‘‘If it becomes a full-fledged island, we would be happy to have more territory.’ Japan, being an archipelago already has thousands of islands, which are often used to claim wide expanses of ocean that are rich in minerals and energy resources.

"Smart" undersea pipeline sends status reports to shore

Massive ancient undersea landslide found near Great Barrier Reef Science & Technology World Website

Undersea oil pipelines are typically inspected about once every five years ... but what happens if one of them gives out between those inspections? That's where the Norwegian SmartPipe project comes in. Initiated in 2006, it's aimed at developing self-monitoring pipelines that continuously transmit real-time status reports to shore.

Developed by Norwegian research group SINTEF, the prototype pipelines created so far have been equipped with sensor-packed belts spaced 24 meters (79 ft) apart along the length of the pipe. These belts monitor factors such as pipewall thickness, tension, temperature and vibration.

Additional electronics, embedded in the pipeline's insulating outer layer of polypropylene, allow data to be wirelessly relayed from the various belts to the shore – or to an offshore drilling platform.

In tests performed last fall, 200 meters (656 ft) of the pipeline was lowered into Norway's Orkanger Harbor, to see how the electronics would handle being submerged in seawater. They reportedly did well, although some sensors were destroyed in subsequent reeling tests, in which the pipeline was reeled onto drums as it would be for transport. According to SINTEF, small modifications to the sensors should remedy that problem.

The SmartPipe project is now about to move into its pilot phase, in which the pipelines will actually be put to real-world use. An American oil company, which was previously looking into developing smart pipelines of its own, has expressed an interest in the technology.



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