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BP lays out riskier move to cut flow of oil

June 3, 2010 By vani Leave a Comment

(Reuters) – BP Plc started sawing extraneous pipes on Tuesday at the seabed site of its latest attempt to corral oil leaking from a ruptured well in the Gulf of Mexico.

U.S. | Green Business | Hot Stocks | Gulf Oil Spill

Moving past its failed “top kill” attempt to plug the leak, BP focused on containment rather than stopping the flow.

“We’re not talking about capping the well anymore. We’re talking about containing the well,” Coast Guard Admiral Thad Allen said at a news conference on Tuesday.

BP is counting on a pair of relief wells being drilled to intercept and plug the leak far beneath the seabed.

But the relief wells, each begun in May, will not be finished until early to mid-August — forcing the company to keep seeking a stopgap.

This week BP aims to place a containment cap with a grommet seal at the bottom on top of a lower marine riser package, or LMRP, that sits atop a failed blowout preventer at the seabed.

If the cap and seal work as hoped, leaking oil and gas will be channeled through a pipe that connects the cap to a drillship a mile above the seafloor.

In addition, BP is planning to back up the containment cap operation by using seabed equipment installed for the failed top kill to pull oil and gas from the well and channel it to a different vessel at the water’s surface.

BP expects that system to be ready by mid-June.

The company also is planning a containment system that can be interrupted if a hurricane blows through the Gulf. The 2010 Atlantic hurricane season began on Tuesday, and forecasters expect it to be active.

That would involve a riser that hangs 300 feet below the water’s surface, and can connect to a hose attached to the containment cap.

If a storm approaches, the hose can be disconnected so the drillship can move out of the way, BP spokesman Jon Pack said.

The company has consistently said it expects up to a fifth of the leaking oil to escape the cap and seal.

SAW AND SHEAR

Pack said that a diamond saw held by one of several underwater robots at the seabed on Tuesday was removing pipes next to a larger, broken pipe — called a riser — from which up to 19,000 barrels (800,000 gallons/3 million liters) of oil are leaking into the Gulf daily for the sixth consecutive week.

At times, the sawing could be seen on BP’s live seabed wecbam feed.

The riser bent and broke as Transocean’s Deepwater Horizon drilling rig exploded and sank in April, killing 11 workers.

Once the smaller pipes are gone, the robots will use huge shears to slice off the riser.

Then the saw will shave jagged bits to create an even opening for the cap.

Pack said oil and gas would “very definitely” spew from the opening during the operation. U.S. scientists said the move could temporarily increase the flow by 20 percent.

White House adviser Carol Browner called the possibility that the flow will temporarily increase “deeply, deeply troubling.”

BP said the cap is expected to be deployed later this week.

The cap is similar in theory to a much larger containment dome that BP tried to place over the end of the broken riser in early May. Cold seawater filled the dome and mixed with natural gas at high pressure, forming a type of ice that blocked oil from flowing upward.

Pack said the smaller containment cap is designed to keep seawater out and avoid that problem.

Analysts are skeptical of the cap plan.

Given previous failures, “this new prospect does not give us any real confidence that it will succeed,” analysts from British firm Arbuthnot Research said in a note to clients.

(Additional reporting by Anna Driver and Tom Bergin)

Filed Under: International News Tagged With: Admiral Thad Allen, Atlantic Hurricane Season, blowout, bp, Bp Plc, coast guard, Containment System, drillship, Forecasters, Gulf Of Mexico, gulf oil, Hot Stocks, Lmrp, news conference, oil and gas, Oil Spill, Relief Wells, reuters, seafloor, stopgap

Scientists to map Chile earthquake site to capture fresh data

March 20, 2010 By vani Leave a Comment

Washington, March 20 (ANI): A team of scientists are all set to undertake an expedition to explore the rupture site of the 8.8-magnitude Chilean earthquake, which is one of largest quakes in recorded history.

The scientists are funded by the National Science Foundation (NSF) and affiliated with the Scripps Institution of Oceanography (SIO) at the University of California at San Diego.

The scientists hope to capitalize on a unique scientific opportunity to capture fresh data from the event.

They will study changes in the seafloor that resulted from movements along faults and submarine landslides.

The “rapid response” expedition, called the Survey of Earthquake And Rupture Offshore Chile, will take place aboard the research vessel Melville.

The Melville was conducting research off Chile when the earthquake struck.

“This rapid response cruise is a rare opportunity to better understand the processes that affect the generation and size of tsunamis,” said Julie Morris, NSF division director for Ocean Sciences.

“Seafloor evidence of the quake will contribute to understanding similar earthquake regions worldwide,” she added.

An important aspect of the rapid response mission involves swath multibeam sonar mapping of the seafloor to produce detailed topographic maps.

“Data from mapping the earthquake rupture zone will be made public soon after the research cruise ends,” Morris said.

The new data will be compared with pre-quake data taken by scientists at Germany”s Leibniz Institute of Marine Sciences (IFM-GEOMAR).

Several years ago, IFM-GEOMAR researchers conducted a detailed multibeam mapping survey off Chile.

Their data will be valuable for comparisons with the new survey to expose changes from the earthquake rupture, according to researchers.

“We’d like to know if the genesis of the resulting tsunami was caused by direct uplift of the seabed along a fault, or by slumping from shaking of sediment-covered slopes,” said Dave Chadwell, an SIO geophysicist and chief scientist of the expedition.

“We will look for disturbances in the seafloor, including changes in reflectivity and possibly shape, by comparing previous data with the new (rapid response) data,” he added.

Accoridng to Bruce Appelgate, associate director for Ship Operations and Marine Technical Support at SIO, “The earthquake was a tragedy for the people of Chile, but we hope this opportunity enables important new discoveries that can help us plan for future events.” (ANI)

Filed Under: International News Tagged With: Chile Earthquake, Cruise Ends, earthquake regions, Earthquake Rupture, Institution Of Oceanography, Julie Morris, Leibniz Institute, national science foundation, Nsf Division, Quake Data, Research Cruise, research vessel, Response Cruise, Rupture Zone, Scripps Institution Of Oceanography, seafloor, sonar mapping, Submarine Landslides, topographic maps, university of california at san diego

Natural petroleum seeps release equivalent of 8 – 80 Exxon Valdez oil spills

May 14, 2009 By admin Leave a Comment

Washington, May 14 (ANI): A new study has shown that the amount of oil residue in seafloor sediments that result from natural petroleum seeps off Santa Barbara, California, is the equivalent of approximately 8-80 Exxon Valdez oil spills.

Researchers at Woods Hole Oceanographic Institution (WHOI) and the University of California, Santa Barbara (UCSB), did the study.

It shows the oil content of sediments is highest closest to the seeps and tails off with distance, creating an oil fallout shadow.

It estimates the amount of oil in the sediments down current from the seeps to be the equivalent of approximately 8-80 Exxon Valdez oil spills.

“Farwell developed and mapped out our plan for collecting sediment samples from the ocean floor,” said WHOI marine chemist Chris Reddy, referring to lead author Chris Farwell, at the time an undergraduate working with UCSB’s Dave Valentine.

“After conducting the analysis of the samples, we were able to make some spectacular findings,” he added.

There is an oil spill everyday at Coal Oil Point (COP), the natural seeps off Santa Barbara, California, where 20-25 tons of oil have leaked from the seafloor each day for the last several hundred thousand years.

Based on their previous research, Valentine and Reddy surmised that the oil was sinking “because this oil is heavy to begin with.”

“It’s a good bet that it ends up in the sediments because it’s not ending up on land. It’s not dissolving in ocean water, so it’s almost certain that it is ending up in the sediments,” said Valentine.

To conduct their sampling, the team used the research vessel Atlantis, the 274-foot ship that serves as the support vessel for the Alvin submersible.

The research team sampled 16 locations in a 90 km2 (35 square mile) grid starting 4 km west of the active seeps.

Sample stations were arranged in five longitudinal transects with three water depths (40, 60, and 80 m) for each transect, with one additional comparison sample obtained from within the seep field.

“The instrument reveals distinct biomarkers or chemical fossils – like bones for an archeologist – present in the oil. These fossils were a perfect match for the oil from the reservoir, the oil collected leaking into the ocean bottom, oil on the sea surface, and oil back in the sediment,” said Reddy.

“We could say with confidence that the oil we found in the sediments was genetically connected to the oil reservoir and not from an accidental spill or runoff from land,” he added. (ANI)

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Robo submarine all set to dive deep into Pacific Ocean

May 7, 2009 By admin Leave a Comment

London, May 7 (ANI): A robotic submarine is undergoing final preparations to dive to the deepest-known part of the oceans.

According to a report by BBC News, if successful, Nereus, the robotic submarine, will be the first autonomous vehicle to visit the 11,000m (36,089 ft) Challenger Deep in the Pacific Ocean.

Only two other vehicles have ever visited the spot before, both of them human operated.

The 5 million dollars submarine will make the attempt in late May or early June after a series of increasingly deep dives.

“Instead of jumping directly into the deep end of the swimming pool with the vehicle, we’ll probably dip our toe in first,” said Andy Bowen of the Woods Hole Oceanographic Institution (WHOI) and one of the designers of Nereus.

“We’ll work at 1,000m, 4,000m, 8,000m and then take a deep breath and see if we can get to 11,000m,” he added.

Ian Rouse, head of the deep platforms group at the National Oceanography Centre, Southampton, described the project as a “great technical challenge”.

“Below 6,500m deep (21,325ft), there are vehicles that can do a better job than Nereus due to its compromises in design,” he told BBC News. “However, from 6,500m to 11,000m, Nereus has the field pretty much to itself,” he added.

Other teams, notably the British, French, Russian and Japanese will be watching the mission “with interest”.

“The Nereus team is very experienced in designing and building other underwater vehicles, so I have no doubt they will succeed,” said Rouse.

The tests will take place on a research cruise between the 23 May and 6 June.

The Challenger Deep is the deepest-known part of the ocean, located in the Marianas Trench near the island of Guam in the west Pacific.

It is the deepest abyss on Earth at 11,000m-deep, more than 2km (1.2 miles) deeper than Mount Everest is high. At that depth, pressures reach 1,100 times the pressure at the surface.

Nereus aims to give researchers access to 100 percent of the seafloor. In its intelligent, autonomous mode, Nereus can map large areas of the ocean floor.

“The autonomous vehicle, as the name sounds, has autonomy from the human operators onboard the ship,” explained Bowen.

In this configuration, Nereus is able to fly pre-programmed missions, mapping vast swathes of the seafloor.

“It has sufficient onboard intelligence and batteries to find areas of particular interest through the use of chemical sensors, sonar and digital photography,” said Bowen. (ANI)

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Antarctica’s ice cover was much larger 10,000 years ago than it is today

May 6, 2009 By admin Leave a Comment

Washington, May 6 (ANI): New Antarctic seabed sonar images have revealed that the extent of ice covering the continent of Antarctica at the end of the last ice age around 10,000 years ago was much larger than it is today, which could help scientists to predict future sea-level rise.

Using sonar technology from onboard ships, scientists from British Antarctic Survey (BAS) and the German Alfred Wegener Institute (AWI) captured the most extensive, continuous set of images of the seafloor around the Amundsen Sea embayment ever taken.

This region is a major drain point of the West Antarctic Ice Sheet (WAIS) and considered by some scientists to be the most likely site for the initiation of major ice sheet collapse.

The sonar images reveal an ‘imprint’ of the Antarctic ice sheet as it was at the end of the last ice age around 10 thousand years ago.

The extent of ice covering the continent was much larger than it is today.

The seabed troughs and channels that are now exposed provide new clues about the speed and flow of the ice sheet.

They indicate that the controlling mechanisms that move ice towards the coast and into the sea are more complex than previously thought.

According to lead author Rob Larter from British Antarctic Survey, “One of the greatest uncertainties for predicting future sea-level rise is Antarctica’s likely contribution. It is very important for scientists and our society to understand fully how polar ice flows into the sea.”

“Our research tells us more about how the ice sheet responded to warming at the end of the last ice age, and how processes at the ice sheet bed controlled its flow. This is a big step toward understanding of how the ice sheets are likely to respond to future warming,” he said. (ANI)

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Seven new species of bamboo coral discovered in Hawaii’s deep waters

March 8, 2009 By admin Leave a Comment

Washington, March 8 (ANI): Scientists have identified seven new species of bamboo coral in the deep waters of the Papahanaumokuakea Marine National Monument, in Hawaii, US, among which six may represent an entirely new genera.

A genus is a major category in the classification of organisms, ranking above a species and below a family. Scientists expect to identify more new species as analysis of samples continues.

“These discoveries are important, because deep-sea corals support diverse seafloor ecosystems and also because these corals may be among the first marine organisms to be affected by ocean acidification,” said Richard Spinrad, NOAA’s assistant administrator for Oceanic and Atmospheric Research.

“Deep-sea bamboo corals also produce growth rings much as trees do, and can provide a much-needed view of how deep ocean conditions change through time,” he added.

Ocean acidification is a change in ocean chemistry due to excess carbon dioxide.

Researchers have seen adverse changes in marine life with calcium-carbonate shells, such as corals, because of acidified ocean water.

According to Rob Dunbar, a Stanford University scientist,”We found live, 4,000-year-old corals in the Monument – meaning 4,000 years worth of information about what has been going on in the deep ocean interior.”

“Studying these corals can help us understand how they survive for such long periods of time, as well as how they may respond to climate change in the future,” he said.

Among the other findings were a five-foot tall yellow bamboo coral tree that had never been described before, new beds of living deepwater coral and sponges, and a giant sponge scientists dubbed the “cauldron sponge,” approximately three feet tall and three feet across.

Analysis is not yet complete on the cauldron sponge, but scientists expect it will turn out to be a new species.

Scientists collected two other sponges which have not yet been analyzed, but may represent new species or genera as well.

This orange bamboo coral is another new species and new genus found in the Papahanaumokuakea Marine National Monument. It is between four and five feet tall, and was found 5,745 feet below the surface. (ANI)

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“Psychedelica” fish has a wild swirl of tan and peach zebra stripes

February 25, 2009 By admin Leave a Comment

Washington, Feb 25 (ANI): Scientists have dubbed a newly discovered fish as “Psychedelica”, as it has a wild swirl of tan and peach zebra stripes and behaves in ways contrary to its brethren.

The odd looking fish, which has rare, forward-facing eyes like humans and a secretive nature, was first spotted a little more than a year ago in the busy harbor of Ambon Island, Indonesia.

According to University of Washington’s (UW) Ted Pietsch, Psychedelica is an apt name, given the absurd way the fish swim, some with so little control that they look intoxicated.

Members of Histiophryne psychedelica, or H. psychedelica, don’t so much swim as hop.

Each time they strike the seafloor, they use their fins to push off and they expel water from tiny gill openings on their sides to jettison themselves forward.

With tails curled tightly to one side, which surely limits their ability to steer, they look like inflated rubber balls bouncing hither and thither.

While other frogfish and similar species are known to jettison themselves up off the bottom before they begin swimming, none have been observed hopping.

It’s just one of the behaviors of H. psychedelica never observed in any other fish, according to Pietsch, UW professor of aquatic and fishery sciences and curator of fishes at the UW Burke Museum of Natural History and Culture.

Adults of H. psychedelica are fist-sized with gelatinous bodies covered with thick folds of skin that protect them from sharp-edged corals as they haunt tiny nooks and crannies of the harbor reef.

Fins on either side of their bodies have, as with other frogfish, evolved to be leg-like, and members of H. psychedelica actually prefer crawling to swimming.

The species has a flattened face with eyes directed forward.

While other anglerfish change their coloring depending on the environment, the new species appears to maintain its wild striping no matter the surroundings.

The coloring led co-author David Hall, a wildlife photographer, to speculate that the fish is mimicking corals.NA work has revealed that H. psychedelica joins two other species in the genus Histiophryne, though the other two are very drably colored in comparison. (ANI)

Filed Under: Science News Tagged With: ability, Ambon Island, anglerfish, ANI, bottom, burke, change, co-author, comparison, control, culture, curator, David Hall, environment, face, Feb, Fins, fish, fishery, frogfish, Gill, harbor, Histiophryne, history, hop, Indonesia, jettison, matter, museum, name, natural, Nature, none, peach, photographer, professor, Psychedelica, reef, rubber, seafloor, side, skin, swimming, swirl, tan, Ted Pietsch, thither, time, University, Washington, water, way, wildlife, work, year, zebra

French battleship sunk in 1917 found on Mediterranean Sea floor

February 20, 2009 By admin Leave a Comment

London, Feb 20 (ANI): In a survey for a gas pipeline between Algeria and Italy, a company has discovered a French battleship sunk in 1917, in remarkable condition on the floor of the Mediterranean Sea.

According to a report by BBC News, the ship, known as The Danton, with many of its gun turrets still intact, is sitting upright in over 1,000m of water.

It was found by the Fugro geosciences company during a survey for a gas pipeline between Algeria and Italy.

The Danton, which sank with 296 sailors still onboard, lies 35km southwest of the island of Sardinia.

The ship, named after the French revolutionary Georges Danton, was 19,000-tonne, and 150 m-long; and was carrying over 1,000 men when it was attacked by Germany’s U-64 submarine at 1317 on 18 March, 1917.

Naval historians record that the Danton’s Captain Delage stood on the bridge with his officers and made no attempt to leave the ship as it went down.

The ship dug out the sediment as it hit the seafloor. Despite tumbling through the water, many guns stayed in place.

“Its condition is extraordinary,” said Rob Hawkins, project director with Fugro GeoConsulting Limited.

“After it was hit by the torpedoes, the Danton clearly turned turtle and rotated several times. You can see where it dropped some infrastructure on the way down and then impacted on the seabed,” according to Hawkins.

“You can see where it slid along the seabed before coming to a rest,” he told BBC News.

A comparison with the original plans for the battleship – in particular, the position of its 240mm guns – confirms the wreck’s identity.

The final resting place is a few kilometers from where people have traditionally thought the ship met its end.

The wreck is just off the point where the southern pipeline meets Sardina.

“The French Admiralty did argue with us for a while that it should have been several nautical miles away, but we reminded them that modern GPS methods are more accurate than the sextants they used in those days,” said Hawkins.

Analysis of the Danton’s debris field suggests the battleship landed at the bed from the northwest.

As a consequence, a decision was taken to offset the 66cm-diameter pipeline by 300m to the southeast of the wreck location, thus avoiding any obvious structural items that had fallen clear of the vessel during its descent and forward of any sediment kicked up in the bed impact. (ANI)

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Deep-water drilling identifying strains and slips in major earthquake fault

February 16, 2009 By admin Leave a Comment

Washington, Feb 16 (ANI): An international project is using cutting-edge deep-water drilling technology to identify strains and slips in the Nankai Trough, a major earthquake fault off the coast of Japan.

Known as the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE), it is the first geologic study of the underwater subduction zone faults that give rise to the massive earthquakes known to seismologists as mega-thrust earthquakes.

“The fundamental goal is to sample and monitor this major earthquake-generating zone in order to understand the basic mechanics of faulting, the basic physics and friction,” said Harold Tobin, University of Wisconsin-Madison geologist and co-chief scientist of the project.

Subduction zone faults extend miles below the seafloor and the active earthquake-producing regions – the seismogenic zones – are buried deep in the Earth’s crust.

The NanTroSEIZE project, an international collaboration overseen by the Integrated Ocean Drilling Program, is using cutting-edge deep-water drilling technology to reach these fault zones for the first time.

“If we want to understand the physics of how the faults really work, we have to go to those faults in the ocean,” Tobin explained.

“Scientific drilling is the main way we know anything at all about the geology of the two-thirds of the Earth that is submerged,” he added.

The decade-long project, to be completed in four stages, will use boreholes, rock samples, and long-term in situ monitoring of a fault in the Nankai Trough, an earthquake zone off the coast of Japan with a history of powerful temblors, to understand the basic fault properties that lead to earthquakes and tsunamis.

The project is currently is its second year.

During the first stage of the project, the team found evidence of extensive rock deformation and a highly concentrated slip zone even in shallow regions that do not generate earthquakes.

One rock core from a shallow part of the fault contains a narrow band of finely ground “rock flour” revealing a fault zone between the upper and lower plates that is only about two millimeters thick – roughly the thickness of a quarter.

Above deeper portions of the fault, the team discovered layers of displaced rock and evidence of prolonged seismic activity that suggest a region known as the megasplay fault is likely responsible for the largest tsunami-generating plate slips.

“A fundamental goal was to understand how the faults at depth connect up toward the Earth’s surface, and we feel that we’ve discovered the fault zone that’s the main culprit,” Tobin said.

The next stage of drilling will commence this May, with plans to drill additional boreholes into the plate above deep regions of the fault zone. (ANI)

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Seamounts may serve as refuges for deep-sea animals

February 12, 2009 By admin Leave a Comment

Washington, Feb 12 (ANI): New findings indicate that seamounts may serve as refuges for deep-sea animals that struggle to survive elsewhere.

Over the last two decades, marine biologists have discovered lush forests of deep-sea corals and sponges growing on seamounts (underwater mountains) offshore of the California coast.

It has generally been assumed that many of these animals live only on seamounts, and are found nowhere else.

However, two new research papers show that most seamount animals can also be found in other deep-sea areas.

Seamounts, however, do support particularly large, dense clusters of these animals. These findings may help coastal managers protect seamounts from damage by human activities.

Tens of thousands of seamounts dot the world’s ocean basins. Although some shallower seamounts have been used as fishing grounds, few seamounts have been studied in detail.

Davidson Seamount, about 120 kilometers (75 miles) offshore of the Big Sur coast, is an exception. Since 2000, researchers have spent over 200 hours exploring its slopes and peaks using the remotely operated vehicle (ROV) Tiburon.

Following each expedition to Davidson Seamount, marine biologists at MBARI studied high-resolution video taken by the ROV and identified every animal they could see.

Over 60,000 of these observations were entered in MBARI’s video annotation and reference system (VARS).

Craig McClain and Lonny Lundsten, the lead authors of the two recent papers, used the VARS database to find out which animals were unique to Davidson Seamount and which had been seen elsewhere.

Altogether, 168 different species of animals were observed on Davidson Seamount. McClain’s search of the VARS database showed that 88 percent of these animals had also been seen or reported in other deep seafloor areas, such as the walls of Monterey Canyon.

Three quarters of the species on Davidson were not even unique to the California coast, and had been seen in seafloor areas over 1000 kilometers (620 miles) away, including the Hawaiian Islands, the Sea of Japan, and Antarctica.

Only about seven percent of the species at Davidson Seamount had never been seen anywhere else. Of these 12 apparently “endemic” species, most were new to science.
lthough few animals are “endemic” to Davidson Seamount, the research demonstrated that this seamount does support distinctive groups of animals, which are dominated by extensive “forests” of large, “old-growth” corals and sponges.

According to Craig McClain, one of the lead authors, “The large groves of corals and sponges are unique to seamounts. The crests of seamounts are particularly good because they provide flat rocky surfaces that don’t accumulate much sediment. This is partly due to the fact that seamounts are so far offshore.” (ANI)

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