Author: Neville

Australia: Nullarbor Region Once Full of Fast-Flowing Rivers

Jan. 24, 2013 — University of Adelaide geologists have shed new light on the origin of Australia’s largest delta, the Ceduna Delta, and the river systems which drained the continent millions of years before the Murray-Darling system came into existence.

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It has long been thought that a massive river system, almost 2000km long, extended from Queensland’s eastern margin and entered the sea near Ceduna, depositing enormous quantities of sediment from across the continent.

In contrast, this research has revealed that between 85 and 70 million years ago the river system depositing sediment into the delta was restricted to a series of smaller, fast-flowing rivers in the area around Ceduna. This area was being uplifted as Australia and Antarctica began to break apart, forming a series of hills which were then eroded, producing a more subdued landscape that today encompasses the Nullarbor Plain.

The University of Adelaide researchers are the first to analyse the ages of mineral grains contained in sediments from the only well drilled to date into the centre of the delta in the Great Australian Bight — revealing the nature and original sources of the sediment.

“By analysing this sediment, we’ve been able to reconstruct the landscape and major river drainage systems of the Australian continent about 80 million years ago,” said project leader Dr Simon Holford. “It also gives us a better understanding of the hydrocarbon potential — the possibility of economic oil and gas production — from the region.

“To understand the hydrocarbon potential, we need to know the origin and nature of the reservoir rocks.”

The 700km-wide Ceduna Delta, off the West Coast of South Australia, is about the same size as the Niger Delta in Western Africa, containing about 0.5 million cubic kilometres of sedimentary rock including sandstones and shales.

Many deltas contain large hydrocarbon reserves, and last year BP announced it would invest up to $1.4 billion exploring the Ceduna Delta for oil and gas.

Analysing the sediment, Dr Holford, PhD candidate Justin MacDonald, fellow researchers and Melbourne-based Geotrack International Pty Ltd, dated almost 1000 grains of the mineral zircon from the well’s core samples.

“By looking at the distribution of the ages of the minerals, we were able to identify different ‘age populations’ of zircon and produce a model of a river system which transported these minerals and deposited them on the margin of the continent,” Dr Holford said.

“Our results showed that most of the sediment was derived much closer to the Great Australian Bight than has been previously thought. It gives us a much better handle on the geology and geomorphology of Australia 85-70 million years ago.”

The research has been published in the Journal of the Geological Society.

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Scientific Method / Science & Exploration

New lab could unlock vast potential of seabed methane ice

Will look into burning methane clathrates in situ on the ocean floor.

by James Holloway- Jan 26 2013, 5:00am -1100

Energy
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Enlarge / This sample of methane hydrate, which resembles ice, was retrieved by a German research vessel of the coast of Oregon.

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The University of California, Irvine has been granted $1 million to develop a unique laboratory for the research of clean energy obtained from methane hydrates, an as-yet untapped source of methane gas that exists in huge quantities in some ocean-floor environments.

Methane hydrates are clathrate compounds, where the methane molecules are trapped in a lattice of water ice—hence their alternate names, methane clathrate and methane ice. They occur where methane and water are present at favorable combinations of low temperatures and high pressure. These conditions restrict clathrates to undersea locations at polar latitudes and along continental shelves, where they are distributed within the sedimentary bed.

Such environments are plentiful, of course, and so it’s unsurprising that methane hydrate is thought to be abundant on planet Earth. However, as our understanding of methane hydrate formation has grown, our best guess as to the extent of the reserves has become smaller. Currently, the most conservative estimate is that there are between 500 and 2,500 gigatonnes of carbon in submarine gas hydrate deposits, the majority of which are in the form of methane.

Even at the low end, however, this is more than double the Earth’s 230 gigatonnes of natural gas from other sources. According to the Department of Energy, methane hydrates are Earth’s largest untapped fossil fuel resource. But quantity isn’t everything; it’s the size of the deposits that may one day prove commercially viable to tap that are key. This category of methane hydrates may prove to be a small proportion of the total.

Extracting methane hydrate poses certain logistical headaches, including the prevention of methane gas escape. Though shorter-lived in the atmosphere, as a greenhouse gas, methane is many times as effective as carbon dioxide (and typically ends up being oxidized to CO2 anyway). When it’s used as fuel, carbon dioxide is the primary output.

The researchers at UC Irvine, led by Derek Dunn-Rankin and Peter Taborek, want to see if we could sidestep both issues. They plan on examining whether it might be possible to use the methane and sequester the resulting carbon dioxide, all at its undersea source. “There are, of course, tremendous challenges and uncertainty regarding the in situ utilization of methane hydrates, but the ultra high pressure environment of the deep ocean offers some new ways to think about clean power production,” Dunn-Rankin told Ars.

To that end, the new laboratory will contain a combustion reactor vessel and a multiphase emission evolution vessel that will allow the combustion of methane from methane hydrate in simulated deep-sea conditions. “The point of the multiphase emission evolution vessel is to see how the presence of other combustion emission gases affects the CO2 capture and stability,” Dunn-Rankin explained. “It is to look for the kinetics of hydrates and mechanisms that might enhance their stability.” The methane hydrate used will itself be made in the lab.

So is there a plan to trap the carbon dioxide in a similar icy prison?

“It is not necessarily a new hydrate form,” Dunn-Rankin told Ars. “The real issue is that if you put CO2 hydrate into surroundings that have no CO2 dissolved into them, the thermodynamics would force the CO2 to gradually try to equilibrate the surroundings—which means the hydrate would dissolve. This is shown to be the case in most laboratory tests and theory. The thing is, the methane hydrates should do the same thing and yet they are stable on very long timescales. The understanding of why this might occur, the kinetics of the processes, and the effects of small amounts of natural surfactants and other species is unknown.”

The goal so far as methane hydrate is concerned, Dunn-Rankin explained, is to see if it makes any sense to use methane hydrate at the source. However, it’s thought that the lab could also see use for broader energy-related research into fuel cells, obtaining hydrogen from methane, and water purification.

Given the focus of the research, we shouldn’t expect that this new facility will handle all the unanswered questions surrounding the potential for methane hydrate exploitation. The role of methane hydrate in the stability of the ocean floor is not fully understood, and its extraction, by drilling or other means, may contribute to landslides on sloping sea floor. But the research does at least hint at the possibility of a more sophisticated approach to fossil fuel extraction and use.

Asked if he saw an inevitability to the use of methane hydrate as a source of energy, Dunn-Rankin’s response is nuanced. “For me, the use of methane hydrate as a source of energy in the future depends more on what alternative sources of energy are available,” he said. “The advances in the extraction of natural gas from shale seem to me also likely to dampen enthusiasm for more expensive and potentially riskier energy source utilization. This said, our efforts to understand hydrate dissolution and formation will always have value for the sequestration side of the problem and will allow rational considerations of methane hydrate utilization as well (we hope).”

States fear discrimination law mess

NATASHA BITA
News Limited Network
January 26, 201312:00AM

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Attorney General Nicola Roxon’s department insists the states will not be hamstrung by federal ant-discrimination laws. Source: The Daily Telegraph

A BROAD range of commonsense state rules and regulations are threatened by changes to federal anti-discrimination laws, state governments have warned.

The conservative states of NSW, Victoria and Queensland are fighting for blanket exemptions from the Gillard Government’s draft legislation, which will outlaw discrimination on 17 grounds ranging from age to sexual orientation, medical history and nationality.

They claim the new laws will stop them setting age limits for driver’s licences, or insisting that public servants be Australian citizens or permanent residents.

Judges could no longer be forced into retirement and public transport fares could not be discounted for children or seniors, they have told a Senate inquiry into the proposed new laws.

The draft Human Rights and Anti-Discrimination Bill combines and updates five sets of federal discrimination laws covering race, sex, age and disability.

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The NSW Government claims the federal laws could “invalidate” state laws that “legitimately discriminate” on the grounds of gender identity, nationality and citizenship.

It cites the ban on mentally ill people owning firearms, as one that could be challenged.

The office of Victorian Attorney-General Robert Clark provided News Ltd with a list of state government regulations that could be challenged under federal law, ranging from police arrests to guardianship orders and licence restrictions for the elderly.

Queensland Attorney-General Jarrod Bleijie attacked the federal “nanny-state” laws, which he said could override state legislation on such matters as age.

South Australian Attorney-General John Rau said he wanted “appropriate consultation” before the Federal Government finalises the bill.

“It is important that all states and territories are brought along,” he said. “Confrontation on this issue would be unhelpful.”

Federal Attorney-General Nicola Roxon is on leave, but her department yesterday insisted that the Government “has no intention of changing the way state anti-discrimination laws work”.

“The draft bill explicitly contains provisions that seek to allow state laws to continue,” spokesman David Curry said.

A general exception for “justifiable conduct” would let state governments defend claims of discrimination where their laws or programs differentiate between people for “legitimate policy reasons”.

States that desired greater certainty could apply for an “explicit exemption” from the operation of the bill.

The state governments, however, want an automatic exemption so they do not have to seek federal approval.

Evidence questions Obeid’s pecuniary interest statements

Date January 26, 2013 44 reading now

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Kate McClymont, Linton Besser

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Sam Achie leaving the ICAC. Photo: Tamara Dean

FOR years before he left NSW Parliament in mid-2011, the Labor powerbroker Eddie Obeid entered ”not applicable” in the section of his pecuniary interest declaration asking whether he had received income from a trust.

But the accuracy of those declarations is being queried following sensational revelations in a corruption inquiry this week about the millions of dollars which have flowed through six Obeid family trusts, including proceeds to the Obeid family as proceeds from an allegedly corrupt government tender.

The riches which abound in the family’s coffers have also raised questions whether the Obeids were meeting their tax liabilities.

In November 2011, Independent Commission Against Corruption officers raided the Obeids’ Birkenhead Point headquarters as part of their investigations into whether the family made millions of dollars from the allegedly corrupt granting of coal exploration licences by then minister Ian Macdonald in 2008-09.

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Among the documents seized was a trust account summary which showed that at the date of the ICAC raid, $18.38 million had flowed through the Obeid Family Trust No 1 to family members.

Giving evidence at the corruption hearing on Wednesday, Mr Obeid’s son-in-law, Sam Achie, the financial controller of Obeid Corporation, agreed that the $18 million was given to Mr Obeid, his wife and nine children as loans rather than distributions because no tax is payable on loans.

Mark Leibler, senior partner at Arnold Bloch Leibler, told Fairfax Media: ”There is nothing strange about trusts lending millions of dollars to beneficiaries.”

Referring to the $18 million received by Obeid family members, Mr Leibler said: ”Well someone must have paid tax on that money if it was accumulated by the trust. If no tax has been paid then what you’re talking about is straight out fraud or evasion.”

Mr Leibler said that if the income was accumulated by the trust, the trust paid tax at the top marginal rate of tax. More often, the income was distributed to individuals or to companies who were beneficiaries. ”Each of those beneficiaries will be taxed at its own appropriate rate of tax,” he said.

The Obeids’ trusts’ documents, which their legal team tried unsuccessfully to suppress, revealed Mr Obeid had credit card bills and other expenses paid by the family trust. In 2010 he received a $220,000 loan from the family trust to buy a holiday unit in Port Macquarie and only days after Labor lost the election in March 2011, the trust deposited $50,000 into Mr Obeid’s Commonwealth Bank account.

These payments raise questions about Mr Obeid’s pecuniary interests declarations to Parliament. In 2002 the Parliament’s privileges and ethics committee cleared Mr Obeid of any wilful wrongdoing over his 154 errors in his pecuniary interest forms.

However, the head of the ethics committee, independent MP Helen Sham-Ho, was furious that Labor had gutted her draft report.

A snapshot of the vast and secret business empire Mr Obeid and his five sons have created were revealed at ICAC this week.

Then there are the 50-odd ”non-current assets” to which the Obeid Family Trust No. 1 has issued loans worth almost $9 million. Some of these loans have been made to Obeid-associated entities including The Stables, a condominium at Perisher; Milland, which owns a vast estate at Port Macquarie which the Obeids are hoping to develop; and El-Telegraph newspaper.

Read more: http://www.smh.com.au/nsw/evidence-questions-obeids-pecuniary-interest-statements-20130125-2dc3k.html#ixzz2J28lGaem

Greenland May Contribute Less Than Antarctica to Sea Level Rise

The great ice sheet in the north may be more resistant to warming than the great ice sheets in the south

By Christa Marshall and ClimateWire

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Greenland’s ice sheet covers 660,235 square miles. It is the second-largest ice body in the world, after the Antarctic Ice Sheet. Image: Flickr/Nick Russill

Portions of the Greenland ice sheet melted a “moderate” amount thousands of years ago during an extremely warm period, raising new questions about its likely behavior in the future amid rising temperatures, according to a new study from a team of international scientists.

The conclusions about the Eemian interglacial period, 130,000 to 115,000 years ago, enlighten an ongoing debate over a deceptively simple question: To what degree will Greenland add to rising seas in a warming world, and to what degree will Antarctica?

The new study, published yesterday in Nature, suggests that Antarctica may have played a larger role in the past in adding to rising sea levels than Greenland, and therefore may follow a similar pattern in the future.

“The clues for sea level rise are pointing to the south, to Antarctica,” said James White, director of the Institute of Arctic and Alpine Research at the University of Colorado, Boulder, and one of hundreds of scientists from 14 countries contributing to the new research as part of the North Greenland Eemian Ice Drilling (NEEM) project. The National Science Foundation funded a portion of the research.

The findings are significant because Antarctica “is a more dynamic ice sheet than Greenland,” with a base well below sea level, said White. It has the potential to become more unstable over the long term as it loses ice, he said. Greenland, by contrast, is land based, providing it with a long-term “stabilizing factor” in regards to ice loss, he said.

The team of scientists found that the thickness of the Northwest Greenland Ice Sheet in the Eemian declined about 25 percent, or roughly 400 meters, over a 6,000-year period. The change in ice volume left the sheet near the NEEM research site about 130 meters below its current surface elevation.

While the decline was not insignificant, the warming at the time did not lead to the complete disappearance of the ice, as some models would suggest could happen with Greenland, said Dorthe Dahl-Jensen, a professor at the University of Copenhagen, and leader of the NEEM project. “There was a limited response in Greenland,” she explained. “The reduction in elevation was pretty moderate.”

An earlier melting had limits
This was so, she said, even though the team found that the Eemian period was warmer than previously thought, peaking at the NEEM site at roughly 8 degrees Celsius above the mean of the past millennium. At the time, the Earth was closer to the sun in the summer, allowing more solar energy to reach the surface.

The “moderate” reaction of Greenland meant that its melting ice sheet contributed less than half — or 2 meters or less — to rising sea levels in the Eemian period, she said. At the time, seas were likely 4 to 8 meters (13 to 26 feet) higher than now, according to Dahl-Jensen.

The world’s glaciers and thermal expansion of the ocean would have contributed a fraction of that rise in sea level, she said, meaning that Antarctica would have made up the rest.

Part of the reason for the “limited” Greenland response is that the warming in the Eemian lasted a short period of time in geologic terms, even though it was thousands of years, she said. “We think that saved Greenland,” she added.

Additionally, west Antarctica differs from Greenland in that it is essentially “sitting in a bowl,” meaning that its connection to warm water could speed up its melting dramatically over a long time frame, explained White.

By drilling an 8,333-foot-deep ice core, the researchers were able to obtain a snapshot of Greenland’s past by extracting very old ice and testing its chemistry and air composition. “It’s just like a tree ring in many ways,” said Dahl-Jensen.

A debate continues
Ian Joughin, a glaciologist at the University of Washington who did not participate in the research, said the study is a “nice detailed piece of work” but said it would not end the Antarctica-Greenland debate about rising sea levels in the future. He noted that the NEEM project reported a very broad range of numbers with regard to ice loss.

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