Eideard

Scientists say they can now explain the existence of what are perhaps Earth’s most extraordinary mountains.

The Gamburtsevs are the size of the European Alps and yet they are totally buried beneath the Antarctic ice. Their discovery in the 1950s was a major surprise. Most people had assumed the rock bed deep within the continent would be flat and featureless.

Survey data now suggests the range first formed over a billion years ago, researchers tell the journal Nature.

The Gamburtsevs are important because they are thought to be the location where the ice sheet we know today initiated its march across Antarctica. Unravelling the mountains’ history will therefore inform climate studies, helping scientists to understand not just past changes on Earth but possible future scenarios as well…

This multinational effort in 2008/2009 flew aircraft back and forth across the east of the White Continent, mapping the shape of the hidden mountain system using ice-penetrating radar. Other instruments recorded the local gravitational and magnetic fields, while seismometers were employed to probe the deep Earth.

The AGAP team believes all this data can now be meshed into a credible narrative for the Gamburtsevs’ creation and persistence through geological time…

“This research really solves the mystery of how you can have young-looking mountains in the middle of an old continent,” said US principal investigator Dr Robin Bell from the Lamont-Doherty Earth Observatory of Columbia University.

“In this case, the original Gamburtsevs probably completely eroded away only to come back, phoenix-like. They’ve had two lives,” she told BBC News…

The search also goes on for a suitable place in the range to drill for ancient ice.

By examining bubbles of air trapped in compacted snow, it is possible for researchers to glean details about past environmental conditions, including temperature and the concentration of gases in the atmosphere such as carbon dioxide.

Somewhere in the Gamburtsev region there ought to be a location where ices can be retrieved that are more than a million years old. This would be at least 200,000 years older than the most ancient Antarctic ice cores currently in the possession of scientists.

RTFA. Please. Another interesting addition to paleo-climatology and geology.

Thanks, Ursarodinia

Christchurch was so badly damaged in last month’s deadly earthquake that parts of New Zealand’s second largest city will have to be abandoned, Prime Minister John Key has said.

Key confirmed 10,000 homes faced demolition after the 6.3-magnitude tremor which is believed to have claimed more than 200 lives, warning that rebuilding would not be possible in some areas.

“We simply don’t know,” he told Radio New Zealand when asked which parts of the city would be deserted. “We know there’s been substantial liquefaction damage.

“It’s a statement of fact that there will be some properties that can’t be rebuilt… the question is whether it (rebuilding) is possible for certain parts of the city, certain streets or houses.”

Key said geotechnical engineers were working urgently to clarify the areas worst affected by liquefaction, caused when the quake’s shaking loosened the bonds between soil particles, turning the ground into a quagmire.

Community worker Tom McBrearty said the prime minister’s comments had increased anxiety among residents still reeling from the February 22 quake. “They interpreted… it as being that the riverside communities would not be allowed to be rebuilt, which is at this stage is incorrect. We don’t know, we’re still waiting for final analysis.”

Key said the government would provide financial assistance to those who were forced to move and was in talks with developers about releasing new subdivisions to cope with the demand for housing in the stricken city.

Christchurch mayor Bob Parker said speculation on the fate of entire suburbs was “alarmist” and urged residents to wait until geotechnical reports were complete.

Sad, sad tale. Although this earthquake technically was an aftershock of last year’s quake, it blasted along a new fault and being closer to the surface and in a populous area – just did an enormous amount of damage. More than anyone had foreseen.

Northern hemisphere gullies on west-facing crater slope

Sand Dunes and Ripples in Proctor Crater

Stunning photographs from that space above the Red Planet – and more.

Thousands of years of data recorded in ice

Researchers here are hopeful that the new core they drilled through an ice field on the Antarctic Peninsula will contain ice dating back into the last ice age. If so, that record should give new insight into past global climate changes.

The expedition in early winter to the Bruce Plateau, an ice field straddling a narrow ridge on the northernmost tongue of the southernmost continent, yielded a core that was 445.6 meters long, the longest yet recovered from that region of Antarctica. And while remarkably successful, the field work tested the researchers’ resilience more than most of their previous expeditions.

“It was the field season from hell,” explained Ellen Mosley-Thompson, professor of geography at Ohio State University and leader of the project. “Everything that could go wrong did, and almost everything that could break did.”

Bad weather delayed their transport to the remote drill site and snowstorms were a recurrent problem, preventing support flights in to the team. Twice, their drills became stuck deep in the ice, a drill motor broke and all three of the drill gearboxes failed, causing them to cannibalize those devices to construct a new one.

RTFA. It would make a fine documentary of the dedication and inventive spirit required of researchers working in the extremes our planet offers. The questions asked are as important as the ingenuity needed to get the samples.

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