Geology news

Ice Cores

It seems the Vostok ice core extracted from the Antarctic ice sheet goes back around 700,000 years - and even this is a calculation based on a number of variabilities. It came to an end near the rock basement. I can remember reading something similar about a Greenland ice core - so what is actually going on. The Antarctic ice sheet is thought to be immeasurably older - by millions of years. It is thought old ice is squeezed laterally away towards the sea - to melt.

Eocene - tropical jungles thriving in what are now temperate zones

At is a report on a paper in the journal Science (June, 2011) that focuses on the Antarctic Circumpolar Current as a cause of the assumed global cooling 38 million years ago that led to the icing over of the southern continent. Up to this point, it seems, tropical jungle thrived in what is now the US Midwest, and Antarctica was temperate - with large numbers of marsupials. Was it still joined to Australia?

Giant fjords beneath Antarctica

Thiss story can be seen at and is based on a paper in Nature just out. It is also featured, with comments, at which indicates the manner of the research, radar mapping that is able to penetrate thick ice to look at what lies underneath. What they have been looking at is a subglacial basin buried under eastern Antarctica amd this basin, larger than Texas (and therefore larger than Yorkshire) is cut by fjords.

The biosphere ... beginnings

At 'Young Graphite in Old Rocks challenges the Earliest signs of Life' ... (the same story can be found at May 24th) and it seems that carbon found within ancient rocks has played a leading role in the development of a time-line for the emergence of biological life on earth. The rocks have been dated millions and even billions of years in the past - but now it has been found graphite (a carbon) dates somewhat younger, even very much younger, in what are some of the oldest rocks on earth in NE Canada.


A little geological history of the Bering Straits or Land Bridge is available at ( ). Whenever sea levels in the region dropped by 50 metres below the present position the land surfaced. The dates when this happened have been difficult to establish precisely simply because at the moment the region is submerged. In general terms it is thought Beringia was exposed between 60,000 to 25,000 years ago. During the Late Glacial Maximum, 25,000 to 18,000 years ago, it is thought Beringia was cut off both in the east and in the west.

Kerguelen, and drumlins

The idea of the geoid readjusting itself as a result of changes in the axis of rotation may not be acceptable to academic geology but it might explain a story in New Scientist 20th February 1999. An ancient land in the Southern Ocean is a geological fact of life. The Kerguelen Plateau, situated between Australia and the Antarctic, has on at least three occasions been dry land. Marine geologists discovered this piece of continental shelf system was formerly above sea level as sediments were found containing plant spores, seeds, pollen, fragments of wood and charcoal.

Can the Earth's crust move up and down?

This sounds like the sort of thing advocated by Steve Mitchell in the pages of SIS but the story is at and derives from a paper that claims the crust can move up and down like a yo-yo. However, it is nothing like the sort of thing suggested by Steve Mitchell as they are referring to plate boundaries - although the idea might possibly be extended to whole sections of plate, assuming plates are not neccessarily huge affairs.

Chesil Beach

At ... the Jurassic Coast was featured in BBC TVs Countrywise April 5th 2011 - and Chesil Beach was pictured and discussed. I had a quick look on the Net by search engine and came up with the above site. I can remember reading some years ago a tourist booklet that said the pebble and shingle beach was raised up in a storm.

The Grand Canyon ... again

Sparked by the same article as my post on March 31st, EM Smith at asks an intriguing question. The aforesaid article says the Colorado River began cutting out the Grand Canyon 17 million years ago - other geologists have suggested 3 or 6 million years. It is 277 miles long, up to 18 miles wide and up to a mile deep - but where did all the material go that got washed away?

Grand Canyon

At is an article 'How Old is the Grand Canyon?' which describes some of the conventional thinking on how long it would take a river to cut through so many layers of rock - and millions of years are involved. However, a whole mountain range has apparently disappeared - over the course of the same period of time. The disappearance is equally as mysterious as the formation of the canyon - a great slash cut out of the crust of the earth. It is also clear that science does not really know how it was formed - but ideas abound.