June 2006

Jokulhlaups are floods that are the result of a sudden outburst of water, ice and sediment from a glacier. These are traditionally very hard to predict and analyze, however a team at the University of Leeds has developed new models to predict what happens during and after a jokulhlaup in terms of landform changes. The article is unfortunately light on details, but it interesting nonetheless.
Their research will be tested this coming summer when they go to New Zealand in order to examine any jokulhlaups that are created when snow melts from Mount Ruapehu.

Here are two photos on Flickr that show the damage a jokulhlaup in Iceland caused in 1996 as a 10km wide swath of water swept down a valley.

I’ve recently started using my account at Flickr a lot lately and am really getting interested in all the tagging options that you can use. For those who aren’t aware of what “tags” mean in a technological sense, it’s basically a collaborative way for people to organize a lot of different content between users of particular websites.

So I upload a picture to Flickr and assign a bunch of tags (keywords that describe it), such as geology. For example, my picture of geology tools has various tags that I associated with it: geology, notes, rock hammer, rocks, and field notes. Now if someone searches any of these tags, this picture will be shown along with any other pictures with the same tag.

It allows you to easily find unique pictures of a similar subject. Here is a list of interesting geology pictures found on Flickr (though note it is mostly pictures of geologic structures and formations).

Other websites allow you to search by people’s tags as well: del.icio.us geology bookmarks, geology videos on youtube.com, and geology blogs on technorati.com.

The website Damn Interesting has reposted an article that appeared on their website back in January, titled “The Physics of Quicksand.” This piece talks about the actual physics behind real world quicksand, as opposed to the quicksand that Hollywood always shows us. It turns out, we really don’t have all that much to fear when we’re hiking through tropical jungles and such. However, there is potentially a very dangerous type of quicksand called “dry quicksand.” Fortunately, it has only been created in a laboratory environment!

How Stuff Works also has a great article on quicksand as well (and even tells you how you can get yourself out of it). It also contains interesting tidbits on the natural elements and forces that create quicksand. The last link on quicksand is a link from Wikipedia.

More information available at National Geographic’s website as well.

Researchers from Ohio State University using data from NASA’s GRACE satellites believe they have discovered a 300 mile wide crater beneath Antarctica’s ice sheet that is thought to be roughly 250 million years old, roughly the age of the Permian - Triassic “Great Dying” event.

A rift zone within Indian Ocean cuts through the center of the suspected crater (due to the impact) and researchers believe it may have influenced the formation of Australia nearly 100 million years ago when it broke off from Gondwanaland (see our recent post on why continents form).

Previous theories behind the Great Dying have been discussed on Geology News as well. See volcanoes, gas hydrate deposits and climate change.

More information: Ohio State University Press Release

Columbia Hills, Eagle Crater, Bounce Rock. Have you ever wondered how scientists in charge of the various Mars Exploration Rovers mission come up with the unique and sometimes goofy names they assign to rock outcrops and other geographical features? Popular Science tackled this question back in November, though I just now discovered the article while searching for other Mars related geology items. It’s an interesting article that talks about the International Astronomical Union’s guidelines and how NASA has also had to makeup their own guidelines as they went along.

In current Mars related news: According to the mission status report for May 30, Opportunity is currently stuck in a sand in a dune field. This comes just over a year after being stuck in a patch of sand back in April of 2005, where the rover was immobilized for five weeks while engineers figured out how to get the rover out. Here’s to hoping they get her out soon! Meanwhile, Spirit is currently parked on top of the Columbia Hills for the Martian winter, absorbing as much sunlight as possible and waiting until more optimal energy conditions are present before it moves again.

Lastly, the Mars Science Laboratory (NASA’s newest Mars lander) will launch in 2009. Scientists are currently looking for geologically interesting areas on Mars and hope to have a site selected by 2008.