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IAU’s “Plutons” making geologists mad.
Posted on Tuesday, August 22, 2006 @ 7:34 am by Dave Schumaker
The International Astronomical Union has proposed a definition for the word planet. Included within this new definition is a subunit of planets called “plutons”, based on similar characteristics of the planet (as of this writing) Pluto.
Unfortunately, the word pluton is already used frequently in the world of geology to describe bodies of magma that crystallized within the Earth’s crust and this is making some geologists rather angry. The astronomer who proposed to use the word pluton didn’t believe it was all that common due to the fact that the spellchecker in Microsoft Word flagged it as a wrong word! Hah.
The main argument by geologists against using the word is that the fields of planetology and good, old fashioned Earth geology are fairly similar that it might cause confusion. The astronomer who proposed the definition doesn’t believe that will be the case, but is willing to come up with a new name.
Bacterial Alchemy!
Posted on Wednesday, August 9, 2006 @ 1:25 pm by Dave Schumaker
Scientists in Australia have discovered that certain types of bacteria play a very important role in the formation of secondary gold grains (and helping to intitiate the precipitation of gold from solution).
Dr. Frank Reith analyzed bacteria found among the gold grains and in solutions from the Hit or Miss Mine in Queensland, Australia and discovered 30 unique species that were significantly different from bacteria found in the surrounding soil. When Dr. Reith placed one species of bacteria, Ralstonia metallidurans, in a petri dish, he was able to observe the gold precipitating from solution.
As the article notes, this may have some benefits to the mineral exploration industries since current models relating to gold deposits do not account for the precipitation of gold from a solution due to biological activity. Also, see this Science Daily article from May, 2002 about how bacteria could possibly be used to find gold deposits.
In other news relating to bacteria, geology and various elements, Science Daily is reporting on a new study by the Department of Energy’s Pacific Northwest National Laboratory that shows the bacteria Shewanella oneidensis is able to chemically modify uranium by covering it in a “special goo,” making it much safer to store. Rather interesting read.
The Sliding Rocks of Racetrack Playa
Posted on Tuesday, August 8, 2006 @ 3:12 pm by Dave Schumaker
The Racetrack Playa in Death Valley is world famous among geologists for its unique “sliding rocks”. However, no one has ever seen these sliding rocks in motion, leaving many different theories as to how they ultimately move about the playa.
The San Bernardino County Sun, a newspaper in Southern California, ran a small article in today’s paper about this unique place and the possible theories of the rock’s movement, such as high winds combined with a thin layer of ice during the winter.
For those who don’t know about the Racetrack Playa or have never seen it, Flickr has some wonderful pictures of it, and I also found an interesting blog post about a visit to the Racetrack. Lastly, here’s a link to the location in Google Maps.
Carbon Sequestration in Deep Sea Sediments
Posted on Monday, August 7, 2006 @ 9:26 pm by Dave Schumaker
Researchers from MIT and Harvard hypothesize that deep sea sediments can be used to store large amounts of man-made carbon dioxide. Charles Harvey, who is a co-author of the paper that will appear in this week’s issue of the Proceedings of the National Academy of Sciences, says that CO2 injected into the deep marine sediments is permanently sequestered.
High pressure and low temperature at ocean depths of 3,000 meters or greater provide ideal conditions to store the carbon, say the researchers. Here, the carbon dioxide is in a liquid form that is denser than the surrounding water and has no chance of escaping to the surface.
The researchers claim that the deep sea sediments located within the territorial waters of the United States would provide enough space to sequester the carbon for “thousands of years.”
Wired News had a good article from November, 2004 of carbon sequestration as well.
Related information: Carbon dioxide sink via Wikipedia.
Sumatra Earthquake Caused Gravity Change
Posted on Sunday, August 6, 2006 @ 10:35 am by Dave Schumaker
According to a new article published in the latest issue of the journal of Science from Ohio State University, NASA’s GRACE satellites have detected a gravitational change in the Indian Ocean after the 2004 Indian Ocean earthquake.
Unfortunately, the article from OSU is rather light on details. It simply explains, “The earthquake changed the gravity in two ways that we were able to detect. First, the quake triggered the massive uplift of the sea floor, changing the geometry of the region, and second, the density of the rock beneath the sea floor was changed after the slippage. An increase or decrease in density produces a detectable gravity change…”
The abstract is available for free via the Journal of Science’s website, however you will need a subscription to access the full article.
Research from OSU and the GRACE satellites have previously been covered on Geology News in an article dealing with the Permian Extinction.
