Rio Tinto is letting go 14,000 people in an attempt to reduce debt and react to rapidly deteriorating market conditions. This is:
-60% of the population of Alice Springs.
-20% more than the entire attendance of next week's AGU meeting.
-One person per month since the reign of Charlemagne.
A few weeks back, shortly before my job with Uramet terminated, the chief geo and I were doing some work out at the Geoscience Australia core library. I took the opportunity to grab the portable XRF analyzer, and check the old, peeling paint on out railings for lead. The good news is that they were not Pb paint- the Pb content was measured in ppm, not percent.
Not content to turn the machine off with my peace of mind intact, I decided to move on to the windows. When we bought the house, we replaces all the old, leaky, single-pane aluminum windows with swish double-glazed uPVC windows. I’d head something about metals such as lead being used in some plastics, so I figured I’d take a look. A spectra is shown below:
The dominant peak is the chlorine peak. Since PVC stands for polyvinyl chloride, this is not surprising. The Ti is probably related to the white pigment. And there is also substantial calcium and lead. I don’t have a standard to compare this to, but the instrument’s built-in, assume-it’s-a-crustal-rock firmware estimates 1-2% Pb.
So from now on, LLLL is not allowed to chew on the windows. Aside from that, though, I don’t really know what to make of this. I know fuck all about plastic stabilization, much less how it is regulated. So I don’t have the environmental knowledge required to calibrate my level of parental worry. If anyone better educated than I wants to pitch in, that would be great.
I'm unemployed!
Also, a bit tipsy.
And yesterday, I got an official job rejection letter. It was from a government agency, and they can only hire permanent residents if no qualified Australians apply. So that was pretty much expected. Still. Anyway.
I had a good chat wth everyone else who got sacked today- the board stopped operations, so everyone from the managing director down to the fieldies is looking for work. Maybe if we'd driven a prius to Washington they would have bailed us out. Oh well. The chairman has a point, which is that if good results don't raise the shareprice or atract investment, there isn't much point spending the money needed to get the results. Still, it is a bit frustrating to have to walk away from half finished projects. Oh well. Welcome to the real world. I leave it to a junior geo 10 years from now to dig up our reports and ask his boss, "Why didn't the drill this one out?"
In the mean time, anyone with 5 cents in their pocket can pick up not one, but two shares of uramet stock. It floated at 20 cents.
Currently, a story about the Hadean Earth is the banner article in the science section of the New York Times. This is good. As the article explains, the Hadean- formally the time from Earth’s formation to 4 billion years ago, and informally the time for which we have no rocks- is traditionally underconstrained (no rocks, no data). But in the last few decades, rocks and individual minerals have been found, and the picture that is emerging is that the Hadean may have been more similar to the modern Earth than originally thought.
This is all well and good, and I have no argument with the science or the presentation of it. People in the know have known about evidence for a wet early Earth for years, and the New York Times is a good place to get that knowledge out into the wider human community. However, I have a complaint about the way the reporting was done, which could prove problematic with a more contentious topic.
The writer of the Times piece writes:
“The picture that’s emerging is a watery world with normal rock recycling processes,” said Stephen J. Mojzsis, a professor of geology at the University of Colorado who was not involved with the U.C.L.A. research.
Mojzsis’s name is not on the paper, and he may have been unaffiliated with this particular project. However, a quick Google scholar search will show that he and Harrison have co-authored a dozen papers over the last decade or so on early earth evolution. Several of these papers include work done on Jack Hills zircon, which is the topic of the Nature paper at the heart of the article. So presenting his opinion as that of an uninvolved, detached scientist is probably a bit of a stretch.
I don’t know how much training or education science journalists get with regards to the culture of scientific collaboration, but simple tests like reading the names on a publication list will at least give a hint as to how connected or independent various scientists are.
As an aside, Harrison and Valley did not discover Hadean zircons. That was done in the early eighties. What happened in 2001 was that both groups developed (independently) the ability to measure oxygen isotopes on single zircon grains to the precision needed to make inferences about the source magma of the zircon.
And anyone wishing to know more about the state of research into the Early earth should get to San Francisco in the next week and a half. There are several sessions at the annual fall AGU meeting.
Thus far, science has discovered planets around more than 250 stars. Most of these are too faint to see without a telescope, but a couple are quite bright, and several others can be found if you know where to look. Currently, a couple of these are high in the Southern sky. Fomalhaut, with a recently imaged planet that has been blogged everywhere, was just about directly overhead in November at sunset, and is now just a bit west. Click the image to see the stars in question.
Also visible is Epsilon Eridani, which is the closest star with a known planet. It is fairly dim, so despite being only 10 light years away, it is an inconspicuous star, the second in a line of four stretching away from Rigel up and to the north. So far, only huge gas giants have been detected. But these systems almost certainly have rocky planets or moons with outcrops waiting to be mapped.
I've mowed my face down to just the mo now, for the last gasp at Movember. I'd like to thank both of the regular readers who have donated thus far. If anyone else wants to do so, the following link should take you to the donation page:
http://tinyurl.com/6j9jge
Please give generously.
Plymouth Rock, where the Mayflower pilgrims allegedly alighted on the new world, is a large boulder of Dedham granite. Like the pilgrims, this granite has traveled.
It is a glacial erratic, meaning that it was scraped off the ground and picked up by a glacier, and it then dropped into its current position when the glacier melted during the waning years of the last ice age. The Dedham granite from which it is derived is a neoproterozoic intrusive that forms much of the crystalline basement of the Esmond-Dedham terrane.
This terrane forms the bedrock of much of eastern Massachusetts and most of Rhode Island. The 680 Ma granites intrude older clastic sediments, which contain predominantly Grenville-aged zircons. But the basement on which those sediments settled is a mystery.
The Esmond-Dedham does not just have a mysterious bedrock; it has an exotic origin as well. It is an accreted terrane. It is a sliver of the southern supercontinent of gondwana, and only arrived at its present North American position in the last gasp of the Alleghenian orogeny, the last of the three mountain-building events that formed the Appalachian mountains.
So when the pilgrims stepped onto that rock, those transported souls were disembarking onto an erratic dropstone of a microcontinent, which itself had traveled from Africa, back before the Atlantic Ocean even started to form.
Here on planet earth, even the solid ground moves around the globe. Splitting, sliding past, colliding and attaching to each other, these continental fragments travel around the globe at the whims of convection.
In is not in the nature of this planet to be static; we leave that to the dead moons and asteroids of the solar system. But for an evening, tomorrow, we can cease our wanderings, and gather together for company, cheer, chow, and thankfulness. Unlike Plymouth Rock, most of us are not born of lava, witnesses to the birth of mountains and seas, and surfers of continental glaciers. But we can all tell stories, give thanks, and enjoy this great American holiday.
Happy Thanksgiving.
