What mineral, or minerals, are we looking at in this Scanning Electron Microscope image?
Bonus points for people who can tell us anything about where you might find this stuff, and how it forms. If you’re struggling, click here for a picture of a possibly more familiar form of the same thing.
Update: Click through for the answer
Callan wonders if Google Maps (or, indeed, Google Earth) could be used to create a spatial directory of interesting geological localities:
One thing that I found frustrating and limiting in my first few years of teaching was that there was no good single source to go to find out about relevant outcrops. It took time and experience to find out where the cool rocks were. Is it a good idea to put this information online in a publicly-accessible format so beginning instructors and interested students/amateurs can visit interesting outcrops?
I’ve picked up a truly excellent book out here which describes the general geology, and highlights particularly interesting outcrops, along the major highway routes here in South Africa – a wonderful resource for anyone interested in what’s going on in all those road-cuts. I’ve often thought that an on-line version which tries to do a similar thing – a kind of geo-spatial wiki – would be a wonderful resource: you can check to see if your journey takes you close to anything interesting, or look up information on something that you’ve just driven past, or even conduct virtual fieldtrips on other continents.
Obviously there are potential issues with geovandalism (and the exact locations of certain rare fossil sites should probably never be disclosed in this manner), but is this something that we should consider doing (or starting, anyway)? Ron surely has some ideas about this, if he hasn’t set something up already. Let me know your thoughts.
It’s been interesting to watch the ScienceDebate 2008 campaign snowball over the past couple of months, but things are about to get even more interesting: a time (April 18th) and a place (the Franklin Insitute in Philadelphia) have been decided upon, and invitations have been sent out to the four remaining principal contenders.
It’s a tribute to the hard work put in by the people behind this campaign (including our very own Chris and Sheril) that things have got to this juncture, but now comes the hard part – getting the candidates on board. This is effectively down to you, the (American) reader: we all know that every campaign move the presidential hopefuls make is calculated purely on its vote-winning potential, so they need to feel that agreeing to participate in a debate on science and technology issues is going to win them some favour. That will only happen if you let them know. Here’s what Sheril wants you to do:
- Contact the campaigns, and tell them to attend ScienceDebate2008! A list of contact information for the campaigns can be found here (see right margin).
- Write letters to the editor of your local newspapers, raising further awareness about this initiative. Some handy letter writing tips can be found here.
- Tell a friend about ScienceDebate2008 (handy link here). We need to spread the word as much as possible at this critical time. We’re at 13,000 supporters right now; we want to get to 15,000 supporters by the end of the week and 20,000 supporters by the end of the month. We need your help to make that happen.
Remember, this debate is not intended to be a pop quiz on science. It’s more a chance to examine the different candidate’s approaches to scientific issues which concern us all – and check that they’re actually informed and rational. From a broader perspective, remember that the tools of science are largely employed to identify, and then remove, the errors and biases which distort our view of the world, something which is hardly irrelevent in a political environment as polarised as the modern day US. Science is just a technical form of critical thinking, which values pragmatism; a willingness to go with what works, rather than what you’d like to work; and above all, a readiness to revise your opinions in the face of contradictory data. You know, all those things that have been noticeably missing from American governance for the last 8 years – if not longer.
Believe me, the rest of the world will be watching this with interest.
Did you know that any steel forged since 1945 is mildly radioactive? This is the result of isotopes that we’ve introduced into the atmosphere, after we decided to play with our new nuclear bombs by detonating as many of them as we could get away with in ‘tests’ (“Yes, that one destroyed everything for miles around too! Still plenty of Pacific atolls to vaporise, though. Tee-hee!”). As a result, for some applications, such as making sensitive measurements of radioactivity (for example, shielding whole body counters for measuring radioactive exposure), old steel is much better than new.
One of the best sources of this venerable and increasingly rare material is, bizarrely enough, sunken warships. A particularly good source is the sunken remnants of the German Imperial Fleet, which was interned at Scapa Flow in the Orkney Isles following the German surrender at the end of the WWI. Most of the ships were eventually scuttled by their German crews to keep them out of enemy hands, and although salavage and decay have taken their toll, there are still several large chunks of ‘pre-atomic’ steel within easy reach beneath the shallow waters of Scapa*.
The coolest thing of all, though, is that some of this steel is used in satellites and space probes. That’s right, the German Navy has made it into orbit – bits of it, anyway.
This interesting little titbit was brought to my attention courtesy of one of my Christmas presents: An Utterly Impartial History of Britain by John O’Farrell, which had me chuckling from start to finish as well as being extremely interesting. To give you an idea of the tone, the author ends the standard apologia for any errors left in the text being his own with:
My only defence is that these mistakes are fairly minor compared to the decision of the Scottish army to invade England during the Black Death.
Definitely my sort of book.
*One of my favorite whiskeys whiskys is also produced nearby.
(image source)
I’m not feeling at my best today (I’ve been laid low over the last couple of days with a mild fever), but I thought that that a brief discussion of Friday’s puzzle was in order. As most of you correctly guessed, the photo was taken in a river channel, and many of the boulders in the photo show signs of being imbricated, which is a fabric generated by the effects of strong currents on flattened or disc-shaped clasts, with large flat surfaces. When such clasts are pointing into a current, then the water will strongly push on the flat face and flip them over so that they point downstream. After this, the current just pushes them down into the stream bed; so over time you tend to get all the flattened clasts pointing stacked on top of each other and pointing downstream.
For lot's more videos on soil moisture topics, see Drs Selker and Or's text-book support videos https://www.youtube.com/channel/UCoMb5YOZuaGtn8pZyQMSLuQ/playlists
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Nice plan for content warnings on Mastodon and the Fediverse. Now you need a Mastodon/Fediverse button on this blog.