Friday, 3 December 2010

Very cold worms

As Lucy says, the happy expression in the previous post was well justified. As it happens, that particular moment might have had more to do with suddenly being able to feel my toes again (it's a grimace with frostbite, honestly), but the principle works.

It turns out that reports of whole sponges were entirely accurate, and strange things they were too. The first sign was bubbly black markings in the mudstone that stand out much better when wet (convenient, that). We've not yet found a whole one, but I reckon the entire thing was probably a good 10 cm long... which for the earliest Ordovician (Tremadoc) is quite unusual. The black preservation is some oxidation product of pyrite (we found one or two fresh ones as well).

There were other sponges as well, including this amazing little thing, a mere centimetre or so across. The stalk is like nothing I've ever seen on a fossil before, although I'm sure there are some recent ones that are fairly similar...

Following our adventures with worms in Mid Wales the past couple of years, where the fabulous little beasties known as palaeoscolecids turn out to be rather common, we were half expecting to find more of the same. As a reward for being mad enough to go out in the aforementioned weather, the gods of fossils let us have some. Well, at least one definitive one... plus lots of others that might be, but without such obvious, enormous plates. Since the worm is 1 mm diamater, those nice obvious plates must be a good 30-40 microns across...
The object of this trip was to investigate a possible field site for our reseach over the next couple of years. I reckon it passes the test... we can't wait to get back.

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