A brief thumbing through 'Fossils of the World' easily identified these albeit slightly ropey specimens. They are in fact a fossil called Gryphaea arcuata, a mollusc from the Jurassic, i.e. 180 - 135 Ma. According to the natural history museum web site, this is a fairly common fossil but is particularly common to Suffolk, Gloucestershire and the Scunthorpe area, where the Lower Jurassic rocks were mined for their iron ore. Quite why so many of these fossils are lying in amongst other random pebbles and chunks of granite I've no idea. Maybe the dressing supplied to the company to decorate the borders is just a mix of waste rocks of about 2 -3 cm just thrown together.
Anyway, this little chap consists of two pieces, being what I believe is called a 'bi-valve' - a curved left valve and a flat, lid-like right valve. I have only managed to find one example of the latter, seen at front left of the photo. The curved part of this little creature sat in the soft sediment with the lid above the surface. They are commonly called 'Devils Toenails' apparently, presumably because of their resemblance (with a bit of imagination) to toenails? Well, sort of . . .
It seems amazing to me that even in these fairly poor quality specimens, there are distinct growth bands to be seen, which is remarkable for something up to 180 million years old and have most recently been churned up in sacks! But this is what is amazing. Looking at something that stems from something that lived millions of years ago, is pretty mind blowing. Well, mind blowing to me at least. I'm not sure the rest of my family quite understand the fascination - yet!
So, there you go - my first fossil find! A bit of a cheat really, as they were rather handed to me on a plate! What I need next , is a genuine 'first', out in the field extracting a nice trilobite or ammonite from its rocky matrix. Proper palaeontology?
All in good time eh?
Before I go, I had a message posted up (see here) in response to my June post on the 'Geology of Charnwood'. The postee highlighted an innocent error on my part which I've corrected and highlighted my lack of acknowledgement of the source of my information. While I recognise that paraphrasing other peoples work and passing it off as ones own constitutes plagiarism in academic work, perhaps one should bear in mind what 'Holey Schist' actually is - a humble blog! A serious piece of academic work it ain't! I have and always will acknowledge my sources of text and photos, when I deem it sensible, but please remember folks, these are just the casual ramblings of a wannabee geologist - no more, no less!
Cheers for now!
Alyn.
No comments:
Post a Comment
Any thoughts or comments on anything you have read?
Drop me a line and I will respond shortly!