Ok, I'm bored so I figure I'll start a little game. Post a picture, diagram, thin section etc and highlight a feature that everyone else will try to identify. It can be a rock type, weathering feature, structural feature, landform, fossil or pretty much anything you like, but try to avoid names of specific localities unless perhaps they're known globally. First person to guess correctly gets the next go.
It can be your own picture, or one you find off the net. Remember to change the filename if its a dead giveaway.
Ok, I seem to be able to see crystals and they don't look too altered (hard to tell from a photo) so I'm going for igneous.
Overall colour is dark so probably a mafic/intermediate rock (unless it's one of those weird Na-rich magmas which I have no idea what they look like).
It appears to have great big phenocrysts so probably slow or two-stage cooling (can only see the white crystals).
No crystal alignment so even less chance of metamorphic.
It also seems quite localised, the valley sides in the top of the photo appear to be a different rock.
So, all I've got is a mafic/intermediate igneous rock with slow or two stage cooling with an apparent localised extent. There appears to be some kind of structure too it but I can't quite make out what it is.
My guess is therefore an ophiolite suite, in particular the gabbroic base. (Troodos Mountains?)
However, I've never been to Cyprus or seen an ophiolite anywhere so I'm expecting to be well off the mark! :oops:
Seems to be either a volcanic plug of some sort - picrite with the large crystals? or the eroded top of a dyke.
Reminds me a bit of the picrites at Margi in Cyprus.
The ropy texture may be a bit misleading -could be erosional rather than a flow form as no lobes are visible which suggests to me that its not a bolster type pillow lava...
Ooo wow! I was a bit iffy because you had said no to it being Pahoehoe! I suppose you were just being very specific!
Anyway...Heres my submission, I took this in a museum, I'm still nt 100% sure on it myself, but i also took pictures of the description at the side, but i will give people a chance to guess first!!!
And the little creature in the corner...Thats Jeremy, our society mascot!!!
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obvious: its a stone age seismograph
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Stylolite!
Geologists are gneiss!!
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Stylolite!
Bingo! Your turn.
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Okee dokee.
Try this landform...
Geologists are gneiss!!
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obvious: its a stone age seismograph
nice joke Theape
Could be Drumlin, Jon?
Lucky man whose destiny is to know the Earth´s secrets. Eurípides (480-405)
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Drumlin is right! All yours, Javi!
Geologists are gneiss!!
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Ok
Volcanic structure:
Lucky man whose destiny is to know the Earth´s secrets. Eurípides (480-405)
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Pillow Lava?
Ben.
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Nope,
try again Ben.
Lucky man whose destiny is to know the Earth´s secrets. Eurípides (480-405)
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Is that an example of ropey lava otherwise known as pahoehoe? Or is it some AA or blocky lava?
Cum hoc ergo propter hoc
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I thought it might be pahoehoe, but they are big ropey bits!
Geologists are gneiss!!
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nope,
Lucky man whose destiny is to know the Earth´s secrets. Eurípides (480-405)
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Pillow lava?
Mike
To me, road cuts serve more as tourist attactions.
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Ok, I seem to be able to see crystals and they don't look too altered (hard to tell from a photo) so I'm going for igneous.
Overall colour is dark so probably a mafic/intermediate rock (unless it's one of those weird Na-rich magmas which I have no idea what they look like).
It appears to have great big phenocrysts so probably slow or two-stage cooling (can only see the white crystals).
No crystal alignment so even less chance of metamorphic.
It also seems quite localised, the valley sides in the top of the photo appear to be a different rock.
So, all I've got is a mafic/intermediate igneous rock with slow or two stage cooling with an apparent localised extent. There appears to be some kind of structure too it but I can't quite make out what it is.
My guess is therefore an ophiolite suite, in particular the gabbroic base. (Troodos Mountains?)
However, I've never been to Cyprus or seen an ophiolite anywhere so I'm expecting to be well off the mark! :oops:
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Points: 448
Seems to be either a volcanic plug of some sort - picrite with the large crystals? or the eroded top of a dyke.
Reminds me a bit of the picrites at Margi in Cyprus.
The ropy texture may be a bit misleading -could be erosional rather than a flow form as no lobes are visible which suggests to me that its not a bolster type pillow lava...
www.bgs.ac.uk www.mdsg.org.uk www.le.ac.uk/geology www.geolsoc.org.uk www.ex.ac.uk/csm Did you know that the name Cyprus is derived from the greek/latin for copper? or vice versa.....
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Well, I took the pic in Tenerife, Canary Islands during a journey last year.
As you said Simon, it´s a Picrite, I think to remember...Ankaramite (more exactly).
It is a sort of volcanic structure (remember).........(if you give up I´ll say the answer).
Cheers,
Javi
Lucky man whose destiny is to know the Earth´s secrets. Eurípides (480-405)
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Im stumped! I went to Tenerife on a field trip last year, which was absolutely amazing!!
I'd have said pahoe-hoe toes!
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You got it Ekp, the answer is lava toes
Your turn
Javi
Lucky man whose destiny is to know the Earth´s secrets. Eurípides (480-405)
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Ooo wow! I was a bit iffy because you had said no to it being Pahoehoe! I suppose you were just being very specific!
Anyway...Heres my submission, I took this in a museum, I'm still nt 100% sure on it myself, but i also took pictures of the description at the side, but i will give people a chance to guess first!!!
And the little creature in the corner...Thats Jeremy, our society mascot!!!
Rank: Fluorite
Joined: 20/04/2005
Points: 316
Yeah, ekp it´s so specific.
About your pic, I would say it seems an ocelar granitoid, or something similar.Maybe Rapakivi, like those placed in Finland.....
Regards
Javi
Lucky man whose destiny is to know the Earth´s secrets. Eurípides (480-405)
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Points: 6
Yeah, ekp it´s so specific.
About your pic, I would say it seems an ocelar granitoid, or something similar.Maybe Rapakivi, like those placed in Finland.....
Regards
Javi
Whats "Ocelar"? Its not Rapakivi! But what a brilliant word that is!!
Well, at least the museum description doesnt use either of those words!!
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I mean....ocellar, ekp.
Lucky man whose destiny is to know the Earth´s secrets. Eurípides (480-405)
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Its been a few days now... perhaps a clue is needed.
Edit- This new forum confuses me. It seems to pick a new font at random every time I post!
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condrites?
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Orbicular granite?
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I think we need to move on now...So who wants to go next?
Geologists are gneiss!!
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What's the v shape?
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A burrow!? It's a big 'un if it is!
Geologists are gneiss!!
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Not a burrow!
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Stalactite that has had sediment filled in around it?