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Identity HelpBeach Rocks (Plutonic?)
26th Feb 2012 20:40 UTCP. Michael Hutchins
I collect mineralogically interesting beach rocks from a geologically-complex area around Boston (Marblehead). Some look to me like they're displaying flow banding; some, magmatic immiscibility. Some have ~micro-graphic granite~.
(the graphic texture is (almost) too small to see w/ the naked eye)
Some have almost agate-like bands w/ xls on one side, all swirling around (folded?).
And so on.
I haven't figured out even where to look for information about these / this kind of rocks.
My first question was:
What minerals would this ~magma~ have turned into if it had cooled slowly enough?
Now I just want to learn enough to be able to look at one of these rocks and read its story, tell how it formed.
(I'm not a geologist; just love geology, mineralogy, etc.)
(MIT: Pure Math, Computer Science)
I'd treasure advice on where all to look, what discipline(s) this might fit into, technical terms that would help in searches, etc.
26th Feb 2012 22:23 UTCPaul Brandes 🌟 Manager
28th Feb 2012 00:02 UTCVik Vanrusselt Expert
http://www.bostongeology.com/
Vik
28th Feb 2012 20:58 UTCP. Michael Hutchins
I was definitely remiss in not including any photos!
Here's one of each rock that I have out for this purpose. I can certainly make zooms if they'd help.
28th Feb 2012 23:47 UTCPiotr Zając
The first one looks like almandines in some kind of shist,
Third one is some variety of chalcedony, probably flint
Second... I am not quite sure. For sure it is sedimentary rock, I see a lot of calcite, I think it has grains, so maybe it is sandstone, or even limestone with grains.
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Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: April 19, 2024 05:51:49