Discussion Topic |
|
This thread has been locked |
dipper
climber
|
|
|
Topic Author's Original Post - Dec 31, 2009 - 10:15pm PT
|
I am diggin all the rock talk.
I used to climb with geology students and they would enlighten me as to what I was jamming and and lay-backing off of.
So have at it with this image.
What is going on here?
|
|
Shack
Big Wall climber
Reno NV
|
|
|
Dec 31, 2009 - 11:10pm PT
|
Obviously horizontal stratification of post metasedimentary...
oh, never mind, I have no idea.
Bryan?
|
|
The Mr. Ben
Social climber
Boston
|
|
|
Dec 31, 2009 - 11:27pm PT
|
Could be a calcite deposit. If so, lenticular deposits such as this often occur in marine depositional environments, if that rock is limestone. If not, it could be secondary (i.e., water leaks through cracks in the rocks and precipitates out dissolved calcium). My hunch is #1.
|
|
Anastasia
Mountain climber
hanging from a crimp and crying for my mama.
|
|
|
Dec 31, 2009 - 11:33pm PT
|
I'm guessing...
I think that is an iron deposit on top getting all rusted and quartzite in the middle.
Am I right or did I fail gloriously?
:)AFS
|
|
dipper
climber
|
|
|
Topic Author's Reply - Dec 31, 2009 - 11:54pm PT
|
More data for the armchair rock-hounds
|
|
taorock
Trad climber
Okanogan, WA
|
|
|
Dec 31, 2009 - 11:56pm PT
|
lenticularite in laminated intercoursite?
|
|
Ihateplastic
Trad climber
Lake Oswego, Oregon
|
|
uh..huh, huh... you said intercoursite!
|
|
taorock
Trad climber
Okanogan, WA
|
|
I did - whoops. Old geo joke - another fcuking rock.
Must really be quartz in metasediments.
|
|
dipper
climber
|
|
|
Topic Author's Reply - Jan 1, 2010 - 02:01am PT
|
Some context for those interested
|
|
Mungeclimber
Trad climber
sorry, just posting out loud.
|
|
I have no idea what it is.
The real question is how does it boulder?
|
|
Curt
Boulder climber
Gilbert, AZ
|
|
Looks like petrified wood.
Curt
|
|
LuckyPink
climber
the last bivy
|
|
haha.. just as I thought
"choss pile"
|
|
dipper
climber
|
|
|
Topic Author's Reply - Jan 1, 2010 - 02:14am PT
|
In general, it is as stable as cheap styrofoam. The stuff in the first 2 shots is pretty stable though.
|
|
dipper
climber
|
|
|
Topic Author's Reply - Jan 1, 2010 - 02:44am PT
|
Even more context here
|
|
cintune
climber
the Moon and Antarctica
|
|
taorock got it, at least from the looks of it: massive "bull" quartz in lenses and irregular layers, originally deposited deep down in some kind of silt that meta'd to schist.
At least that's what it looks like.
Happy New Year, rockhounds.
|
|
Mighty Hiker
climber
Vancouver, B.C.
|
|
I think I can see the face of Sir Francis Drake in that formation...
Point Reyes has some interesting geology.
|
|
Jaybro
Social climber
Wolf City, Wyoming
|
|
The steinmen trinity?
|
|
Minerals
Social climber
The Deli
|
|
I deleted my bad joke…
Quartzite or quartz vein? There IS granite nearby…
Depositional lens or tectonic lens?
That ain’t Franciscan… And it’s moving!
Geology of Point Reyes:
http://www.sfsu.edu/~geog/bholzman/ptreyes/introgeo.htm
More geo quizzes, please!!! :)
(Edit: Damn link......)
|
|
|
SuperTopo on the Web
|
Let us know!