Interesting Geology

freeztar · September 10, 2009

From your pics, it's quite obvious to anyone that you have procured a chunk from the walls of Gomorrah. The burn marks are clearly seen in the material you present. ;) :eek_big:

Turtle · September 10, 2009

From your pics, it's quite obvious to anyone that you have procured a chunk from the walls of Gomorrah. The burn marks are clearly seen in the material you present. :hihi: ;)

:rotfl: :bow: ..... :rotfl: stop! yer killin' me! :rotfl:

fear not neither heaven nor hell. :goodbad: gonna get me some while the gettin's good boy! :phones: :jab: :joker: i have been to the mountaintop and it's tephra all the way down. :singer: :)

speaking of my photos, i want to take a moment to thank my sponsor hypography and her dad tormod. :bow: it is not apparent in the photo of me in front of the rockface, but i am wearing my hypography t-shirt as seen in the photo below. my thinking is that if i am stopped or challenged for being where i be, i will expose said shirt & declare i am here, or there, under sponsorship of a bona fide science association and that tormod sent me. :D it also occured to me today, as i slipped going down the slope, fell on my ***, and slid some 3 meters before regaining my feet, that i could refer hospital staff to my sponsor for settlment of my surgery fees. :eek: :D

this tephra cobble has a veeeeerrrry interesting vug*, indicated by the arrow. more on that on the morrow.

* Vug - Wikipedia, the free encyclopedia

freeztar · September 10, 2009

I like the shirt. :phones:

eThe vug is nice as well. Watha got in there?

Turtle · September 10, 2009

I like the shirt.
eThe vug is nice as well. Watha got in there?

what the heck; it's the morrow somewhere on this rock so carpe diem. :rotfl: i love my t-shirt by the by. :singer:

now i have an opinion as to what this is in that thar vug, but i'll put up the photo for input from all y'all rock houndies and invite yer opinionations afore i gives mine. :rotfl: :rotfl: it is going to be a different matter altogether as to how it got there, which is to say was it captured from surrounding rock by the erupting material, or, did it form inside the cavity during or after the eruption??? enquiring minds want candy!! :phones: . . . . . . :goodbad:

green mountain tephra vug mineralization

Turtle · September 10, 2009

i'll get back to my little pocket of crystaline mineral growth in a bit, but this interesting geology story trumps & bumps mine hands down. it is intersting to note however that both deposits, my cinder cone & the mexican miners' crystals, are just over a half-a-million years old. if i'm correct about the contents of my vug, the minerals may have similar formation mechanisms as well. :goodbad: . . . . . .:phones:

Crystal Cave of Giants - Naica, Mexico

The Crystal Cave of Giants was accidentally discovered in 2000 by miners working in the silver and lead mine at Naica, Mexico. It lies almost 300 meters (900 feet) below the surface of the Earth and it contains the largest crystals known in the world, by far. The largest crystals are over 11 meters long (36 feet) and weigh 55 tons.

The crystals themselves are made of selenite which is crystallized gypsum, the same material used in drywall construction. Except these crystals formed over a span of about half a million years in a hot water solution, saturated with minerals. ...

freeztar · September 11, 2009

what the heck; it's the morrow somewhere on this rock so carpe diem. :eek2: i love my t-shirt by the by. :eek_big:

now i have an opinion as to what this is in that thar vug, but i'll put up the photo for input from all y'all rock houndies and invite yer opinionations afore i gives mine. :dog: :eek2: it is going to be a different matter altogether as to how it got there, which is to say was it captured from surrounding rock by the erupting material, or, did it form inside the cavity during or after the eruption??? enquiring minds want candy!! :eek_big: . . . . . . :eek_big:

green mountain tephra vug mineralization

Yttrium?

Turtle · September 11, 2009

Yttrium?

rats!!! lost a post!!! :dog: not yttrium; alienium maybe? :eek2: :eek2:

my first blush was chalcedony? >>> Chalcedony - Wikipedia, the free encyclopedia :eek_big:

this source requires my closer scrutiny & review. lots to ~~garnet~~ garner there from both the map & the desriptive text. >> http://pubs.usgs.gov/sim/2006/2924/LacamasCrk_map.pdf

they gave the age of the green mountain rock at over 1/2 million years & i was thinking about how big the cone got way back then. this type of volcano is often a one-shot wonder. :eek_big: . . . . .. :eek_big:

Turtle · September 11, 2009

here's what i lost earlier. :doh: :rant: :eek2: something new on the formation of chalcedony: >> SpringerLink - Journal Article

Abstract The structural disparities that distinguish chalcedony from macrocrystalline quartz suggest that different crystallization mechanisms are operative during the growth of these two forms of silica. Although the paragenesis of chalcedony has provoked marked disagreement among researchers, a review of previous studies supports the idea that chalcedony can precipitate from slightly saturated aqueous solutions at relatively low temperatures (<100° C). These conditions for deposition suggest a model for chalcedony crystallization that involves the assembly of short-chain linear polymers via bridging silica monomers. ...

mind you chemistry isn't my strongest suite...ok, it's a little weak....alright then! my chemistry is lame. :eek2: :dog: might need a little help from you chemists on some of these minerals from time to time. :eek_big: :bow: :eek_big: :eek_big:

Turtle · September 12, 2009

still on the mineral deposit in the vug, i also lost a comment i made about doing a "scratch test" on it. i actually meant to say a "streak test", but i did both & here's the result.

streak: none

hardness: somewhere between 5.5 & 6.5 on the mohs scale

determining streak: >> Mineral Resources: Streak

Streak is the color of a crushed mineral's powder. The color of a mineral's powder may differ from the actual color of the mineral. This property is useful for mineral identification.
...
When testing for streak, the mineral must be crushed to determine the color of its powder. The color of the powder is the color of the streak. Instead of actually crushing a mineral to determine the streak, it is much simpler and cost-effective to swipe the mineral across a streak plate. A streak plate is an unglazed piece of porcelain...

can you find my streak plate in the bench photo? :clue:

determining mineral hardness: >> Mohs Hardness Scale

There are a few handy objects that also fit in the Mohs scale. A fingernail is 2½, a penny (actually, any current U.S. coin) is just under 3, a knife blade is 5½, glass is 5½, and a good steel file is 6½. Common sandpaper uses artificial corundum and is hardness 9; garnet paper is 7½. ...

a knife blade did not scratch my sample, but a hardened file did. :cap: :clue:

so it may be chalcedony which has a white streak & hardness of 6 - 7. the game is afoot. . . . . . . . . :turtle: :hihi:

quasarwolf · September 13, 2009

any geologists in here? i would like some answers or to run some of my ideas by them

modest · September 13, 2009

Howdy, Quasarwolf,

Go to the Earth science forum, start a "New Thread", and ask away.

~modest

lemit · September 13, 2009

This really is interesting geology. It seems like there is so much boring in geology.

(I have about 20 more puns. I was writing them and got angry at myself. Sorry everybody.)

--lemit

Turtle · September 14, 2009

This really is interesting geology. It seems like there is so much boring in geology.

(I have about 20 more puns. I was writing them and got angry at myself. Sorry everybody.)

--lemit

likely too much sleep led to your indiscretion so i'll allow that it's not your fault and move on. :hyper:

i filed off some more of my smaller green mountain cobble, wrapped a small magnet in paper, passed it through the grindings, tapped off the excess, and recovered a few grains of magnetic minerals on the paper. likely magnetitie. i tried taking some photos through my loop but they sucked. :doh: maybe sandy claws will bring me a video microscope for christmas. :santa: or not. :hihi: :loser:

interesting to note that green mountain is older than either mt. st. helens @~300ka (ka=1,000 years), and mt. adams @~220ka. as the crow flies from green mountain, st. helens is ~50 miles n. and adams is ~60 miles north-east. st. helens actually lies in the path of the view to rainier that i posted as a screen shot from google in post #45, but since she blew her top you can't see her from that angle. :boy_hug: :eek:

Pre-1980 Eruptive History of Mount St. Helens, Washington | USGS Fact Sheet 2005-3045

CVO Website - Mount Adams Volcano, Washington

Thunderbird · September 16, 2009

As soon as saw the sample pic and the bluish color I thought, chalcedony , then read you had the same first impression., the hardness test should be about a six. you confirmed that. So if I know a thing are two about first blush insights into mineral identification we are probably wrong. You should be able to locate the some larger specimens that have been sorted out in the lower stream beds. Btw we have a sub-volcanic terrain just south of here. A collapsed caldera 1.5 yr billion yrs old, the ignimbrite layers contain blue chalcedony , I considered cutting some but decided it was not worth the effort.

Turtle · September 16, 2009

As soon as saw the sample pic and the bluish color I thought, chalcedony , then read you had the same first impression., the hardness test should be about a six. you confirmed that. So if I know a thing are two about first blush insights into mineral identification we are probably wrong. You should be able to locate the some larger specimens that have been sorted out in the lower stream beds. Btw we have a sub-volcanic terrain just south of here. A collapsed caldera 1.5 yr billion yrs old, the ignimbrite layers contain blue chalcedony , I considered cutting some but decided it was not worth the effort.

:rolleyes: thnx. :evil: will keep an eye out for more goodies if i get back over to the mountain, though i don't expect any sizeable gem-quality rocks. this 'chlalcedony', if that's what it is, is vesicular and full of cracks and inclusions. :phones:

Thunderbird · September 16, 2009

FYI.... for verbally challenged like myself "chalcedony" is one of those minerals I pronounced wrong until I heard it spoken correctly. its proper pronunciation is “Cal-Sidney“.