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Post by 1dave on Nov 3, 2013 13:06:26 GMT -5
I like to TRY to decipher the past history of rocks like this one from the Wah Wah Mountains of western Beaver County Utah where there has been lots of volcanic activity. What came first?
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Deleted
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Post by Deleted on Nov 4, 2013 13:41:01 GMT -5
dave it seems your image is overexposed, and, at least on my screen, I cannot see details.
Does it have crinoids in it?
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Post by 1dave on Nov 4, 2013 13:59:49 GMT -5
It is not as sharp as I would like. I'll have to take more close up photos of the various areas. It looks to me like it once was a void that dark red agate formed in. That was caught in an ash flow tuff that stopped with a shattering event, but the shattered agate remained within an inch or so of each other. The penetrating ash crystallized into plumes, then agate filled most of the remaining spaces.
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Post by 1dave on Nov 4, 2013 16:37:13 GMT -5
It is snowing here! I took this photo indoors with a veg oil coating. Is that better Scott? Dave
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Post by 150FromFundy on Nov 4, 2013 18:33:36 GMT -5
It looks like a brecciated jasper. What if red jasper was fractured along a fault line, then the fractured material was filled in with quartz, agate, chalcedony, etc?
Darryl.
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Post by 1dave on Nov 10, 2013 12:28:51 GMT -5
That's all? I expected more from forum members.
What force broke the original agate? A fall would have widely scattered the pieces. Crushed in place would have left them tight together.
What kept the pieces apart, yet close together?
Why was the space between the shards filled with plumes/moss instead of milk agate etc.?
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jamesp
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Post by jamesp on Nov 10, 2013 18:45:14 GMT -5
When those answers are answered please post. i do not understand it. That is an amazing stone. I collect on the Rio Grande and there are 16,738,823 combinations of silica jewels.
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Post by 1dave on Nov 12, 2013 16:08:13 GMT -5
It is usually obvious if a stone grew from the center out, like a pearl, or from the exterior to the center as in "fortification agate, or from the bottom up as in "waterline agate." Some of our understanding is clouded by "Old Scientist Tales." Here is another puzzle in Morrisonite, NOT my slabs. Note something different happened to the bottom two examples from the shattered examples on top. All examples were taken from Googling "Morrisonite Images."
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Post by Deleted on Nov 12, 2013 17:47:14 GMT -5
Some of our understanding is clouded by "Old Scientist Tales." Another member here called that something different. If memory serves he called it "tribal knowledge". I am less polite than you both. I simply call it dogma.
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Post by Deleted on Nov 12, 2013 17:51:23 GMT -5
I can't explain morrisonite with or without "bubbles". When I think about these things I always attempt to keep Occam's Razor in mind. To me breccia happens like cracked mud: Then the next agatization event happens, filling in the cracks. As agates come in many flavors, I see no reason the cracks cannot be filled in with any other type (or color) of agate. It seems to me we have even seen breccia that then got brecciated and then refilled again. Anybody?
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jamesp
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Post by jamesp on Nov 12, 2013 19:23:19 GMT -5
Never thought about that. Seems obvious. Cool theory Scott. I wonder if that is why shrinkwood is called shrinkwood(commonly in Texas).
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Deleted
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Post by Deleted on Nov 12, 2013 21:08:10 GMT -5
We got a lotta dry mud here in Cali. Here are the two images side by side. Tell, me they aren't similar. Even the minor/secondary cracks line up as similar.
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Post by Deleted on Nov 12, 2013 21:18:38 GMT -5
On further review of this image so kindly provided at my demand request I see multiple events going on. Here is my take on it. 1) burgundy jasper forms 2) burgundy jasper brecciates 3) burgundy breccia is filled in with clear/white agate (can you see it?) this is held together in some form of mud/clay/gel 4) mud/clay/gel is washed away and then agatized or simply agatized (I offer no opinion on which) probably yellow but maybe red 5) contrasting moss is grown and this solidifies the entire nugget 6) scott wants a 5" cube of this material
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Post by 1dave on Nov 13, 2013 10:12:02 GMT -5
@shotgunner Excellent! I'm still puzzled by the wide "stream" that runs through the middle - the quarter is in the middle of it. Does event 6) point to some future event like a spherical development? How did you deduce that? Man, you are good!
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Post by 1dave on Nov 13, 2013 11:15:31 GMT -5
Luckily we have the Bruno Jasper to help us understand what happened to some Morrisonite. Bruno began as spheroids that were "popped open" by water expanding up to 2,000% into steam as cooling and contracting magma reduced the surrounding pressure. As cooling continued, the openings became vacuum chambers. In other areas the spaces were produced by openings in ledge rock. in both cases, the chambers were surrounded by highly silicious clay. Blobs of that material was injected into the chambers by repeated pulses by something like Old Faithful repeatedly pressurizing the groundwater.
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Deleted
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Post by Deleted on Nov 13, 2013 13:27:24 GMT -5
@shotgunner Excellent! I'm still puzzled by the wide "stream" that runs through the middle - the quarter is in the middle of it. Does event 6) point to some future event like a spherical development? How did you deduce that? Man, you are good! No clue if I am good or not. I just broke it down into the various stuff. What had to come before other stuff and so on. Am I right? Haha! who knows?
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Post by 1dave on Nov 21, 2013 15:41:07 GMT -5
How do the plumes and moss form? I just visited my saw shop where it is cold now. Here is my bottle of Dawn! You folks from the warm wild coast could put your bottle in the frig and think thank thunk upon the phenomenon.
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