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Post by 1dave on Oct 22, 2020 11:03:07 GMT -5
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Post by 1dave on Oct 22, 2020 12:04:00 GMT -5
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RWA3006
Cave Dweller 
Member since March 2009
Posts: 4,625 
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Post by RWA3006 on Oct 27, 2020 22:11:12 GMT -5
I took a new look at the area this morning and realized I was 180 degrees wrong on the impact direction. The comet was traveling 117 degrees from north, headed east southeast. 1dave this changes things quite a bit about the formation of the San Rafael Swell and the rift! I'll be interested to see what your thoughts are on the subject. |
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Post by 1dave on Oct 28, 2020 6:33:44 GMT -5
I took a new look at the area this morning and realized I was 180 degrees wrong on the impact direction. The comet was traveling 117 degrees from north, headed east southeast. 1dave this changes things quite a bit about the formation of the San Rafael Swell and the rift! I'll be interested to see what your thoughts are on the subject. The impact created the Liesegang bands in scenic sandstone, the Moqui Marbles, AND shock waves, like a huge plumbers plunger forcing water back and forth created the sandstone pipes! forum.rocktumblinghobby.com/post/1131661/thread |
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Post by 1dave on Oct 28, 2020 10:23:19 GMT -5
What is a shockwave?  A shock wave can best be described as a highly nonlinear and unharmonic acoustic soundwave that is characterized by an extremely steep change in the pressure amplitude, the so-called shock front. The parameters of a a shock wave known, include the pressure maximum, pulse rise time, half width time of the pressure wave, and a negative pressure phase of the shock wave.(Fig. 1 below). The acoustic energy of the shock wave is proportional to the product Pmax x r2 x t where Pmax is the maximum pressure of the shock wave in focus, r is the radius of the said focal area, and t is the half-width time of the shock wave.  Fig 1. Parameters of focused Shock wave. , Pmax, pressure Maximum. pressure rise time, tw, half width time. Pr, negative peak pressure. Energy is expressed in joules or millijoules where as pressure is expressed in bar or megapascal. The focal zone of a a lithotripter is, by definition, the volume within which the shock wave pressure is greater than 50% of the maximum pressure. A common property of all shock wave devices is the cigar-shaped, three dimensional form of the focal zone, with a density for intensity in this focal zone is defined as the acoustic energy divided by the area (intensity = energy/area). This is shown diagrammatically below in Fig2.  For deeper detail - iopscience.iop.org/chapter/978-0-7503-1254-7/bk978-0-7503-1254-7ch1.pdf   So rocks strike rocks, bounce back, are struck again. But speed changes as bodies of other types of rocks and even bodies of water are encountered! 1. General (later . . .) 2. Angle - What happened at Upheaval Dome as the ground liquified.   |
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Post by mohs on Oct 28, 2020 11:30:48 GMT -5
Amazing Something as simple as a wave is so complex 150 years of contemplating the double slit light wave experiment Something interfering with those photons Shadows? even going back to Heraclitus ha ya cant step into the same wave twice m  stly |
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Post by stephan on Nov 1, 2020 20:40:21 GMT -5
1dave Given that Nevada, Idaho, Utah and other places that have elevated uranium concentration also have relatively high arsenic concentrations, would it be plausible to suspect that this impact gave us a wide variety of heavy metals?
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RWA3006
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Member since March 2009
Posts: 4,625
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Post by RWA3006 on Nov 1, 2020 23:00:45 GMT -5
1dave Given that Nevada, Idaho, Utah and other places that have elevated uranium concentration also have relatively high arsenic concentrations, would it be plausible to suspect that this impact gave us a wide variety of heavy metals? After spending a life time learning about this stuff nothing would surprise me. Amaze me, yes, but not too surprised. |
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Post by 1dave on Nov 1, 2020 23:30:53 GMT -5
Yes highly possible!
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Post by 1dave on Nov 5, 2020 17:45:11 GMT -5
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,625
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Post by RWA3006 on Nov 5, 2020 20:25:22 GMT -5
1dave I really enjoyed obsessing over all those cool photos and recognizing so many places. Unfortunately? I lost myself identifying potential places to hunt coprolite and I entirely forgot what you were talking about. I'll pay better attention next time. Thanks for an awesome presentation.
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Post by grumpybill on Nov 8, 2020 9:09:26 GMT -5
I see that the map shows PA as having a uranium mine. I've lived here all my life (except for stints with the military and school) without knowing that. I've known there's a radon problem, but always assumed it was seeping up through the miles of sedimentary rock I live on. Time for some research! |
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Post by 1dave on Nov 8, 2020 9:34:29 GMT -5
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Post by grumpybill on Nov 8, 2020 9:47:34 GMT -5
Some cursory research shows that most of the uranium in PA is found in the Eastern part of the state, although there is at least one "dump" near me in Western PA left over from processing in the early 50s.
The uranium deposits were found in river gorges that cut through the sandstone and shale. None of the deposits were found to have commercial value. The ore that was mined in the early 50s was trucked away for testing and processing by the AEC. That testing/processing was never done because larger/better deposits were found in the West.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,625
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Post by RWA3006 on Nov 9, 2020 9:27:45 GMT -5
Some cursory research shows that most of the uranium in PA is found in the Eastern part of the state, although there is at least one "dump" near me in Western PA left over from processing in the early 50s. The uranium deposits were found in river gorges that cut through the sandstone and shale. None of the deposits were found to have commercial value. The ore that was mined in the early 50s was trucked away for testing and processing by the AEC. That testing/processing was never done because larger/better deposits were found in the West. Granite will often produce radon gas, in fact granite counter tops can often yield small quantities. Around here most radon remediation is done because of granite bedrock. |
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Post by 1dave on Nov 9, 2020 9:50:43 GMT -5
As I recall ALL of our uranium came from a 6.6 BILLION year old supernova that flooded the nebula our solar system formed from 4.5 Billion years ago, so it was sparsely scattered through everything.
New Comets to the neighborhood wear down to Asteroids and Meteors - all containing a wide variety of elements. Occasionally one, or some, of them containing uranium + other stuff has slammed into the earth at diverse locations, leaving stuff that glows in the dark.
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lookatthat
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Post by lookatthat on Nov 9, 2020 11:04:58 GMT -5
Very cool -- I wish I could understand it.
The Upheaval Dome Cross-Section illustration is particularly telling.
But the damage afterwards reminds me of the Channeled Scablands and the failure of the dam at Glacial Lake Missoula.
Two other thoughts....
The aerial pics look so familiar... maybe I flew over this on my way back from California? (I flew out of Sacramento.) I took several pictures, but I don't have them here.
Second -- decades ago, my father was elk hunting with a friend "somewhere in Montana" and they came to a strange bowl-shaped valley... where their compasses thought all/any direction was north. What could have caused that?
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Post by 1dave on Nov 9, 2020 13:18:17 GMT -5
Very cool -- I wish I could understand it. The Upheaval Dome Cross-Section illustration is particularly telling. But the damage afterwards reminds me of the Channeled Scablands and the failure of the dam at Glacial Lake Missoula. Two other thoughts.... The aerial pics look so familiar... maybe I flew over this on my way back from California? (I flew out of Sacramento.) I took several pictures, but I don't have them here. Second -- decades ago, my father was elk hunting with a friend "somewhere in Montana" and they came to a strange bowl-shaped valley... where their compasses thought all/any direction was north. What could have caused that? It sounds like an Iron Meteorite impact site. The iron would mess up their compasses. |
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lookatthat
Cave Dweller
Whatever there is to be found.
Member since May 2017
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Post by lookatthat on Nov 9, 2020 15:19:25 GMT -5
That's what my father was wondering.
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stly 
WHAM!
