Re: [Utah-astronomy] More on Upheaval Dome
Kim, as I recall you are right about Shoemaker being the first. --- kimharch@cut.net wrote: From: "Kim" <kimharch@cut.net> To: "'Utah Astronomy'" <utah-astronomy@mailman.xmission.com> Subject: Re: [Utah-astronomy] More on Upheaval Dome Date: Wed, 28 Jan 2009 10:15:10 -0700 I've missed some of this thread, and my memory may be faulty, but I thought that microscopic shocked quartz was first documented at Upheaval Dome by Gene Shoemaker, perhaps 20 years or so ago. I don't recall now where I learned that. Anyone else? Kim -----Original Message----- From: utah-astronomy-bounces@mailman.xmission.com [mailto:utah-astronomy-bounces@mailman.xmission.com] On Behalf Of zaurak@digis.net Sent: Wednesday, January 28, 2009 10:05 AM To: Utah Astronomy Subject: Re: [Utah-astronomy] More on Upheaval Dome Canyonlands certainly has no shortage of unique features not seen anywhere else. No virus found in this outgoing message. Checked by AVG. Version: 7.5.552 / Virus Database: 270.10.15/1921 - Release Date: 1/28/2009 6:37 AM _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com
I was just recently reading about interior mountains (central peak) within impact creators on the moon. As I recall (be on guard) I remember one writer saying that there were no interior mountains in creators less than 60 miles across. It seems that it takes a certain amount of size hence pressure to create a central peak. Just seems interesting that Upheaval Dome is barely 3 miles across and has a central peak, or does it? Maybe it is just the angle of Kurt’s photo. Jim Gibson
Jim, I feel sure there can be interior peaks in relatively small impact craters; it probably depends on factors like the material that was hit and the mass of the incoming object. As stop-motion photography of something as tiny as a drop of water proves, when a drop falls into a pan of water for an instant it forms a crater and an interior peak -- all water, of course. -- Joe --- On Wed, 1/28/09, Jim Gibson <jimgibson00@yahoo.com> wrote: From: Jim Gibson <jimgibson00@yahoo.com> Subject: Re: [Utah-astronomy] More on Upheaval Dome To: "Utah Astronomy" <utah-astronomy@mailman.xmission.com> Date: Wednesday, January 28, 2009, 11:10 AM I was just recently reading about interior mountains (central peak) within impact creators on the moon. As I recall (be on guard) I remember one writer saying that there were no interior mountains in creators less than 60 miles across. It seems that it takes a certain amount of size hence pressure to create a central peak. Just seems interesting that Upheaval Dome is barely 3 miles across and has a central peak, or does it? Maybe it is just the angle of Kurt’s photo. Jim Gibson _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com
Joe, I felt somewhat like you expressed about central peaks. When I read the comment about central peaks requiring a certain force I looked around on the moon and was surprised how many small creators didn’t have central peaks. There are also a lot of big creators with out central peaks either. So, I am still not satisfied that I know enough. You wrote Ø As stop-motion photography of something as tiny as a drop of water proves, when a drop falls into a pan of water for an instant it forms a crater and an interior peak -- all water, of course.< Ø < I love to watch that water drop too. I think you can see as well as I can that it requires a certain amount of liquidity or plasticity to make that central peak form. When a 1 km rock comes in at super hight speed it is not hard for me to imagine the punch it carries has the ability to turn rock into plastic for a short period. I just don’t know enough to say when or what threshold is required to meet those requirements. It was sure fun watching Shoemaker-Levey 9 punch into Jupiter though. So, I will keep gathering data on this as it comes along and maybe learn something along the way. Jim PS I remember watching Gene Shoemaker on TV shooting a high powered rifle from a high bluff down into a sandy wash then going down and inspecting the creators the bullet made. That was one techneque he used to study impact crators. --- On Wed, 1/28/09, Joe Bauman <josephmbauman@yahoo.com> wrote: From: Joe Bauman <josephmbauman@yahoo.com> Subject: Re: [Utah-astronomy] More on Upheaval Dome To: "Utah Astronomy" <utah-astronomy@mailman.xmission.com> Date: Wednesday, January 28, 2009, 11:55 AM Jim, I feel sure there can be interior peaks in relatively small impact craters; it probably depends on factors like the material that was hit and the mass of the incoming object. As stop-motion photography of something as tiny as a drop of water proves, when a drop falls into a pan of water for an instant it forms a crater and an interior peak -- all water, of course. -- Joe --- On Wed, 1/28/09, Jim Gibson <jimgibson00@yahoo.com> wrote: From: Jim Gibson <jimgibson00@yahoo.com> Subject: Re: [Utah-astronomy] More on Upheaval Dome To: "Utah Astronomy" <utah-astronomy@mailman.xmission.com> Date: Wednesday, January 28, 2009, 11:10 AM I was just recently reading about interior mountains (central peak) within impact creators on the moon. As I recall (be on guard) I remember one writer saying that there were no interior mountains in creators less than 60 miles across. It seems that it takes a certain amount of size hence pressure to create a central peak. Just seems interesting that Upheaval Dome is barely 3 miles across and has a central peak, or does it? Maybe it is just the angle of Kurt’s photo. Jim Gibson _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com
More from the depths of my memory. A water drop into a film, on a flat surface, will rebound in a ring, rather like a crown. No peak. A water drop into a deep puddle, will rebound a drop back up. Peak. So I'm surmising that you will get a central peak in a crater if the structure of the ground at ground zero has the proper rebound characteristics. This is probably at least as important as mass of the impactor. Also remember that many craters on the moon have been flooded with lava since they first formed. Some of them with central peaks had the peaks completely covered. They are still there, but buried under a sea of frozen lava.
Chuck you wrote:
Also remember that many craters on the moon have been flooded with lava since they first formed. Some of them with central peaks had the peaks completely covered. They are still there, but buried under a sea of frozen lava. I read an article that purports the unusual case where Piton, a skinny mountain peak south of Plato, is a central peak. The creator rims have been flooded away by lava just leaving the central peak sticking up…cool. One comment on the water droplets. We always see them come in at 90 degrees or perpendicular to the water surface. I suspect that may play apart in moon cratering too. Those that obviously come in at an oblique angle seldom leave a central peak but something that looks more like a key-hole. Jim
--- On Wed, 1/28/09, Chuck Hards <chuck.hards@gmail.com> wrote: From: Chuck Hards <chuck.hards@gmail.com> Subject: Re: [Utah-astronomy] More on Upheaval Dome To: "Utah Astronomy" <utah-astronomy@mailman.xmission.com> Date: Wednesday, January 28, 2009, 4:15 PM More from the depths of my memory. A water drop into a film, on a flat surface, will rebound in a ring, rather like a crown. No peak. A water drop into a deep puddle, will rebound a drop back up. Peak. So I'm surmising that you will get a central peak in a crater if the structure of the ground at ground zero has the proper rebound characteristics. This is probably at least as important as mass of the impactor. Also remember that many craters on the moon have been flooded with lava since they first formed. Some of them with central peaks had the peaks completely covered. They are still there, but buried under a sea of frozen lava. _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com
The San Rafael Reef that edges much of the Swell has miles of rock formations standing nearly on end. I was told more than 20 years ago by a well-known geologist that the Swell was part of the widespread geological process that formed the Rocky Mountain. But does anyone think the San Rafael Reef could be the rim of an impact crater? Just wondering -- Joe
Hi, Joe. I understand that the process that formed the San Rafael Reef/Swell is tectonic plate subduction, and I believe that Capital Reef was formed the same way, if that's the correct term. (Are smaller geologic plates still "tectonic" plates? Who are our resident geologists?) Kim -----Original Message----- From: utah-astronomy-bounces@mailman.xmission.com [mailto:utah-astronomy-bounces@mailman.xmission.com] On Behalf Of Joe Bauman Sent: Wednesday, January 28, 2009 12:03 PM To: Utah Astronomy Subject: [Utah-astronomy] San Rafael Swell The San Rafael Reef that edges much of the Swell has miles of rock formations standing nearly on end. I was told more than 20 years ago by a well-known geologist that the Swell was part of the widespread geological process that formed the Rocky Mountain. But does anyone think the San Rafael Reef could be the rim of an impact crater? Just wondering -- Joe _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com No virus found in this incoming message. Checked by AVG. Version: 7.5.552 / Virus Database: 270.10.15/1921 - Release Date: 1/28/2009 6:37 AM No virus found in this outgoing message. Checked by AVG. Version: 7.5.552 / Virus Database: 270.10.15/1921 - Release Date: 1/28/2009 6:37 AM
Calling Rodger Fry... On Wed, Jan 28, 2009 at 1:17 PM, Kim <kimharch@cut.net> wrote:
Hi, Joe. I understand that the process that formed the San Rafael Reef/Swell is tectonic plate subduction, and I believe that Capital Reef was formed the same way, if that's the correct term. (Are smaller geologic plates still "tectonic" plates? Who are our resident geologists?)
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