"Could the Meridiani Spherules be Surficial?" |
"Could the Meridiani Spherules be Surficial?" |
Jul 10 2007, 04:37 PM
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Junior Member Group: Members Posts: 42 Joined: 2-July 07 Member No.: 2646 |
I have been reading the response to the reponse to impact-surge linked by Dr Burt in post 170. The MER team objects to the impact-spherule explanation because " The spherules are dispersed nearly uniformly across all strata." I agree that is a valid criticism. It is very much like Dr. Burt's criticism of the MER team's hypothesis, that spherule distributions are not consistent with any conceivable ground-water movement regime that should have controled the development of concretions. I agree strongly with this point of Dr. Burt's as well. Neither theory does a good job of explaining the distribution of the spherules. Also, neither theory does a good job of explaining why the spherules do not apparently disturb the bedding.
There may be a solution in a possibilty that I now raise with some trepidation. I think that there is a chance that the spherules are superficial, and not an integral part of the Meridiani strata at all. This probably sounds crazy to many readers, but before rejecting it outright remember that science is at kind of an impasse on this and could use a new idea. If the spherules are superficial this would explain a number of puzzling observations. The layering at Homeplate and Meridiani is most simply explained by impact-surge. It is elegantly and inescapably explained by impact-surge. The impact-surge authors have also tried to explain the Meridiani spherules as part an impact event. If doubts are raised that the spherules are integral to the deposit, this would not in any way be inconsistent with the impact-surge origin of the layered structure. On the contrary, an objection to impact surge would be removed. I intend to start another thread under Opportunity to discuss this question. The first posting should be mine and should be an organized outline of how it might be possible that the spherules have been mis-interpreted as part of the Meridiani layered deposit. I am working on it. If anyone wants to start in on me with the obvious objections, do it here for now. Maybe Dr. Burt would like to respond. No matter what the details of spherule formation in an impact or spherule deposition in the impact sediments, the very uniform distributions that we see are troublingly unlikely. Random distributions are possible from explosive dispersal but less likely than some kind of clustering because of the rapidly changing conditions in the surge cloud. The more-uniform-than-random distributions of spherules on rock characterised by MER-team analysis cannot be explained by impact surge. |
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Jul 13 2007, 09:17 PM
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Member Group: Members Posts: 258 Joined: 22-December 06 Member No.: 1503 |
I think Mars is throwing us another 'monkey wrench'. It might be possible that longer range interaction between spherules was in effect in the recent past.
http://www.unmannedspaceflight.com/index.php?showtopic=4397 If the CO2 ice cap at the south pole only started forming within the last 1k years, then the Martian atmosphere must have been thicker in the recent past. This is a possibility that I never considered before. So the MER team might not be as far off the mark concidering distribution as they first might seem. Back to your idea of a some sort of surface event creating the spherules. I don't see how; but let's assume that something did happen. That would mean a drastic change in the atmosphere of Mars in relatively recent times. The only thing plausible I can think of is some sort of volcanic event. But there are no known volcanoes anywhere near Meridiani. Is it possible that some massive hydrothermal event occurred? ...something so massive that the atmospheric temperature around Meridiani reached about 300 Celsius? We now have good evidence of possible hydrothermal activity at Gusev. Why not a much larger network at Meridiani? (I have my doubts like probably most others reading this. I'm just brainstorming). Edit: One thing about the hydrothermal event idea is that it didn't have to happen recently to have created the temperatures necessary for the creation of the spherules. |
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