[meteorite-list] Hilly billy vs flat land jokes-glacial
From: Elton Jones <jonee_at_meteoritecentral.com>
Date: Mon May 8 01:10:20 2006 Message-ID: <445ED2B6.7000105_at_epix.net> Gary K. Foote wrote: >I've had the same thoughts. Living in the mountains of NH I've thought there must be meteorites around here deposited by the past ice shield. They would be in the low lying areas more likely than the peaks and sloped sides of the mountains. JMHO > >Gary > MHO is that any non-iron meteorite would not have survived on the surface. The ice sheet most recent was 500-1200 ft thick over New England up towards the end, so those meteorites falling onto the ice would have not likely have reached the "ground" for several thousand years. Any concentrating mechanism will likely also concentrate other rocks as well. So you explore Eskers, Moraines, Kames, Drumlins and talus /scree piles If you are talking transported meteorites then you would be looking within moraines and or eskers in adjacent Massachusetts. The granite bedrock of the area was scoured. The soil there was reconstituted in the past 10,000?years. For perspective, meteorites which fell over present day New Hampshire: over 13,000 ybp would be in Martha's Vineyard as that lobe moved southeastwardly, between 13,000 and 8,000 ybp might be in Mass. Those under 8000 ybp might be found within recessive or lateral moraines. Otherwise those that were in transit by the ice would have settled to the surface where the thaw freeze cycle would have turned them into dust...er loess or drift. If meteorites fell on a glacial lake then there might be a "kame" deposit that is worth going through if it is being excavated. A kame is the inverted bottom of a summer lake that existed on the ice sheet and the sediments are loosely solidified. They are small hills( today which are frequently excavated for fill dirt. If the meteorite fell to ground ahead of seasonal ice advances directly onto the loess /outwash plane could have been preserved in situ during subsequent ice advances. This would be within a drumlin: similar in description to a kame but of a different origin. That said, yes the low areas for ancient falls, and anything after the ice sheet is going to behave like any other dislodged rock. Look somewhere within the talus pile at the base of the slope. However, the old adage is you find them where you find them. Trivia:If memory serves me, Nininger explored a possible fall in Maine within a bog/kettle lake. He found disturbed ground , debris splashed up onto tree bark and, broken limbs indicating something fell at a low angle and skipped along horizontally under the bank. After chasing a hole around 30 ft under the bank he ran out of pipe(?) and nothing was ever found to explain this splash. Total Trivia: South of Port Jervis/Milford on the PA/NJ/NY state line off I84 is a prominent escarpment I walk sections of hunting for fossils and meteorites and what ever else falls from the sky. I walk the base of the fault there looking for fossils dislodges from the face of the 400 ft exposure. When I first started, I noticed mini-slide trails from top to bottom and noticed at the end of each slide was a skeleton: turtles, deer, coyote, etc. I believe meteorites striking the face would behave in similar fashion. Elton Received on Mon 08 May 2006 01:10:14 AM PDT |
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