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A question for the masses...

If a meteorite has a terrestrial age of say 15,000-20,000 years old, and a prospector is finding meteorites on the surface, would it be safe to say that the topography hasn't changed in that length of time where the meteorite is found? Then that begs the question, what about finds that are 6" to 8" deep? Has the topography changed to cover them, or move them to the current location or did the meteorite impact the Earth so hard to bury them at that depth? I am trying to understand the Gold Basin strewn field and why some meteorites are buried several inches down, while other are still on the surface and the distribution to each kind, i.e. surface and buried.

From what has been posted in various articles, very many meteorites were found on the surface, but what about the ones buried? Were they cataloged as to how deep as well?

Just having too much time on my hands and wanting to go hunting in the field again... Jason :;):

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So put your woolies, gloves and ski mask on and go...oh, and a coat for your detector...

the answer is yes, no and maybe...let us consider that what the wind removes it may also replace...what the rain uncovers the runoff may recover...what was once a level plain may have tilted and developed gullies...earthquakes may have shaken larger pieces to the surface...everything may have been a mud bog when the Gb meteorite impacted...gosh, this speculation is fun when I have little else to do...

seriously, Jay, consider the terrestrial age and that it is a mere blink in geologic time, I would guess things were more or less the same as now but wind deflation and water erosion have been doing their jobs.

my 2 cents

fred

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I dont know about GB but the dry lakes wind water and sand storms are what bring the Stones to the surface. but places like Kansas or Glorita you are going to be digging so it depends on the local environment alot.

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FM, I guess the question is in the finding of the meteorites in themselves. Those found this weekend, the red "L" shaped one was on top of the surface, while the others were found subsurface to several inches down. The "L" one was on a flat area, pretty much at the end of a big wash. That being said, one would think it would be covered instead of on the top. While the others were on top of the ridges several inches down, with washes on either side. If I could get my head wrapped around it, then I might understand gold too, but I'm thinking that's probably a whole other discussion... Jason :;):

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Jason,

It is my belief that at Gold Basin, the elements such as weather and erosion play a big part. Vegetation is also a big factor. The base of every piece of vegetation out there is a soil trap, wind blown dust accumulates around the base of anything sticking out of the ground. Rodents burrow in these area's and increase the depth of the overburden. Most of the surface finds out there are found on the flatter pavements and most of the buried meteorites are in soil accumulation area's, such as the down sides leading into the drainage's. I have found many pieces at GB and also Franconia, that show a history of surface exposure (desert patina), only to have gotten buried by soil accumulation caused by one or more of the above explanations.

I know that you have probably suffered a slightly twisted ankle on more than one occasion in these sometimes rather large area's of soil accumulation, chock full of rodent tunnels and nests, not to mention all the rattlesnakes that seek shade in these area's.... :unsure: ...Is a real shocker when the ground drops out from under your foot.... :scare:

Congratulations on your successful recent hunt at GB, those are some real nice finds.

Jim

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Guest bedrock bob

Freeze/thaw cycles will bury an object in a hurry. When miost ground freezes it expands and heaves, then it thaws and the water trickles down a little and it freezes again. You can actually see the rocks inching down by the "ring" of dirt around them after a freeze. The top few inches "till" and mix things up pretty good. You could find an object like a hammer that was on the surface in the fall at 4" by the spring, especially under snow cover. It is not uncommon to find old rifle casings fired from the same rifle on the surface AND at 4" or deeper after just a few years.

It is mother natures way of tilling the soil and bringing up topsoil and it happens to some extent everywhere. It is why the pasture is muddy in the spring. In a heavily deflated area it works with the wind to constantly fluff up the soil in the winter for the wind to blow away in the spring. In a lot of places here it is the primary contributing cause of erosion...If it did not happen the wind would have nothing to blow away after a few years.

An object would not always rapidly disappear under the soil. It would depend a lot on its shape and density, as well as the composition and texture of the soil below it. So not everything will sink. Once a pavement is established things slow down a lot, but the cycles still continue to some extent. Vegetation (or the lack thereof) plays a big role in this process too.

I dont know how this would apply to Gold Basin in todays climate, but a lot has happened in 20,000 years and I would bet that in this time it has played a part, along with deflation, water erosion (or fill) and all the others. It is the main story here in the colder climates, and why a surface deposit of gold will be found concentrated at frost line.

Bedrock Bob

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Hi Jayray

Jim Kreigh, Twink Monrad, Dr. David Kring and I logged each and every find then quite at about 4000 pieces. An individual gram weight, locations ( most were in large groups) and aproximate depths of each piece. Dr Kring did several soil sample studies on the area as well. Dr Krings initially aged gold Basin at 35,000 years old but backed it off at the time of the publication . I know David had thoughts that much of the finds may have been transported to where they are now found. By water ,wind, ice or ?? We overwhelmed the U of A with specimens for study and they quite looking and logging them at around 1400 pieces. I think alot of that was what they had available in funds and grants for lab operations. Jim and I showed David many variable in the finds many of which torned out to be different finds or ended up classified by similar finds taken to UCLA. There has been an ongoing study being done in Germany about coralations between old finds and Lime Carbonate in the soil as a preservative. In Dr Krings publication at the time of the fall Gold Basin had a similar climate and vegitation as Wisconsin does now and there probably was glacial ice in the Hualipia valley . The average critter roaming the gold basin area were saber tooth cats. wholly mammoths, giant ground sloths and such( very few prospectors). It amazes me that any of the meteorites survived. We found several areas were the average find sizes were quite large( over 350 grams) and most were reasonably deep. Other areas were all pieces were buried but most of the ridges they were pretty much surface or shallow. The White Elephant is an L4 almost identical to the Gold Basin L4 yet the White Elephant aged at +or- zero date meaning a very fresh fall. The King tut was an L5 with a +or - 1000 years and a couple of the hualipia wash pieces are thought to pair with it. There are some areas were we found bucket loads of nice pieces and I would share them with you. But not on this forum with others trying to profit on our work. Even though the Gold Basin meteorite is thought to be a large homogenious mass consisting of L4 to L6 material there is no doubt many other fall scattered throught this feild and beyond. It is getting very hard to find labs to even classify new finds because of the shear volume of new finds. At the time of the Gold Basin find there were about 20 known meteoriite finds and one fall in Az. Now there are at least a hundred maybe 2 !! Ok so now please explain it all to me !! On another note Jim and I found meteorites there that we specked that won't make a fart on our GMs or any other detector. Yet they still had some magnatizm. We assume the metals within had rusted away or they were primarilly parts of achondritic clasts . It real hard to get to excited about huntin up there anymore. In the olden days during the hunt I had many 5 or 6 kilo mornings and would go back out and do it again in the afternoon as well. Happy Huntin John B.

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John, very interesting indeed. The transported theory is interesting but would think it illogical based on the pattern of the field as compared to other debris fields throughout the country and the world for that fact. Granted no one will ever know the true events that took place that day and rightful so, but it makes for some interesting conversations and insights to the field. The ridges, hills, and flats are quite unique in that they bare meteorites on such a different level, it's hard to keep track of it all. Thanks again for all the information, Jason. :;):

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Hi Again Jason

Based by a true elipse of the GB strewnfield it should include and stretch into the King Tut placer area ( the back or eastern side of the garnet mountains). We never did find any GB material in there or on the steep west facing slopes of the garnet mtns. We did find a few on the bases of those hills where it wasn't so steep. But there is a significant elevation and moisture difference between those two valleys with lost basin bieng much higher and wetter. The slopes of the garnet mountains are fairly steep. Which common sense would lead you to believe they would settle out in the rapidly moving soils. We did very little mountain goating into the steeper hills in search of stones for that very reason. On my last trip there I took Roger to one fairly steep hill that generated a lot of good pieces for us. I found a bunch of pretty lilac colored quartz float and followed it up this hill into a maze of space rocks. Twink was into pretty rocks and got all the quartz pieces I picked up. Believe it or not Roger actually found a couple of space rocks up there with his GM3 !! I believe that Gold Basin and Franconia strewnfields are only a couple of the many that exist in high lime carbonate deserts of the southwest. Many are probably desert varnished pavements that will be discovered once some time is spent beepin them. I can think of several occasions that my pionty finger started twiching as I was driving somewhere. Happy Huntin John B.

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