Naked Science Forum
Non Life Sciences => Geology, Palaeontology & Archaeology => Topic started by: OokieWonderslug on 14/05/2011 20:27:28
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http://maps.google.com/maps?hl=en&ie=UTF8&ll=35.770032,-80.294732&spn=0.00222,0.005493&t=h&z=18
I used to live within a mile of this spot. In the fall and winter it is extremely obvious that what we have here is part of a creek. A horseshoe bend of some kind. It's about 3 miles from the river and there is a small creek a mile away, but neither seem to be good candidates for having been in this spot at one time.
Since it's a surface feature, does that make it young? It's orientation (going into and out of the hill it's against) makes me think that water feature was here and then completely buried and then this was eroded out of the hill. I have spent many hours looking in the area and this is the only place where this feature shows up. You can't connect it with anything else. Is the rest of this river buried? What would bury a river? Wouldn't the flowing water just wash what was covering it up away?
What do you reckon I'd find if I could secure permission to dig out the center of this feature to the rock bed? Would there be fossils there?
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Ookie - did you ever try the old maps?
http://www.lib.unc.edu/dc/ncmaps/?CISOROOT=/ncmaps
I cannot post the exact link - cos it fills in a ten lines for some reason(browse -> search by county) . But some of the old davidson county maps seem to show the crossing of the railway and swearing creak (great name) with an east/west road of the correct shape to linwood. I have not been able to find anything with sufficient detail - but there might be others. If you have the time I am sure that one of the many railroad maps (that are at incredible scale) might just catch your area - these are 1850, and might show your feature as bog/marsh or something.
Thanks for posting picture - I love old maps and have just spent far too long looking at these great old maps of North Carolina, but it's half past midnight and apart from ploughing through a hundred unreferenced railway plans I have reached a dead end.
g'nite
Matthew
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Yes it is a bog/marsh. The farmer doesn't plant there very often. I think it gets too muddy to plant. Tar Creek is the closest creek to it. But what gets me is how it goes into and out of the side of the hill. There is over 50ft elevation difference from the bottom of the formation and the top of the hill.
If it is a "fossil creek", then why is it marsh like? Wouldn't that property of the soil have long gone away? Are there "fossil creeks" underlaying current strata still transporting water, but very small amounts and very slowly?
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I must be honest that the limits of my geology are pretty close to being able to spell geology! But what you are saying makes sense. One thing I would say is that there was clearly some active water management going on around the time the railroad was built(it seems the course of at least one of the creeks was changed) - and those guys knew how to shift vast amounts of muck. Some of the old maps show three creeks crossing that stretch of road - I might speculate that two got merged and your strange bog is the remnants of the lost one. Spoil from the railroad, the infill and farmer's ploughing has erased most of the traces apart from the lowest part which has stayed damp and unusable. Pure guesswork - but unless you fancy getting out there with a core sampler - that's all we can do.
Matthew
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The Saint is correct. There has been too much dirt moved to really tell what the hell is going on. It was a creek, there are remnants of creek both north and south (as well as two to the east so who know. Things can change rather quickly when man is involved.
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I really can't see that that much dirt has been moved in that area. The topography of the land doesn't jibe with there being that much earthworks there. That would be a huge amount of dirt to move and all the water ways around that area are much lower than the area I posted. The nearest creek is close to the level of the train tracks, but what I pointed out is a good 50ft above any tracks. Which is in itself another 50ft from the top of the hill. That would mean that 50ft of fill had been added over at least a couple square miles. That is a lot of earth moving.
I guess I have no choice but to take yall's word for it. At least until I get enough money to dig a core sample and carbon date any organic material I may find.
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By going to Google Earth and exaggerating the vertical scale, it becomes obvious that the low areas in the field are tributaries to the north flowing stream (across the highway, which then flows under I-85) The western tributary is a wide, flatter low-lying area, which could certainly be prone to wetter conditions. (north flowing stream with tributaries in field shown by white lines on google earth image).
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Oh ok. I see what you mean now. It's a spring that fed a stream. That makes a ton of sense. I wasn't seeing it and couldn't figure what you meant. But now that you've posted that it is obvious. I can't tell you how many times I have driven by that place real slow wondering what the topography was like when water flowed through that "stream".
You have to admit though, it does look like part of a creek that was buried and then exposed.
Does that ever happen like that?
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Absolutely. In fact, my first thought when I saw your image was old oxbows (cut-off river meanders).