Carolina Bays

Mat h physics

Who may know some details about the Carolina Bays?

http://en.wikipedia.org/wiki/Carolina_bays

or other odd formation on the earth.

Astronuc

In what information is one interested?

http://www.srel.edu/outreach/factshe...olinabays.html

http://www.epa.gov/owow/wetlands/pdf/CarolinaBays.pdf

http://www.carolinanow.com/recsites/carolinabays.htm

The bays are found from Delaware to Florida, with a concentration around N and S Carolina.

Dotini

Hi Mat,
It appears you would like to know the origin of Carolina Bays, which formed on earth prior to the Holocene. The wikipedia entry you linked mentioned two broad categories of possible origin - that "these features were created by forces within the Earth, or that they were gouged by an astronomical event or set of events". The wiki entry concluded by rejecting the impact hypothesis, as you note. However, the geomorphology explanation runs into troubles, too, for instance the wiki reference to the spring sapping ideas of D.W. Johnson, "The Origin of the Carolina Bays" New York: Columbia University Press, is refuted as violating the conservation of energy, http://www.jstor.org/pss/30071107. So you do have a credible mystery here.

As an alternative, *Corliss cites the research of Y. Otsuki, physics professor of Waseda University, into plasmoids (to include plasma vortices), which hint at a sort of impact, not merely ballistic, following on from air bursts. For instance, a body disintegrates, say icy charged hailstones produced in the ionosphere, producing an ion trail to ground, resulting in something like lightning and its effects. In order to apply, these effects must have existed on scales larger than lightning effects known to occur now in the Holocene.

*"Science Frontiers: Some Anomalies and Curiosities of Nature", William R Corliss

Respectfully submitted,
Steve

Astronuc

There is plenty of time for erosion and accumulation of organic matter. The fact that they fill with water means that rocks and minerals would be carried to the depressions and accumulate over time. Then vegetation would grow in the water or along the banks, and sooner or later die. Leaves from deciduous trees are shed annually, so they would accumulate in the water. Nor surprises there.

Andre

There are threads about that this for insance

There are more problems

As for the Carolina bays, there is no point in speculating. That has been done ad nauseum.

Cintos

It has been well shown that the gentle depressions are unlikely to be impact structures, for many reasons - depth-to-diameter ratio being only one aspect. Douglas Johnson, in his 1942 tomb on the subject of "The Origin of the Carolina Bays" cited numerous additional reasons why his findings were not supportive of an impact mechanism. Among those is an observation that the sand in the rim and comprising the sheet of sand surrounding the bays has no direct relationship to the strata beneath the bays, nor are those strata disturbed by the presence of the overlying bay. Johnson also noted that antecedent drainage channels mapping through numerous bays seemed to have survived the creation of the bays, something that would be unlikely if they were carved out by impact processes.

You might get an interesting perspective by viewing the bays in high-resolution LiDAR-generated digital elevation maps.
- Michael

DoggerDan

Are they odd? Similar features are found throughout the world in low-lying coastal areas. Louisiana's swamps are very similar.

Cintos

The "Citronella" ponds in LA have been mentioned in listings of CB-like structures in the US. I have not identified any publicly available LiDAR in those areas of LA to inspect for the robustness of planform shape seen in further east.

Oriented lakes in the Siberian Arctic have a similar presentation to those in Alaska and the NWT, and oriented oval lake collections have been reported in South Africa, Australia and Argentina. The creation of similar structures right along coastlines (see attached from Siberia) seem the most similar to Carolina bays in shape - geometrically pure shapes. The shoreline process was discussed by Cooke in 1934, where he proposed Atlantic shoreline lagoons morph into chains of lakes. I find it quite persuasive, as did many others back in the 30's and 40's. As the identification of Carolina bays continued inland and into higher elevations, it lost favor. Today, bays are found on a continuum up to 200m elevation in the Carolinas, and the Atlantic has not visited those areas for over a million years.

Douglas Johnson, in his 1942 book on the bays, made a statement that has been a guiding principle for me:
Billings, Siberia, Russia from Google Earth

DrClapeyron

Is there any debate on whether these structures could be the reslt of salt tectonics? I did a google search for the Carolina Bays and any drilling activity, but a first search did not reveal anything significant. You think it would be easy enough to run a siesmic survey to see if there are any unusual changes in velocity, and try to correlate this to salt tectonic induced faulting. Or to run a gravity survey to detect any anomolies that could represent a bulb or stock or any sort of diaper, but there is not much available through simple google searches.

Oil and mineral companies must not fund a whole lot of research into finding what is below the Carolina Bays, which are present from Deleware to Georgia. I am not 100% convinced about the impact theory without some real hard evidence to show that these bays are not salt tectonic structures, or soft-sediment deformation structures caused by a massive earthquake as a result of forces between the down going oceanic crust and the floating North American crust.

DrClapeyron

I walked into the discount bookstore the otherday and found myself a like-new copy of the Roadside Geology to South Dakota. I never had much interest in glaciation, I bought the book to read about the Blackhills, however, looking at aerial photos and topo maps of glacial lakes/outwash I began to question my previous thoughts on the Carolina Bays.

While imagining how these small lakes would form, a thought popped into my head: maybe the bays are area that small glaciers deformed the ground where small glaciers once sat. Perhaps the glaciation east of the Appalachians was less mature than what happened between the Appalachians and the Rockies. This would explain why there aren't eratics or moraines present in the area.

So after doing a quick google search I found (and had suspected that hopefully) someone had beaten me to it.

http://www.evolutionaryleaps.com/Rea...ial_origin.htm

If this idea has any merit to it takes away a lot of the luster of an impact origin, and should raise the issue of a sort of mutual evolution of the bays through both glacial cycles and hydrological cycles.

Studiot

I wonder if there is any connection to pingo landscapes.

http://www.google.co.uk/search?q=pin...g&ved=0CFcQsAQ

Remenent pingos can be found in S Ireland.

Andre

It has been considered here, but

DrClapeyron

Thank you for the information Andre. I had to crack open my books to relearn some of these concepts like skewness.

Until the recent East Coast earthquake I was unaware that earthquakes could be felt so far away from their epicenter. This is because East Coast rocks are not deformed to the point where they have been brecciated and heavily fractured. So they are extremely good conductors, they do not absorb kinetic energy as well as their West Coast brethren.

Taking this information into account and some of the stories from the New Madrid earthquake of 1811 (sand volcanoes) I think earthquake induced soft sediment deformation leading to the formation of the Carolina Bays should be taken into question. Maybe this has something to do with the artesian wells theory, could you help me out Andre?


Could a large earthquake 12,000 years ago have liquefacted underlying water laden sediments to form plumes leading to the formation of the Carolina Bays? I have seen truck-size ball and pillow structures but I admitt to never having seen such structures close to the size or extent of the Carolina Bays.

Cintos

Greetings: There were significant sightings of sand volcanoes (sand blows) in the Charleston vicinity after the 1886 quake. The concept is quite intriguing, when consideration is given to quakes substantially stronger over the last 200,000 years. Have a look at this page: Tehrkot Media Historical Imagery for a photo of a fresh blow in South Carolina.

If earthquakes were involved, the timing constraint dictated by the lack of bay landforms on sandy surfaces created over the last 150,000 years remains, such as the Wando surface (see Soller, USGS Professional paper 1466-A, 1988). i.e., no "Carolina Bays" were created in 1886.

The Carolina bay landforms in the Midlothian, VA, area, are sandy-rimed oval landforms resting on a gravel base. The local geology there would not support a sand blow geomorphology. Also challenging for a sand blow genesis are bays measuring over a few tens of meters across - of which there are significant quantities.

- Michael

betzalel

The Firestone Younger Dryas paper alleges there is evidence of high temperature residue at the Carolina Bay elliptical marks which is similar to the high temperature residue that has found throughout the Northern Hemisphere that coincides in time with the occurrence of the Younger Dryas.

The Firestone paper hypotheses that the Younger Dryas high temperature marks were caused by a comet that broke up and then struck the planet in multiple locations throughout the northern hemisphere. The comet hypothesis does not explain how the Younger Dryas event caused abrupt cooling of the planet for a 1000 years. (An impact event would cool the planet for 3 to 5 years, due to dust and sulfur dioxide after which it would return to warming.)

As noted the Carolina Bay elliptical marks are significantly older (30,000 years to 60,000 years before present) than the Younger Dryas abrupt cooling event (the Younger Dryas event occurred 12,800 years before present.) There are roughly 1/2 million Carolina Bay marks. A comet could not cause 1/2 million marks on the planet.

In the last 10 years, geomagnetic specialists have found evidence of cyclic geomagnetic excursions (during a geomagnetic excursion the geomagnetic field develops multiple poles and the field intensity drops by a factor of 3 to 10). A geomagnetic excursion is capable of abruptly cooling the planet by Svensmark's mechanism. (The cooling pattern during an excursion is complicated as there are multiple poles formed which causes both increases and decreases in galactic cosmic rays (GCR) depending on the location of new temporary pole.)

There are geomagnetic excursions at the termination of the past interglacial periods and at the Younger Dryas.

The Carolina marks are overlapping, elliptical, with an axis that is alligned in the North west direction.

http://www.pnas.org/content/104/41/16016/suppl/DC1#F7

Quote:
Is the geodynamo process intrinsically unstable?

http://eprints.whiterose.ac.uk/416/

Dotini

Thank you for a very interesting post.

I agree that a reduction of the geomagnetic field could cause cooling via the Svensmark mechanism. But I'm not the sharpest tool in box, and fail to see the connection to Carolina Bays. Could you be bit more explicit about this, please?

Respectfully yours,
Steve

Andre

Earlier research did not find any corrolation between paleo magnetic excursions and general atmospheric conditions.