Cintos

Actually, I just now finished the last piece of my birthday cake! Yummy.. You have made a good observation. My point regarding the low angle and Ice is simply that if the object I propose had made a direct 90º strike, it would have sterilized the planet. The immense volume of terrestrial debris I propose did get excavated from an impact crater, the one at the locii of the triangulation network. Local ejecta would have landed on top of the glacial shield and eventually distributed as "glacial till". I noticed a discussion earlier in the thread about oblique impacts. Yes, Virginia, not all impact craters are round. 5% of all impacts on the terrestrial planets and moons have been identified as oblique, and they create a rather obvious signature crater: they are oval rather than circular, shallow compared to normal impacts, and the local ejecta is distributed in a butterfly pattern. Here is a crater on Mars: This crater is interpreted as having been struck from the top of the image, traversing towards the bottom, with a significant component of the impactor ricocheting back into space, out the ramp on the bottom. A unique situation, certainly, but there it is. My problem with a cometary airburst is that the structure of a Carolina bay does not suggest any deformation in either the underlying sediments, nor within the rims. The rims charmingly have no structure whatsoever - they are monolithic vertically and horizontally, with no perceivable layering. And, as I already noted, the chemical composition of the rims have no relationship the the underlying sediments. It is like they were poured into place from a giant cement truck. And while the bays clearly do suggest a "layering" of events in some locations, that can be easily address by waves of ejecta moments apart painting the same area. My "shallow" oblique impact crater has a depth that is 5% of the diameter. A 1KM Carolina bay that is 5 m deep is shallower by an order of magnitude. I am a fan of the Taurid Complex, but as a source of the major impact. One could speculate that the ricochet created the current stream of debris from the progenitor, and deflected the orbit of the complex into its current earth-crossing path. The attached KMZ file will open in Google Earth and place the Mars crater, above, on the Earth as an example. MarsCrater.kml

Greetings: Allow me to re-ignight this discussion. I just found the Hypography site and felt it may be a good place to hold a Carolina bay discussion with many folks who have an interdisciplinary interest in physics, astronomy and geography. I see Hill on the thread. He has helped me promote my working Hypothesis as to bay origins on the Google Earth Community Forums. I am including the quote By John L above, since it includes a facet which I feel is important to consider. In a nutshell, my suggestion does involve a cosmic impact, but with a significant twist. It has long been known that the bays are far too shallow to be impact craters. Also, the sand in the rim is typically much different than the underlying strata. I propose that the sand in which the bays are hosted is actually a blanket or sheet of distal ejecta, spread across the landscape at some distance from the actual impact site. I place that impact site far north and long ago, when the Wisconsinian Glaciation was in full force. A very shallow impact into 1 to 2 KM of ice would result in little damage to the earth, but spread a massive wave of very hydrated pulverized terrestrial material (i.e., sand) along an annulus surrounding the crater. Now, imagine that wave of ejecta as a foamy compote of superheated water and steam. As it strikes the ground, the imbedded steam bubbles burst, leaving behind a landscape dotted with small surface imperfections. Owing to the arrival angle of the ejecta, the momentum as it slides along the ground will stretch those bubbles along the arrival bearing. Attempts have been made to trace the orientations of Carolina bays, and have failed to provide a focus. None of those attempts considered ejecta trajectories over a rotating Earth. The Coriolis effect would steer the ejecta wave; that effect needs to be applied to the triangulation network to have a focus appear. I have been leveraging Google Earth, as it allows for the visualization of such a network upon a spherical playing field, rather than on a geographically distorted flat map. As John L noted, these effects would not be seen except on fairly level terrain. Elsewhere the sand sheet would simply erode off the slopes and not allow for the expression of a level rim. To enable the triangulation network, I have surveyed and documented 25,000 + bay landforms. The survey is hosted in a Google Fusion Table, and can be visualized as a map with placemarks HERE. Yes, I am suggesting the distribution of tens of thousands of cubic km of sand, and yes, this would have been a catastrophic event for the continent. I look forward to some spirited discussion!