Antonio Zamora Podcast
Antonio Zamora Podcast

Antonio Zamora Podcast CB011

Carolina Bay Replication Challenge

This presentation discusses the modeling of Carolina Bays and challenges all persons to try experiments to replicate the landscapes of the Carolina Bays and to publish the results in peer-reviewed journals.

Carolina Bay Replication Challenge
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Carolina Bay Replication Challenge. This video discusses the modeling of Carolina Bays and challenges all persons who watch the video to try experiments to replicate the landscapes of the Carolina Bays and publish the results in peer-reviewed publications. It is time to stop watching YouTube videos and to start doing real research. Use your imagination to create convincing models of the geological mechanisms that created the Carolina Bays.

The experiments should use mechanisms that are found in nature, such as impacts, lightning, earthquakes, volcanoes, wind and water. Manipulating the surface to create shapes similar to the Carolina Bays by touching with the hands or tools invalidates the scientific experiment and turns it into an art sculpture. If you believe that the Carolina Bays were created by eolian and lacustrine mechanisms or by electrical discharges, by all means, design experiments to reproduce a model landscape of these geological formations using only the forces of nature in a manner consistent with the natural processes.

Once, I saw a video where a guy used a leaf blower to make an indentation on a sandy surface and he suggested that air bursts could have formed the Carolina Bays. It is not a bad idea, except for the fact that air bursts that can dig holes with diameters of many kilometers are not observed in nature. Tornadoes, which are the most powerful windstorms, are not known to dig elliptical structures like the Carolina Bays.

This is a LiDAR image of a landscape in South Carolina that has more than 20 Carolina Bays of different sizes. Using the law of geological superposition we can determine their sequence of emplacement. It is important to note that well-preserved Carolina Bays are elliptical in the mathematical sense. An ellipse with the same width-to-length ratio as a Carolina Bay will fit the bay exactly after rotating and resizing the ellipse. Here we can see that an ellipse fits precisely and follows the contours of the bay rim. The highlighted bay has a length of 1,200 meters. The width of the bay cannot be measured directly because a portion of the bay was overlaid by another bay, but because the bays are elliptical conic sections, it is mathematically possible to determine the shape of partially obscured bays from five points along their curves.

A Carolina Bay with a length of 1,400 meters overlaps the previous bay. The overlap means that it was emplaced later in time. We can also see that this bay overlaid a couple of small bays on its southeast margin. In order to replicate this landscape in a model, it is necessary to follow the same sequence determined from the law of superposition.

Most of the modeling work for the Carolina Bays has focused on making single bay structures, rather than a landscape of bays. In 1952, William Prouty considered that the Carolina Bays were created by a shower of meteorites from a disintegrating comet and that the sand-rimmed depressions were formed by the action of the air-shock waves associated with the falling meteorites.

Prouty argued that multiple and heart-shaped bays overlap in patterns explained most logically by the impact of tandem meteorites. He used a high powered rifle to shoot at a tray covered with a layer of plaster of Paris or flour at an angle of 35 degrees and a distance of 30 feet or 9 meters. In each case, the crater was made chiefly by the air-compression wave, which was many times the size of hole made by the bullet, as illustrated in this image. Prouty spent a lot of time searching for magnetic anomalies within the Carolina Bays to try to confirm his hypothesis about the meteorites, but he was not successful.

A thesis written by Raymond Kaczorowski in 1977 remarked that most workers seem to have neglected the concept of uniformitarianism in their studies of the Carolina Bays. Kaczorowski proposed that the bays were created just by the action of wind on pools of water, but he did not specify how the pools of water originated. He designed an experiment where a circular pool of water on a sand table was subjected to wind alternating in direction every fifteen minutes for four hours. The resultant shape was pointy like an American football, but Kaczorowski called it elliptical. He did not address the problem of how overlapping bays are formed. The thesis was never published in a peer-reviewed publication, but it is frequently referenced by proponents of wind and water mechanisms.

The fact that the Carolina Bays can be fitted with ellipses, suggests that the bays originated as inclined conical cavities because ellipses are conic sections. The Glacier Ice Impact Hypothesis, published in 2017, proposes that the Carolina Bays were created by secondary impacts of glacier ice ejected by an extraterrestrial impact on the Laurentide Ice Sheet. The ice impacts had enough energy to liquefy unconsolidated ground, and oblique impacts on a viscous target can be shown to produce inclined conical cavities that appear elliptical when viewed from above, as illustrated by this experimental impact. Adjacent oblique impacts on a viscous medium create inclined conical cavities whose overlap indicates the sequence of emplacement. In addition, viscous relaxation reduces the depth of the cavities to produce shallow elliptical bays.

As we have seen, each experiment tries to produce features analogous to the Carolina Bays using mechanisms that are consistent with the hypothesis being tested. Thus, the experiments use bullets and shock waves, wind blowing over pools of water, or impacts of ice on a viscous surface. Eventually, the method that is able replicate a typical Carolina Bay landscape has the greatest chance of leading toward the best hypothesis of bay formation.

The two large bays of the original landscape could be replicated by oblique impacts of ice projectiles fired at 39 degrees from the horizontal. The angle of inclination is calculated from the width-to-length ratio of the bays, which corresponds to the sine of the angle.

The second impact has to use a slightly larger projectile to account for the 200-meter difference in length of the Carolina Bays. The inclined conical cavity of the second impact also has to be close enough to the first impact to produce the overlap. The replication of this Carolina Bay landscape requires accurate shooting.

According to the Glacier Ice Impact Hypothesis, during the creation of the Carolina Bays, the saturation bombardment of the secondary impacts of glacier ice boulders created sufficiently strong seismic vibrations to liquefy saturated ground. Oblique impacts on the liquefied ground produced inclined conical cavities, and viscous relaxation driven by gravity and intensified by the seismic vibrations produced by the ballistic sedimentation decreased the depth of the cavities to create the elliptical bays in Nebraska and the East Coast.

Liquefaction can be accomplished in the laboratory by putting a container with sand and water on a shake table, but it is possible to dispense with the shake table by producing a viscous medium with equal parts of sand and pottery clay, and enough water to have the consistency of bricklayer's mortar. Without the clay, the sand quickly sinks to the bottom of the water, but the clay holds the sand in suspension.

In addition to the materials for making the target surface, it is necessary to consider the projectiles and the way of launching them toward the target. I have been using a slingshot and ice cubes made with molds of different sizes. Glass marbles can also be used as projectiles, but glass is 2.5 times more dense than ice and the cavities made by the marbles are deeper than the ones made by ice projectiles.

This is a LiDAR image of Kelly Bay in South Carolina. We can determine the mechanisms by which it was formed using the law of superposition and its geological setting adjacent to the Little Pee Dee river. The first feature of the landscape was formed when an impact created Kelly bay. Next, there were several impacts on the river bed. The edges of these impacts are still visible, but they have been greatly eroded. The impacts on the river bed splashed some mud on top of Kelly Bay forming the typical splash chevrons. A few seconds later, a tiny projectile fell on top of one of the chevrons and made a small Carolina Bay.

Although this seems like a complicated interpretation of this geological landscape, the same mechanism is observed at another location. This is a LiDAR image of Big Bay, also in South Carolina. Big Bay has a geological setting similar to Kelly Bay. Big Bay was formed by an impact adjacent to the Wateree River. There was also a large impact south of Big Bay. An impact on the Wateree river created a tidal wave that dredged some sand from the river bank. The wave carried the sand along fairly level ground and deposited it on the edge of Big Bay.

As in the case of Kelly Bay, a projectile with a higher trajectory impacted the layer of sandy deposits and made a small Carolina Bay. Kelly Bay and Big Bay are just two examples where we find splash chevrons overlaying bays adjacent to a river. The mechanisms that made this landscape seem fairly straightforward. First, an impact makes a bay next to a river, and then, an impact on the river dredges some sand and creates splash chevrons on the bay. It would be instructive to try to create this type of landscape experimentally. It is important to mention that the splash chevrons in Kelly Bay and in Big Bay are located to the east of the rivers. This characteristic may indicate that there were strong westerly winds at the time of the creation of the bays caused by the entrapment of the jet stream under the ejecta curtain of the extraterrestrial impact.

We prepare the target by spreading a thin layer of green sand on the surface to improve visualization. We can simulate a river by sculpting a trench on the target. A river should have additional liquid, so we pour water in the trench and create an area with a less viscous medium. We then add some red sand to this area. As in the case of Kelly Bay or Big Bay, we start by making an impact on the target adjacent to the river. Next, we aim some impacts toward the river and check to see if the splash covers the previously made cavity. In this image we see that the impact ejects some sandy material toward the previously made cavity on the green portion of the target. There is also a stream of red liquid that is ejected outside of the container.

The experimental result does not look like the landscape of Kelly Bay. The impact on the simulated river did splash some of the red material on the cavity on the green part of the target. The red material does not seem to have the correct consistency to make chevrons. The experiment could be improved by adjusting the viscosity of the red material so that an impact produces cohesive ejecta that can make chevrons. I hope that this video has encouraged some of you to try experiments to replicate the landscapes of the Carolina Bays and publish the results in peer-reviewed publications. Being able to replicate a landscape will demonstrate that the geological mechanisms that created the Carolina Bays are well understood and it will help to advance our knowledge about the bays.

© Copyright  - Antonio Zamora