This presentation examines Little Singletary Lake in North Carolina, which is in an area
where many of the geological principles of superposition can be observed in the emplacement
of the Carolina Bays.
Also, several sources of error are identified in dating the bays using Optically Stimulated
Luminescence or OSL.
Welcome to another edition of the Carolina Bay of the Day where we study the secondary
impacts made by the glacier ice boulders that were ejected by one or more extraterrestrial
impacts on the Laurentide Ice Sheet.
Today we will examine Little Singletary Lake which is located 28 kilometers or 17 miles
southeast of Fayetteville, North Carolina.
This area has a river, a creek, mud splashes, erosion and overlapping bays that can be explained
by several geological mechanisms.
In 2017, I proposed that the elliptical geometry of the Carolina Bays implies that these basins
originated as inclined conical cavities or penetration funnels made by secondary impacts
of glacier ice.
This makes sense because ellipses are conic sections.
Of course, not all Carolina Bays are elliptical, but many of the distortions can be attributed
to deformations caused by the properties of the terrain or to erosion by wind and water
after the basins were formed.
The formation of the Carolina Bays by impacts has been considered since the 1930s, when
the bays were first photographed by aerial surveys, but today, mainstream geologists
attribute the formation of the bays to gradualistic wind and water mechanisms which operated over
thousands of years.
This conclusion is based mainly on the results of dating the terrain by Optically Stimulated
Luminescence or OSL.
We will start by getting familiar with the neighborhood of Little Singletary Lake.
I am using the LiDAR visualization tool for Google Earth by Michael Davias.
There is a link to it in the description of the video.
The Cape Fear River and Harrison Creek are located to the west of Little Singletary Lake.
One of the first things that we notice in this landscape is that the area with the river
has just a few bays on the high ground between the river and the creek, whereas the area
away from the river has many Carolina Bays.
The lack of bays along the fluvial channels brings up the question of whether the entire
surface was bombarded equally by the glacier ice boulders ejected by the extraterrestrial
impact on the Laurentide Ice Sheet.
This is actually a trick question.
It is almost like asking if rivers get wet when it rains, but we know that rain falls
not only on the land, but on the rivers also.
The ejecta curtain from the extraterrestrial impact would have deposited a fairly uniform
distribution of ice projectiles in the area of 20 by 30 kilometers represented by this
image.
The Carolina Bays are fragile sandy structures that are easily eroded by horizontal water
flow, so we have to conclude that the Cape Fear River with all its meanders and the Harrison
Creek destroyed most of the Carolina Bays that existed in that part of the landscape.
One thing is to be able to deduce that there were impacts along the Cape Fear River and
another is to be able to prove it.
So, how do we know that there were impacts on the Cape Fear River and Harrison Creek?
We look for splashes of river sediment.
In this enlarged image, we see the mud splashes, also called splash chevrons, which were created
when sediment from the river and the creek was carried to higher terrain by wave action.
The impact of an ice projectile on a river bed dredges the sediment and deposits it on
higher terrain as illustrated here.
Splash chevrons are found on many coastal areas around the world.
The V-shaped sand deposits along the shoreline of southern Madagascar are thought to have
been created by tsunamis produced by tectonic activity that picked up sand from the shallow
seabed and brought it to higher ground.
Some scientists have suggested that extraterrestrial impacts in the ocean could also have generated
such tsunamis to produce the splash chevrons.
Little Singletary Lake also has a splash chevron.
This probably resulted from a small lake that was hit by the glacier ice boulder that made
this basin.
The chevron does not have high contrast in the LiDAR image because it is very thin.
The splash chevron can be seen more clearly in the satellite image because the white sand
of the splash contrasts against the darker background of the surface.
Notice that there are actually two splash chevrons by Little Singletary Lake.
Marshy Bay, which is to the northeast of Little Singletary Lake, has attracted attention before
because it overlays several Carolina Bays that are around it.
In 2006, the book by Richard Firestone, Allen West and Simon Warwick-Smith introduced the
Younger Dryas Impact Hypothesis and brought attention to Marshy Bay and a cluster of bays
in North Carolina with overlapping rims.
The book says: "Notice the fish-scale effect at the arrows, where a top bay overlaps a
middle one, which overlaps a lower one.
Of the eleven bays, ten overlap others or are overlapped.
Wind or water cannot create this effect, whereas an impact can.
This image highlights the sediment deposits made by the splashes of impacts on Harrison
Creek.
The deposits cover a strip of land almost two kilometers wide along the bank of the
creek.
These splash deposits attest to the bombardment on the creek.
Note that the bays labeled A, B and C cut neatly into the splashed sediment.
This means that these bays were emplaced after the splashes were deposited.
In the case of bay A we can see that the sand deposits stop abruptly at the margin of the
bay, which confirms the deposition sequence.
First the sand sheet was deposited and then an impact made bay A, according to the law
of superposition.
We can also see that the Little Singletary Lake basin was made before the bay labeled
A because the rim of bay A spilled into the Singletary basin.
At the beginning of this presentation, I mentioned that mainstream geologists attribute the formation
of the bays to gradualistic wind and water mechanisms.
Searching Google for the dates of the Carolina Bays, the first answer that comes back says:
QUOTE.
The dating of the sand rims of a number of Carolina bays by optically stimulated luminescence
(OSL) techniques has yielded ages ranging from about 109,000 to 2,000 years ago, but
most ages from the sand rims range from about 40,000 to 11,000 years ago.
END QUOTE.
The information comes from Wikipedia, so we can question its validity.
However, peer reviewed publications, like this one by Lundine and Tremabanis published
in 2021 say this about the Carolina Bays: QUOTE.
Many have argued, without substantial evidence, that they are meteoritic, comet, or glacial
ice impact craters, while others have tried to explain their origin using slower geological
processes tied to wind, waves, burning peat, and groundwater processes.
Sediments collected from Carolina Bays have returned ages ranging from over 100,000 years
old to within the last 5000 years, indicating that these features have undergone numerous
stages of genesis and modification.
The exact details of their dynamics, however, remain unclear.
END QUOTE.
The paper seems to favor wind and water mechanisms for the formation of the Carolina Bays because
it mentions that there is no substantial evidence for the impact hypothesis.
The wide range of dates from over 100,000 to 5000 years ago also seems like a reasonable
argument against the origin of the Carolina Bays during a single event until you examine
the limitations of Optically Stimulated Luminescence dating.
The geology department of Utah State University has detailed instructions for collecting soil
samples for dating by Optically Stimulated Luminescence.
The Optically stimulated luminescence (OSL) technique dates the last time sediments were
exposed to sunlight, which zeros the luminescent signal.
The luminescence signal grows with time due to exposure to radioactive isotopes within
the sediment and incoming cosmic rays.
The age is calculated by dividing the dose the sample received by the dose rate of its
depositional environments.
OSL is a very accurate dating technique when the proper sampling instructions are followed.
One of the instructions for OSL dating says to avoid sampling less than one meter below
the land surface due to difficulties in determining cosmic dose rate.
This requirement is probably responsible for the worst errors in dating the Carolina Bays.
This image of the Murray Springs Clovis site in Arizona shows the black mat that dates
to 12,900 years ago, which is the time of the Younger Dryas cataclysm that has been
proposed as the time when the Carolina Bays formed by secondary impacts of glacier ice
boulders ejected by an extraterrestrial impact on the Laurentide ice Sheet.
Notice that the black mat is about 2 feet or about 60 centimeters below the land surface.
Any OSL samples taken one meter below the surface will be far deeper than the surface
of 12,900 years ago.
This will cause the OSL dates to correspond to terrain that is thousands of years older
than the time of bay formation.
Another requirement for OSL sampling is to avoid bioturbated sediments that have been
moved around by burrowing animals or by plant roots.
The instructions clearly say that it is best to only sample sediments where you can see
primary sedimentary structures.
The accuracy of OSL depends on sampling layers of undisturbed soil deposited by sedimentary
processes.
This also implies that OSL should not be used on soil disturbed by the barrage of impacts
that created the Carolina Bays.
Unfortunately, the Carolina Bays have been dated by OSL as if they were sedimentary structures,
and this has produced a wide range of invalid dates that have been used to argue that the
Carolina Bays did not form contemporaneously.
Optically Stimulated Luminescence dating was intended for use on sedimentary structures
and it is inappropriate to use it on a landscape formed by a barrage of impacts that scrambled
the terrain.
Little Singletary Lake is located 1111 kilometers from Lake Michigan which is assumed to be
the point from which the ice boulder that made the basin was launched.
The basin has a width of 1,707 meters and a length of 2,905 meters.
With a length of almost three kilometers, Little Singletary Lake is not so little.
The width-to-length ratio corresponds to an impact angle of 36.0 degrees.
The diameter of the glacier ice projectile that made the basin is estimated to be 581
meters, which is one fifth of the basin length.
The smaller bay A is slightly more circular and it corresponds to an impact angle of 37.0
degrees.
The ballistic equations indicate that the glacier ice boulder that made Little Singletary
Lake was launched at a speed of 3.385 kilometers per second.
It had a flight time of 406 seconds and reached a height of 202 kilometers above the surface
of the Earth.
The trajectory was a suborbital space flight in the vacuum of space.
Notice that the ice boulder that made the small bay labeled A arrived 7 seconds after
the ice boulder that made Little Singletary Lake.
From the LiDAR image, we already know that small Bay A overlaps Little Singletary Lake,
but the geometry of the bay used to calculate the impact angle and the ballistic equations
confirm the sequence in which the impacts were made.
The kinetic energy of the impact that made Little Singletary Lake was equivalent to 129
megatons of TNT, which would have caused seismic vibrations of magnitude 8.89.
The small bay A was made by an impact with energy of 58 megatons of TNT.
The features of this landscape can be explained fairly well by assuming that the Carolina
Bays originated as inclined conical cavities produced by oblique impacts.
The transformation of the conical cavities into shallow elliptical bays by viscous relaxation
can be demonstrated by a physical model.
The splash chevrons adjacent to the river and the overlapping bays can also be explained
as the result of ballistic sedimentation of ice boulders ejected by an extraterrestrial
impact on the Laurentide Ice Sheet.
The impact model of the Carolina Bays can account for all the geological features.
However, it would be very difficult to explain all the details of this landscape if we assumed
that the Carolina Bays were created by wind and water mechanisms.
The greatest challenge would be to describe the physical forces by which wind and water
could consistently make shallow depressions with nearly elliptical geometry, including
in cases where the bays overlap.
In addition, wind and water mechanisms cannot explain why the basins from Nebraska to the
East Coast have radial alignment toward the Great Lakes.
Thank you for joining me in the investigation of the Carolina Bays and the Younger Dryas
cataclysm.
I will continue to examine the Carolina Bays one bay at a time.
My book about the Carolina Bays is available at Amazon.
Please subscribe to my YouTube channel to be notified of future videos about the Carolina
Bays.