Imaging 50,000 Oriented Ovoid Depressions Using LiDAR Elevation Data
Elucidates the Enigmatic Character of The Carolina Bays: Wind & Wave,
Or Cosmic Impact Detritus?
Abstract
80 years after aerial photography revealed thousands of aligned oval
depressions on the USA’s Atlantic Coastal Plain, the geomorphology of
the “Carolina bays” remains enigmatic. Geologists and astronomers
alike hold that invoking a cosmic impact for their genesis is
indefensible. Rather, the bays are commonly attributed to gradualistic
fluvial, marine and/or aeolian processes operating during the
Pleistocene era. The major axis orientations of Carolina bays are noted
for varying statistically by latitude, suggesting that, should there be
any merit to a cosmic hypothesis, a highly accurate triangulation
network and suborbital analysis would yield a locus and allow for
identification of a putative impact site. Digital elevation maps using
LiDAR technology offer the precision necessary to measure their
exquisitely-carved circumferential rims and orientations reliably. To
support a comprehensive geospatial survey of Carolina bay landforms
(Survey) we generated about a million km2 of false-color hsv-shaded
bare-earth topographic maps as KML-JPEG tile sets for visualization on
virtual globes. Considering the evidence contained in the Survey, we
maintain that interdisciplinary research into a possible cosmic origin
should be encouraged. Consensus opinion does hold a cosmic impact
accountable for an enigmatic Pleistocene event - the Australasian
tektite strewn field - despite the failure of a 60-year search to locate
the causal astroblem. Ironically, a cosmic link to the Carolina bays is
considered soundly falsified by the identical lack of a causal impact
structure. Our conjecture suggests both these events are coeval with a
cosmic impact into the Great Lakes area during the Mid-Pleistocene
Transition, at 786 ka ± 5 k. All Survey data and imagery produced for
the Survey are available on the Internet to support independent
research. A table of metrics for 50,000 bays examined for the Survey is
available from an on-line Google Fusion Table: https://goo.gl/XTHKC4 .
Each bay is also geospatially referenceable through a map containing
clickable placemarks that provide information windows displaying that
bay’s measurements as well as further links which allows visualization
of the associated LiDAR imagery and the bay’s planform measurement
overlay within the Google Earth virtual globe: https://goo.gl/EHR4Lf .