We wish to pursue the truth, no matter where it leads. But to find the truth, we need imagination and skepticism, both. We will not be afraid to speculate, but we will be careful to distinguish speculation from fact. – Carl Sagan, Cosmos Introduction.Our current goal is to spark interest in the Carolina bays among members of various professions. Our data is provided freely, and are open to direct collaboration, or to support your independent research.
What is a “Carolina Bay”, and why should one care”? The following quote is from the abstract of a 1998 PhD dissertation by Timothy D. Nifong:
Carolina bay depressions, once thought to number in the hundreds of thousands, are substantially rarer than previously believed. I estimate that fewer than 900 bay depressions with relatively unaltered site hydrologies remain within the study area. Those that do remain continue to disappear at an alarming rate. North and South Carolina bay depressions are important refuge for wildlife and for plant populations, including more than 65 "special status" plant species. Field observations and pertinent literature indicate that bay vegetation at relatively intact sites is highly dynamic, and that depression vegetation responds dramatically to differences in site disturbance regimes. Development of surrounding upland areas has resulted in increased isolation of Carolina bay depressions from the once pervasive role of fire as a landscape disturbance factor, and in the lowering of regional water tables. Consequently, bay vegetation has undergone an apparent "homogenization", with concomitant decreases in species richness and community diversity. If Carolina bay biodiversity is to be conserved and protected, increased and immediate attention must be given to prioritization, acquisition, and restoration of bay systems.My personal energies have been directed at socializing the bays - for the pressing ecological reasons, but also to encourage scientists in general to consider research into how they were created.
A session talk a poster were presented by me at the 2013 GSA Annual Meeting in Denver, CO. The talk attempted to review the derivation of the six bay planforms currently being utilized to measure Carolina bays in the Survey. Entitled, “A Proposed Taxonomy For Carolina Bay Circumferential Rim Planforms; Findings Of Robust Adherence To Distinctive Archetypes Is Supported By Lidar-Derived Digital Elevation Maps”, the link connects to the GSA abstract page, which hosts a link to an annotated PDF version of the slide deck. The poster, entitled Carolina Bays And Aeolian Dunes: Playing Nice In The Sandbox?, reviews the juxtaposition of aeolian dunes and Carolina bays in several settings. LiDAR imagery was used extensively in both the Poster and the Talk to support the discussions.
A poster was presented at the 2012 GSA Annual Meeting in Charlotte, NC. There we explored the Cape Fear River Falley and the terraces within, in an attempt to revisit David Soller’s observations regarding Carolina Bay ages. Entitled, Where The Bays Are: A Temporal Tale Of Carolina Bay Geomorphology As Told In Lidar By The Wando And Socastee Terraces, the link connects to the GSA abstract page, which links to an on-line version of the poster.
The 2012 GSA Southeastern Section Meeting allowed me the opportunity to present an oral talk on the subject SURFICIAL QUARTZ SAND DEPOSITS ON THE ATLANTIC COASTAL PLAIN: EOLIAN, FLUVIAL OR MARINE? THE CASE FOR A CATASTROPHIC DELIVERY MECHANISM. Link is to the GSA abstract page, which contains a link to the lecture slides and notes.
I presented an oral talk at the 2012 GSA Northeastern Section Meeting in Hartford, entitled LIDAR-DERIVED DIGITAL ELEVATION MAPS OF MARYLAND, DELAWARE AND NEW JERSEY USED TO IDENTIFY CAROLINA BAY LANDFORMS. Link is to the GSA abstract page, which contains a link to the lecture slides and notes.
We presented a poster at the 2011 GSA Annual Meeting in Minneapolis. The poster content, seen below, is also available as a PDF for download. I presented a TALK on the Survey and its use of LiDAR & Google Earth. A PDF of the deck is available HERE.
We presented a poster at the 2011 Southeastern Section GSA Meeting in Wilmington. The poster content, seen below, is also available as a PDF for download.
We presented a poster at the 2010 GSA Meeting in Denver. The poster content, seen below, is also available in a booklet PDF file.
We also had the opportunity to give an oral presentation on our use of LiDAR in this research at the 2010 GSA Meeting in Denver. A PDF of the presentation is available for download from HERE, or can be viewed as web pages HERE.
We attended the December 2009 AGU meeting in San Francisco, and presented a poster of our hypothesis as to the genesis of the Carolina bays and their role in identifying a possible North American Wisconsinian Ice sheet impact event.
A challenging aspect of the hypothesis involves the lack of an identifiable impact structure. The conjecture suggests an extremely oblique - nearly tangential-impact, and that terrestrial material ejected from such an event would be distributed in a stylized manner.Our analysis correlates numerous proposed ejecta material emplacements - including the Carolina bays and the Goldsboro Ridge - to a cosmic impact event that struck the Wisconsin-era ice shield at ~43°N, ~87°W. The proposed scouring action of the event is seen producing the current-day Saginaw Bay Basin. We have followed the chronological constraints to a proposed date of ~140 ± 10 thousand years ago.
If you are a Google Earth user, you can reference the Inferred Orientation of Distal Ejecta thread on Google Earth's Nature and Geography (Moderated) forum, or simply click the GE logo here to download a starter kmz.
The Enigmatic Sand: a Call for CollaborationOptically Stimulated Luminescence Dating (OSL) has proven to be a reliable method of dating sedimentary deposition timetables over the span of 1 kya to 100 kya. The process, which is well understood and accepted, is one which requires a rigorously controlled sample collection, handling and processing regimen. As such, it cannot be casually applied for testing across an extensive geography for research into a poorly-provenanced conjecture. The conjecture under consideration - our Saginaw Impact and Distal Ejecta Manifold - has minimal support in the community at present, yet we feel justified in the expenditure of the considerable resources suggested here.
We propose a scenario in which significant quantities of distal ejecta, in the form of a 1-10 meter thick sheet(blanket) of fine-grained sand, was deposited (blanketed) across a wide area for the North American continent in a singular event lasting less than an hour ~140 ± 10 thousand years ago (ka). During this blanketing, we propose that the constituents of the strata were heated to beyond 200 C, resetting their OSL clock. Identifying a coherent OSL dating across a wide field of samples would strengthen the case for our conjecture.
Our conjecture suggests that the resulting strata of sand - as a unit - can easily be discriminated from more generic fluvial and eolian deposit using a set of easily applied and identified criteria:
- located immediately below current A soil horizon
- homogeneous strata unit of 1 to 10 meters in thickness
- contact with underlying strata to be conformable and sharply defined
- blanket will drape over hosting terrain up-slope/ down-slope while maintaining strata thickness
- mottled, laminated or gnarly presentation in vertical and horizontal cross section, suggesting turbid deposit environment
- no indications of stratified horizons within the unit (single deposition sequence accepted)
- exception to above when multiple units of otherwise-qualified strata exists in contact with each other, generating a horizon
- no indications of aqueous deposition, i.e. shells, therefore deductively considered eolian
- virtually no clay lenses present
- incongruous course skew seen in unit
- tightly constrained grain size across unit
- grain size (as a unit) variable from exceedingly fine sand up to small gravels
- no variation in heavy metal suite across strata
- little variation in presented color across unit
Suggested sitings for this strata include:
- sourced from within the rim of a Carolina bay structure, or within a field of these structures
- Costal margins, where a truncated bay will be interpreted as a parabolic dune
- Late Pleistocene (MIS-3) -era deposits on elevated platforms where existence is enigmatic
- Surficial deposits may represent re-worked surfaces. We encourage sampling of rims at depths of a meter or more.
Ideally, samples meeting the above criterial would also have previously been tested to indicate:
• OSL dating of ca 140 ± 10 kya,
Due to the proposed geographic extent of this strata, we recognize it may well be considered "common" within your experience; yet enigmatic nonetheless in context, raising questions about the true depositional method.
Please consider the profile offered above, and should you have access to experimental datum derived from previous research which identified depositional strata meeting these criteria, we implore you to consider collaboration with us. In addition, should you have knowledge of , and access to, sites which exhibit these criteria, we invite you to assist us in obtaining OSL dating across the vertical and extent of the unit. Samples from depths of at least one meter are desired, so as to avoid reworked soils and encounter the original structural rim formation.
At present, the project is unfunded. Please contact us for more information.
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