LiDAR Imagery - It’s a Beautiful World
The survey is enabled with LiDAR imagery. This relatively new technology allows the production of Digital Elevation Maps (DEMs) which have spectacular fidelity, often being able to discriminate elevation changes of only a few tens of centimeters, with spatial resolution measured in 2 to 3 square meter grids. For a great overview of the technology, you might start with this discussion about the Coastal Georgia Elevation Project .
Examples of LiDAR imagery of the Carolina bays
This page contains numerous samples of LiDAR imagery created for our survey. In most cases, a link is provided to high resolution artwork for your reference and enjoyment.
This Digital Elevation Map covers ~ 675 square km centered on Rex, NC (Robeson County), and was generated in the Global Mapper GIS program using LiDAR data from the USGS. The colors shown are an indication of topographic elevation, from 16 m AMSL in the lower right, to 76 m in upper left. Vertical resolutions of centimeters allow for visualization of the form and extent of the bays’ otherwise imperceptible rims. Rockfish Creek flows along the northern edge. CSX’s Atlantic Coast Line rail bisects the area diagonally along a strikingly straight right-of-way; Interstate 95 winds N-S on the right. The KML is available for visualization in Google Earth HERE. This image was awarded First Place, Abstract Images, at the GSA 2010 Fall Meeting’s Photo Contest & Exhibition. The image is also used in the GSA 2012 Wall Calendar, as the graphic for the month of November.
Carolina bays (Image linked to high resolution version) 17 miles x 15 miles (27km x 24km)
The source TIFF file for the above DEM is 36” x 24” at 300 DPI. As an example of the detail it contains, please reference the image below. The area it elaborates on is just right of the center of the image above.
The image below is from immediately west of the image above. The image was edited to change the hue of the heart-shaped bay, but not its shape. The KML to visualize this area in Google Earth is available HERE. A high resolution version is available HERE.
Heart of the Carolina bays
For another view of the heart, here is the view in the Google Earth Plug-in HERE
Again, the source DEM map holds significantly more detail than can be presented here. The image below shows the heart bay in more detail:
This map is from the area surrounding the Goldsboro Ridge (which crosses left to right at the center), in North Carolina. A 300 dpi 20”x11” high resolution version (22 MB) is available HERE. Research by Raymond Daniels, et al, on the ridge, was the inspiration for our ejecta deposition hypothesis.
The Goldsboro Ridge
This map is from the Hopewell area, just south of the Goldsboro Ridge image above. A 300 dpi 20”x11” high resolution version (22 MB) is available HERE.
The map below is from the Fayetteville, NC 100K quadrant. A 300 dpi 20”x25” high resolution version (95MB) is available HERE.
The large bay at the top of the above image is located just south-east of Benson, NC. The landform is quite complex, with indications of multiple smaller bays fully embedded within the larger one. The image below highlights this area, and a higher resolution version (8.6MB) is available HERE.
The image below is from the Bennettsville, South Carolina region. A high resolution image (2MB) is available HERE.
The image below is from the Quitsna, North Carolina region. A high resolution image (10MB) is available HERE. An interesting feature is that the two bays here seem to exist on top of the ancestral fluvial fabric.
Another “river bay” image below is from the Conetoe, North Carolina area. A high resolution image (10MB) is available HERE. These assortment of bays here exits mid-stream across a large drainage basin.
Here are bays on a peninsula between the bays ... image below is from the Currituck, North Carolina area. A high resolution image (9 MB) is available HERE.
Close up images of bays in South Carolina reflect the higher LiDAR resolution available with new LiDAR vs the 10-year old data from North Carolina... image below is from the Benson, South Carolina area. A high resolution image (3 MB) is available HERE.
In many areas bordering river valleys, sand dunes can be seen moving west-to-east across the bays. Often the bay survives the invasion... image below is from the Georgetown, South Carolina area. A high resolution image (13 MB) is available HERE.
One intriguing aspect of the bay formation mechanism, is that it was elevation agnostic... It seems unlikely their formation was controlled by either sea level or water table. The DEM map below is from the Latta, South Carolina area. A high resolution image (16 MB) is available HERE.
Here is another “elevation agnostic” demonstration. The LiDAR map below is from the Cordova, South Carolina area. The bay in the dark blue hill top at the upper left is at 95 meters above sea level. Those near the bottom are at ~40 meters, giving a relief of over 50 meters across less than 20 Km. A high resolution image (8.7 MB) is available HERE.
Nebraska’s Rainwater Basins are similar to Carolina bays in many aspects. A high resolution image (22MB) is available HERE.
It is well known that “Carolina bays” exist far north of the Carolinas. In Virginia, Maryland and New Jersey, they become more rounded, confounding the search for an obvious orientation. We see the bays forming a “bell” planform, with the narrow top pointing back along the orientation, and the wide base at the far end of the structure.
Here is an area of Virginia know as the “Eastern Shore” in 1/9 arc second LiDAR A high resolution image (100 MB) is available HERE.
Eastern Shore of Virginia
Another Eastern Shore LiDAR, at the center of the image above. A high resolution image (32 MB) is available HERE.
Eastern Shore of Virginia, Detail
For even more imagery from the Eastern Shore of VA, please reference our page HERE.
Here is an area of northern Maryland in 1/9 arc second LiDAR A high resolution image (15 MB) is available HERE.
Another Maryland LiDAR, just south of the one above. A high resolution image (15 MB) is available HERE.
Moving even further north, we find even ore of these “bell” shaped bay formations along the Eastern shoreline of the Delaware River, immediately around the Delaware Memorial Bridge crossing of Interstate 95. The first image provided here is the the overall area, and a high resolution 8x10 300 dpi image is available HERE.
Delaware Memorial Bridge
Below are three interesting areas from the above LiDAR.
Just short of the last glacial maximum advance in New Jersey, we find numerous bays. Here is a LiDAR elevation map showing the region near Red Bank, NJ. A higher resolution version is available HERE.
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