![]() ![]() As is the case in the east, the deposition of basins is seen on a continuum without regard to elevation. ![]() Bay floor elevations range from 535 MASL to 495 MASL over a distance of 32 miles. Here is an example of the Genera, NE region. We interpret this to be an effect of the "blanket" draping over previous landscapes. ![]() Our use of elevation data includes the generation of "elevation profiles", which attempt to relate the disparate altitudes of bays in a region. The image is linked to a higher resolution version. Here is a HSV-shader map of the Clay Center area. We are in the process of leveraging these for better quality images and for the location of additional bays that did not appear on the USGS 1-3 arc second data originally used here.Ĭorrelation of Nebraska bays with Carolina bays & Saginaw Impact The Nebraska Department of Natural Resources (NE-DNR) has released high-resolution LiDAR datum for much of the souther ares of the state. Since that time a significant blanket of late Wisconsin glacial loess have been deposited, rounding off the sharp edges of the bay rims, In some ares local dunes have breached the landforms, but the underling structure continues to show through. We speculate that the bay depressions were created upon ejecta deposition sometime prior to 27 kya. George Howard was the first to web-publish high resolution LiDAR images of bays in Nebraska. A relationship between the Rainwater Basins of Nebraska and the Carolina bays was first described by William Zanner (GSA Annual Meeting, 2001). While not nearly as extensive as those in the East, we hold the identification of these bays to be critical to the impact site triangulation process, as contrasted with their eastern-US brethren. Our interpretation is that the "inferred alignment" of all the Nebraskan bays we have identified are aligned towards the Saginaw impact site, and are correlated to a high degree using the Bearing Calculator tool. Significantly, the inferred alignment is considerably different from that of the background predominate-wind orientation of the extensive sand dunes in the area. While there is a great deal of research covering the "Carolina bays" on the eastern seaboard of the US, little attention has been paid to the significant quantity of oval-shaped landforms in the eastern areas of Nebraska. ![]()
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