Isopachous Map and Study on Thickness of Peorian Loess in Nebraska

An isopachous map showing the thickness of Peorian loess in most of eastern and southern Nebraska was prepared from test hole data secured in groundwater investigations. The data from over 1,200 test holes was plotted and isopachous lines were then imposed to show the relative thickness of the loess mantle. The deepest loess plotted was from 80 to 90 feet thick near the Sandhills and it became progressively thinner to the south and east. Immediately south of the Platte River valley the loess ranged from 40 to 60 feet thick and became thinner to the south and east. This study covered data for approximately 50 counties.