An alluvial plain of a river
The 
work of large rivers (including the Mississippi, Arkansas, White,... [DOC] [TLE] Mississippi River Alluvial Plain Ecoregion // LandScope America [PAR] The most defining feature of the Mississippi River Alluvial Plain, which sprawls 
across parts of seven states from southern Louisiana to southern Illinois, is the... [DOC] [TLE] Mississippi River Alluvial Plain - Arkansas Geological Survey [PAR] The Mississippi River Alluvial Plain is a relatively level plain with elevations 
varying between 100-300 feet except for Crowley's Ridge with some of its highest
... [DOC] [TLE] Alluvial Landforms - Earth Online Media [PAR] Jun 5, 2012 ... Rivers that have reached base level develop broad valleys by erosion caused ...