Date of Award


Document Type


Degree Name

Master of Science (MS)



First Advisor

D.L. Halvorson


The archeology of the Knife River Indian Villages National Historic Site is being studied by the University of North Dakota Anthropology Department. The age of the near surface sediment and depositional history of Quaternary sediments are useful to archeologists involved in locating and interpreting the cultural resources of this area.

There are eight river terraces within a 300 square kilometre area surrounding the Knife River Indian Villages National Historic Site, near Stanton, North Dakota. , The terraces are former river floodplains that have been preserved above the present floodplain. The elevation above river level of the Pleistocene terraces are listed: Riverdale Terrace (67 to 9J metres), Sakakawea Terrace {51 to 61 metres), and Stanton Terrace (8 to·15 metres). There are three Holocene terraces: A terrace (6 to 8 metres), B1 terrace (l! to 6 metres), and B2 terrace (0 to 5 metres). The Pleistocene terraces can be identified because of the relatively flat land surface at similar elevations above river level. Relative age of the Pleistocene terraces increases with increased elevation above river level. The Holocene terraces were identified by the flat land surface, elevation above river level, and stratigraphy. Radiocarbon dates from twelve wood and charcoal samples found within Holocene alluvial deposits ranged in age from about 4000 BP to the present.

Eight lithostratigraphic units are present in the study area. Unit One is f1uvial sediment consisting of poorly lithified yellow, brown, gray and white sand, silt, silty clay, and clay. Unit One contains beds of lignite. Unit Two is a layer of glacial sediment consisting of grayish-brown, pebbly clay-loam. Unit Three is fluvial, glacio-fluvial and beach deposits consisting of gray to reddish-brown, silty sand, sat and gravel. Unit Four is lake sediment consisting of flat-bedded light-brown to grayish-brown fine-grained sand, silt, and clay. Unit Five is eolion, light-brown to very dark-brown, vaguely bedded, well sorted, very fine-grained, sandy silt. Unit Six is windblown sediment consisting of light-yellowish-brown to very dark-brown well sorted fine- to medium-grained sand. Unit Seven is alluvial sediment consisting of light-yellowish-brown interbedded clay, silt and sand. Unit One is part of the Paleocene Age Bullion Creek an, Sentinel Butte Formations. Units Two, Three and Four are part of th« Pleistocene Age Coleharbor Formation. Units Five, Six and Seven are of Late Wisconsinan to Holocene Age and are part of the Oahe Formation.

Climatic changes since the retreat of the Late Wisconsinan glacier~ probably controlled deposition and erosion of the Oahe Formation and Holocene terraces. During cool, moist climates, soils developed and rivers incised their floodplains. During warm, dry climates, soil developnent decreased and river floodplains aggraded. Fran about 13 000 BP to 8500 BP a cool, moist climate caused rivers to incise and soil developnent to increase forming the dark colored Aggie Brown Member of the Oahe Formation. A warmer, drier climate from about 8500 BP to 4500 BP caused river floodplains to aggrade forming the lower A terrace alluvial fill. The light colored Pick City Member of the Oahe Formation was deposited. Since 4500 BP the climate has fluctuated from cool, moist conditions to warm, dry conditions. The A, Bl and B2 terraces were formed and the Riverdale Member of the Oahe Formation, composed of alternating layers of light colored and dark colored sediment, was deposited.

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