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Mineral Resources > Online Spatial Data > Geology > by state > North Dakota Geology

Geologic units in Dickey county, North Dakota

Glacial Sediment- Glacial Sediment Draped Over Pre-existing Topography (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 4 % of this area

Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)

Lithology: clay or mud; silt; sand; gravel

Till, Ground Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin]) at surface, covers < 0.1 % of this area

Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by smooth, rolling terrain. Composite thickness of all Upper Wisconsin till may be up to 300 ft (91 m).

Lithology: clay or mud; silt; sand; gravel

Coleharbor Formation- River Sediment- Collapsed River Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 0.6 % of this area

Moderately well sorted cross-bedded sand and plane-bedded gravel, including sediment of melt-water and other rivers; as thick as 30 meters (100 feet). Faulted and contorted supraglacial sediment with hummocky topography.

Lithology: sand; gravel

Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 56 % of this area

Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)

Lithology: clay or mud; silt; sand; gravel

Till, Stagnation Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin]) at surface, covers 0.1 % of this area

Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by hummocky terrain with abundant sloughs resulting from stagnation of ice sheets. Composite thickness of all Upper Wisconsin till may be up to 300 ft (91 m).

Lithology: clay or mud; silt; sand; gravel

Till, Minor Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin]) at surface, covers < 0.1 % of this area

Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by elevated linear ridges including minor, washboard, or recessional moraines. Composite thicknessof all Upper Wisconsin till may be up to 300 ft (91 m).

Lithology: clay or mud; silt; sand; gravel

Till, End Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin]) at surface, covers < 0.1 % of this area

Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by elevated linear ridges with hummocky terrain locally at former ice sheet margins. Composite thicknessof all Upper Wisconsin till may be up to 300 ft (91 m).

Lithology: clay or mud; silt; sand; gravel

Eolian Deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

(loess and sand dune) Silt to medium-grained sand. Deposited as sand sheets and barchan, linear, and dome-like dunes and as veneer on uplands. Thickness up to 300 ft (91m).

Lithology: silt; sand

Coleharbor Formation- River Sediment- Uncollapsed River Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 0.7 % of this area

Moderately well sorted cross-bedded sand and plane-bedded gravel, including sediment of melt-water and other rivers; as thick as 30 meters (100 feet). Flat-bedded sediment of gently sloping plains and terraces, commonly with braided-channel scars.

Lithology: sand; gravel

Glacial Sediment- Glacial Sediment on Thrust Masses (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 0.8 % of this area

Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)

Lithology: clay or mud; silt; sand; gravel

Oahe Formation- River Sediment (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 7 % of this area

Dark, obscurely bedded clay and silt (overbank sediment); generally overlying cross-bedded sand (channel sediment); as thick as ten meters (30 feet); on flood plains of modern streams.

Lithology: clay or mud; silt; sand

Outwash, Undifferentiated (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin]) at surface, covers < 0.1 % of this area

Heterogeneous sand and gravel, with minor clay and silt. Deposits of glaciofluvial orgin including outwash plains, kame terraces, and other undifferentiated deposits. Thickness up to 30 ft (9m).

Lithology: sand; gravel; clay or mud; silt

Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 7 % of this area

Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)

Lithology: clay or mud; silt; sand; gravel

Oahe Formation- Windblown Sand (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 0.2 % of this area

Well-sorted, medium sand with obscure bedding; poorly developed palesols common; as thick as 10 meters (30 feet); knobby topography consisting of inactive transverses or longitudinal dunes nearly obliterated by more recent blowouts.

Lithology: sand

Sand of the Oahe and Older Formations, Undivided (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene(?) Holocene) at surface, covers 6 % of this area

Windblown sand of the Oahe Formation, as thick as 3 meters (10 feet), and sand of older formations with an undulating wind-scoured surface.

Lithology: sand

Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 4 % of this area

Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)

Lithology: clay or mud; silt; sand; gravel

Alluvium (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

Clay to boulder-size clasts with locally abundant organic material. Thickness up to 75 ft (23m).

Lithology: clay or mud; silt; sand; gravel

Outwash, Collapsed (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin]) at surface, covers < 0.1 % of this area

Heterogeneous sand and gravel of glaciofluvial orgin. Deposited as outwash sediments that collapsed due to melting of buried ice. Thickness up to 90 ft (27m).

Lithology: sand; gravel

Coleharbor Formation- Offshore Sediment- Ice-Walled Lake Sediment or Collapsed Supraglacial-Lake Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 0.2 % of this area

Laminated silt and clay of glacier-dammed lakes; as thick as 60 meters (200 feet). Flat-bedded sediment elevated above surrounding area or floded sediment with hummocky topography.

Lithology: silt; clay or mud

Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 8 % of this area

Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)

Lithology: clay or mud; silt; sand; gravel

Glacial Sediment- Collapsed/Draped Transition Sediments (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 2 % of this area

Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)

Lithology: clay or mud; silt; sand; gravel

Lacustrine Sediments (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin]) at surface, covers < 0.1 % of this area

Glaciolacustrine clay and silt with minor sand and gravel. Forms flat, low-lying terrain. Includes deposits from Glacial Lake Dakota and Glacial Lake Agassiz. Thickness up to 60 ft (18m).

Lithology: clay or mud; silt; sand; gravel

Coleharbor Formation- Offshore Sediment- Proglacial Lake Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 1 % of this area

Laminated silt and clay of glacier-dammed lakes; as thick as 60 meters (200 feet). Flat-bedded sediment of low-lying plains

Lithology: silt; clay or mud

Glacial Sediment- Slopwash-Eroded Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 1 % of this area

Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)

Lithology: clay or mud; silt; sand; gravel