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Holocene surficial deposits

Unconsolidated deposits associated with modern fluvial systems. This unit consists primarily of fine-grained, well-sorted sediment on alluvial plains, but also includes gravelly channel, terrace, and alluvial fan deposits on middle and upper piedmonts. (0-10 ka)
State Arizona
Name Holocene surficial deposits
Geologic age Holocene
Comments Associated with modern fluvial systems
Primary rock type sand
Secondary rock type gravel
Other rock types mud; silt
Lithologic constituents
Major
Unconsolidated > Coarse-detrital > Sand (Alluvial)
Minor
Unconsolidated > Coarse-detrital > Gravel (Alluvial)
Unconsolidated > Coarse-detrital > Gravel (Fluvial)
Unconsolidated > Coarse-detrital > Gravel (Terrace, stream)
Incidental
Unconsolidated > Coarse-detrital > Gravel (Colluvial)
Unconsolidated > Coarse-detrital > Gravel (Mass wasting)
Unconsolidated > Coarse-detrital > Gravel (Landslide)
Unconsolidated > Coarse-detrital > Sand (Colluvial)
Unconsolidated > Coarse-detrital > Sand (Eolian)
Unconsolidated > Coarse-detrital > Sand (Fluvial)
Unconsolidated > Coarse-detrital > Sand (Terrace, stream)
Unconsolidated > Coarse-detrital > Sand (Lacustrine)
Unconsolidated > Fine-detrital > Silt (Alluvial)
Unconsolidated > Fine-detrital > Silt (Fluvial)
Unconsolidated > Fine-detrital > Silt (Terrace, stream)
Unconsolidated > Fine-detrital > Silt (Lacustrine)
Unconsolidated > Fine-detrital > Silt (Eolian)
Unconsolidated > Fine-detrital > Clay (Fluvial)
Unconsolidated > Fine-detrital > Clay (Alluvial)
Unconsolidated > Fine-detrital > Clay (Terrace, stream)
Unconsolidated > Fine-detrital > Clay (Lacustrine)
Map references
Richard, S. M., Reynolds, S.J., Spencer, J. E., and Pearthree, P. A., 2000, Geologic Map of Arizona: Arizona Geological Survey Map 35, 1 sheet, scale 1:1,000,000.
Unit references
Richard, S. M., Reynolds, S.J., Spencer, J. E., and Pearthree, P. A., 2000, Geologic Map of Arizona: Arizona Geological Survey Map 35, 1 sheet, scale 1:1,000,000.
Counties Apache - Cochise - Coconino - Gila - Graham - Greenlee - La Paz - Maricopa - Mohave - Navajo - Pima - Pinal - Yavapai - Yuma