Computer Code: |
FLOW |
Preferred Map Code: |
notEntered |
Status Code: |
Full |
Age range: |
Quaternary Period (Q)
— Quaternary Period (Q) |
Lithological Description: |
Flows are landslides comprising a spatially continuous movement in which surfaces of shear are short-lived, closely spaced and not usually preserved. The distribution of velocities in the displacing mass resembles that in a viscous fluid whereby intergranular movements predominate over shear surface movements. Two broad categories of flows, ‘debris flow’ and ‘earth flow’, may be distinguished based on the predominance of coarse or fine material. A mudflow is a type of earth flow that is wet enough to flow rapidly and that contains at least 50% of sand-, silt- and clay-sized particles. Flows may be wet or dry and exhibit a wide range of movement rates from very slow (less than about 1.5 m/yr) to extremely rapid (more than 3 m/sec). |
Definition of Lower Boundary: |
none recorded or not applicable
|
Definition of Upper Boundary: |
none recorded or not applicable
|
Thickness: |
none recorded or not applicable
|
Geographical Limits: |
none recorded or not applicable
|
Parent Unit: |
Landslide deposits (SLIP)
|
Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
none recorded or not applicable |
Reference(s): |
McMillan, A A and Powell, J H. 1999. The classification of artificial (man made) ground and natural superficial deposits. British Geological Survey Research Report, RR/99/04. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
none recorded or not applicable |