Computer Code: |
LCW |
Preferred Map Code: |
LCw |
Status Code: |
Pending Upgrade |
Age range: |
Homerian Age (SH)
— Homerian Age (SH) |
Lithological Description: |
[Obsolete: use BKR] The type area west of Windermere consists of a sequence of thickly bedded, fine-grained sandstones with subordinate, muddy siltstones; the thick sandstones wedge out east of Windermere and show a lateral transition into a facies with a characteristic "striped" appearance consisting of laminae (0.5 mm to 15 mm) and beds of coarse-grained silt in blue-grey silty mudstone of the Brathay Flags type lithology. |
Definition of Lower Boundary: |
Taken at base of lowest sandstone bed or of "striped facies" above the Brathay Flag Formation. |
Definition of Upper Boundary: |
Taken at the incoming of calcareous siltstones of the Middle Coldwell Beds. |
Thickness: |
c.200m at the type section, thins eastwards to less than 10m. |
Geographical Limits: |
Not defined. |
Parent Unit: |
none recorded or not applicable
|
Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Area |
North-west of Coldwell Quarry, Hawkshead, Cumbria, lower boundary well seen at High Cross Plantation, Sheet 38 (Ambleside). |
Reference(s): |
Marr, J E. 1878. On some well defined Life Zones in the lower part of the Silurian (Sedgwick) of the Lake District. Quarterly Journal of the Geological Society, Vol.34, p.871-885. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E039
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