The BGS Lexicon of Named Rock Units — Result Details

Bin Down Formation

Computer Code: BIN Preferred Map Code: Bin
Status Code: Full
Age range: Pragian Age (DP) — Pragian Age (DP)
Lithological Description: Grey slaty mudstone and quartzitic sandstone with interbedded, apparently extensively silicified basic lava and volcaniclastic rocks.
Definition of Lower Boundary: Faulted off against purple and green mudstone of the Whitsand Bay Formation.
Definition of Upper Boundary: Grey slaty mudstone passing up into purple and green slaty mudstone of the Whitsand Bay Formation.
Thickness: 300m
Geographical Limits: Geological sheet 348 (not mapped elsewhere).
Parent Unit: Dartmouth Group (DRTM)
Previous Name(s): Dartmouth Slates [Obsolete Name And Code] (DTMS)
Dartmouth Group (DRTM)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  Widegates Borehole SX25NE/1, 400m at 074 degrees from Bray House. 
Reference(s):
Sedgwick, A, 1852. On the slate rocks of Devon and Cornwall, Quarterly Journal of the Geological Society, Vol.8, 1-19. 
Leveridge B E, Holder, M T, Goode, A J J, Scrivener R C, Jones N S and Merriman, R J. 2002. Geology of the Plymouth and south-east Cornwall area. Memoir of the British Geological Survey, Sheet 348 (England and Wales). 
Ussher, W A E. 1891. The Devonian Rocks as described by De La Beche, etc. Transactions of the Royal Geological Society of Cornwall, Vol.II, 273-326. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E348