The BGS Lexicon of Named Rock Units — Result Details

Tissington Volcanic Member

Computer Code: TIVO Preferred Map Code: TiV
Status Code: Full
Age range: Brigantian Substage (CX) — Brigantian Substage (CX)
Lithological Description: Mainly a hyaloclastite, composed of highly amygdaloidal and partly carbonated basaltic rock fragments. Minor basaltic lavas also occur.
Definition of Lower Boundary: Taken at the first bed of slumped, laminated dark grey to grey dolomitised limestone containing angular lapilli of amygdaloidal basalt lava (in Lees Farm Borehole, SK 15 SE/12); depth 182.02m.
Definition of Upper Boundary: Taken at the last occurrence of calcitic igneous rock and mudstone, or of hyaloclastite. This is overlain by calcareous mudstones and thin limestones of the Widmerpool Formation (in Tissington 1 and 2 Boreholes, SK 15 SE/13 and 14).
Thickness: Up to 44m recorded.
Geographical Limits: The principal outcrop extends from a locality 250m NW of Pethills (SK 207 493) to about 100m SE of Crakelow Farm (SK 177 535).
Parent Unit: Widmerpool Formation (WDF)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Reference Section  Near Woodeaves Farm. 
Partial Type Section  Lees Farm Borehole (SK 15 SE/12), between 182.02 m. - 152.46 m. 
Reference Section  Tissington No. 2 Borehole (SK 15 SE/14) between 26.4 m. - 42.8 m. 
Chisholm, J I, Charsley, T J and Aitkenhead, N. 1988. Geology of the country around Ashbourne and Cheadle. Memoir of the British Geological Survey, Sheet 124 (England and Wales). 
1:50K maps on which the lithostratigraphical unit is found, and map code used: