SITE
Name: Western King
Parish/Area: Stonehouse
Local Authority: Plymouth
National Grid Ref: SX 462 533
OS Sheets: 1:50K, 201, 1:10K, SX45 SE
Locality Description: This site lies within Plymouth on the promontory of Western King
Point.
Nature and Status of Site: Fossiliferous limestone in the foreshore and cliff exposures
around Western King Point. The area is a Site of Special Scientific Interest (SSSI).
Summary of Geological / Geomorphological Interests: This site exposes a complex
series of grey and pink Devonian limestones with discontinuous beds of red shale, of
late Frasnian to early Famennian age, which comprises the youngest limestones of the
Plymouth Limestone Group. These were deposited in a reef environment. They contain
an important fauna of microfossils, known as conodonts, which are used to subdivide the
rock sequence and relate it to comparable sequences elsewhere. Western King is also
of considerable historical interest since some of the earliest studies on British fossil
corals of Devonian age were carried out here.
Safety Considerations: No major hazards, although coastal safety measures should be
adopted and hard hats used around any cliff face. Observe on-site restrictions and
notices.
Educational Age Groups: Secondary, College/6th Form, University.
Parking and Access: A public amenity area lies immediately above the cliffs and
access to the exposure is unlimited. There is roadside parking available and a car park
adjacent to the eastern end of the site. Additionally there is a regular bus service from
Plymouth (Royal Parade) to Edgecumbe Street and the site can be accessed on foot
along Durnford Street from this point. For timetable details, visit www.traveline.org.uk.
The exposures should not be hammered and fossils should be left for others to see.
______________________________________________________________________
References
CHANDLER, P. and McCALL, G.J.H. 1985. Stratigraphy and structure of the PlymouthPlymstock area: a preliminary review. Proc. Ussher Soc. 6, 253-257.
HOBSON, D. M. 1978. The Plymouth area. Geologist’s Association Guide No. 38.
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), 143pp
ORCHARD, M. J. 1974. Famennian Conodonts and Cavity Infills in the Plymouth
Limestone (S. Devon). Proc. Ussher Soc., 3, 49-54.
Educational Register of Geological Sites
ORCHARD M. J. 1978a. Plymouth Limestone in Scrutton C. T. (Ed). A Field Guide to
Selected Areas of the Devonian of Southwest England. 53-56 The Palaeontological
Assoc.
ORCHARD M. J. 1978). The Conodont Biostratigraphy of the Devonian Plymouth
Limestone, South Devon. Palaeontology, 21, 907-955.
TAYLOR, P.W. 1951. The Plymouth Limestone: and the Devonian tetracorals of the
Plymouth Limestone. Trans. Roy. Geol. Soc. Cornwall, 18, 146-214.
USSHER, W.A.E. and FLETT, J.H. 1907. The geology of the country around Plymouth
and Liskeard (Sheet 348). Memoirs of the Geological Survey, England and Wales,
156pp
Detailed Geology: The rocks exposed at this site comprise of steeply dipping (60°S),
irregularly bedded grey and pink limestones with discontinuous beds of red shale. Corals
and stromatoporoids in a matrix of crinoidal debris dominate the fauna. The conodont
fauna indicates the Lower assymetricus Zone and the base of the Ancyrognathus
triangularis Zone, i.e. mid to late Frasnian. The youngest conodont fauna taken from the
Plymouth Limestone Group was found in the red shales and was generally indicative of
the upper Palmatolepis triangularis Zone. The limestones, with the shales, are
considered to be deposited in a fore-reef environment. Western King is also unique in
exhibiting cavities within the limestone, which have been infilled by pink, red and grey
laminated limestones. These have been interpreted as having been filled
contemporaneously with the formation of the cavities. It is likely that deposition was
interrupted and a period of emergence occurred where dissolution took place forming a
complex of inter-connected pockets and cavities. This dissolution and subsequent
infilling took place because of subsidence of the coral and stromatoporoid reefs, which
brought about the deposition of red shales, and later the thick sequence of purple green
shales which succeed the Plymouth Limestone Group.
______________________________________________________________________
Suggested Questions
1. Draw, label and identify the various different rock types, along with their physical
characteristics.
2. The limestones contain numerous fossils. Draw and label two different types.
3. Noting that some of the beds do not extend the whole length of the exposure,
suggest a mode of deposition, in which this formation could have developed.
Educational Register of Geological Sites
LOCATION PLAN
WESTERN KING, SSSI
STONEHOUSE, PLYMOUTH
National Grid Ref: SX 462 533
© Crown copyright. All rights reserved. Devon County Council Licence No. 100019783 2008
Scale 1: 35,000
Site Locality
Located along Durnford
Street from junction 4 on
the A374
Parking and Access
• Limited parking and car park adjacent to the eastern end of
the site. From here, follow path which explores the cliff
section and amenity grassland and scrub.
• Bus services operating in Plymouth to nearby Edgecumbe
Street.
• Observe on-site restrictions and notices.
Educational Register of Geological Sites
SITE PLAN
WESTERN KING
STONEHOUSE, PLYMOUTH
National Grid Ref: SX 462 533
© Crown copyright. All rights reserved. Devon County Council Licence No. 100019783 2008
Scale 1: 5,000
Approx. SSSI Boundary
Main Points of Interest:
• Cliff and foreshore exposures showing a complex series of
Devonian limestones, deposited in a marine reef environment
• Contains an important fauna of microfossils known as conodonts,
which are used to subdivide the rock sequence and relate it to
comparable sequences elsewhere.
Educational Register of Geological Sites
© Bob Thomas
WESTERN KING
Bedding plane surface in Devonian limestone near the Artillery House at Western
King. The large pale masses are stromatoporoids, a type of coralline sponge often
dominating Devonian reef communities.
General view of the coastal exposures of Devonian limestones at Western King
Educational Register of Geological Sites