A guide to Spring Cove
Spring Cove is geographically located on the North Somerset coastline just a few hundred feet to the north-east from the mainland end of Birnbeck Pier.
Here it is seen in the natural surrounding environment as viewed looking down from the top of Birkett Road, W-s-M:
(Image by 'Jaggery' - released under a Creative Commons Licence - see this link)
The area is notified as part of a Site of Special Scientific Interest (SSRI) in two regards.
The first is insofar as it falls within the Severn Estuary SSRI.
The second is that it is a site where a particular geological rock formation can be seen - namely volcanic rock from the Dinantian times.
FROM ENGLISH NATURE:
COUNTY: AVON SITE NAME: SPRING COVE CLIFFS
Status: Site of Special Scientific Interest (SSSI) notified under Section 28 of the Wildlife and Countryside Act 1981 (as amended).
Local Planning Authority: AVON COUNTY COUNCIL, Woodspring District Council
National Grid Reference: ST 310625 Area: 2.0 (ha.) 4.9 (ac.)
Ordnance Survey Sheet 1:50,000: 182 1:10,000: ST 36 SW
Date Notified (Under 1949 Act): 1952 Date of Last Revision: 1974
Date Notified (Under 1981 Act): 1986 Date of Last Revision: 1991
A Geological Conservation Review site.
Part of this site lies within the Severn Estuary Site of Special Scientific Interest.
Description and Reasons for Notification:
Spring Cove Cliffs are of geological importance because of the stratigraphic and igneous features which are displayed.
The stratigraphical sequence of rock is part of the Burrington Oolite Group (of Arundian age) and provides evidence of localised, penecontemporaneous volcanic activity in mid-Dinantian times. The sections in the Carboniferous Limestone are unusual for the region; they include carbonate and clastic sediments together with basaltic lavas and agglomerates.
Spring Cove Cliffs is a classic locality for the study of volcanic rocks of Early Carboniferous age in southern England. The sequence of Dinantian volcanic rocks, about 18 metres thick, is significant for its southerly position within the Dinantian sequences, lying to the south of the St George’s Land landmass, and also because of the submarine character of the lavas and their intimate relationship with adjacent carbonate sediments. The lava, which is pillowed in places, is believed to have been extruded upon a sloping seafloor. As it flowed downslope it autobrecciated and incorporated blocks of limestone from the underlying substrate.
WESTON-SUPER-MARE VOLCANICS FIELD TRIP - 18th MAY 2008 with Dave Green & Alan Holiday - Journal of the Bath Geological Society, No. 28, 2008
Evidently, it is the black and brown-coloured rock that is of special interest. Much more of this geology can nowadays be seen further slightly along the coastline, below the Toll Road towards Kewstoke, where significant erosion has taken place due to strong tidal action over recent years.
The following is a crop of a screenshot taken from the NSC website. It clearly shows the notified area of the Spring Cove SSSI.
© NSC/Ordnance Survey
Here are a set of photographs of the rock formations at Spring Cove, many of which look quite unremarkable to the untrained eye. Note the person in the third picture, a human being is needed here to give a sense of scale to the place!
The following are a couple of pictures of a similar formation of pillowed volcanic rock in the Fife (Scotland) area. With these in mind, it is fairly easy to spot what is of importance here at Spring Cove. Plainly, the rock at SC is of the same origin, but is not so automatically distinguishable as being something out of the ordinary.
(These last two images taken from: Pillows at Kinghorn, by 'Claxons'. There is a good description of the process of the formation of this type of rock there, along with this link to a YouTube video of this actually happening.)