Stony Middleton Dale SSSI - Carlswark Cavern – Resurgence entrance
The cliffs on the north side of Stoney Middleton Dale contain numerous caves, ranging from short segments of phreatic tube
only a few metres long up to the Carlswark Cavern / Merlin Mine system, with more than 3km of surveyed passage. The area
is important since it demonstrates, better than any other area in the Peak District, a sequence of cave levels developed
successively in response to stages in the lowering of the valley floor. These levels can be correlated with successive levels in
other catchment areas such as Bradwell and Castleton, and dated speleothems and sediments then allow the development of an
absolute time scale for the evolution of the major gorges and dry valley networks of the limestone area (Beck, 1980).
The highest levels are represented by isolated fragments of vadose cave such as Cucklet Church Cave, at 240m OD, while the
present active resurgence (now only active in flood conditions due to capture by mine drainage) lies at 174m OD. Four distinct
levels were recognised by Beck (1980) as follows:
1. The First Remnant Complex (Ivy Green Cave, Keyhole Cave, Bossen Hole and high level passages in Carlswark Cavern).
2. The Second Remnant Complex (represented only by short segments in the Dynamite Series of Carlswark Cavern).
3. The Carlswark Complex (including most of Carlswark Cavern, Streaks Pot, Yoga Cave, Lay-by Pot and many small
caves), the northwestern areas of which are still active.
4. The Lower Complex, seen only in the resurgence passages of Carlswark Cavern.
The clear distinction between levels results from the structure of the area between the swallets at the base of Eyam Edge
between Eyam and Swevic House, north of Foolow. The hydraulic gradient from sink to resurgence corresponds closely with
the strike of the limestones, so that each phase of valley floor lowering resulted in the abandonment of a large network of
conduits as the drainage was slowly captured by caves at lower horizons.
The caves are not large or spectacular, but there are many classic stretches of passage. Every small passage segment can be
regarded as part of an important overall picture.
Carlswark Cavern:
The majority of the phreatic passages in Carlswark Cavern and the lower parts of Merlin Mine are formed along the base of a
prominent fossil horizon, the Lower Shell Bed, and give the name to the most extensive phreatic network, the Carlswark
Complex. The western part of the network (the Merlin Streamway – John Smith’s Passage - the Lower Streamway) is still
active, but the streams have been captured by Moorwood Sough, further down-dip to the north. In flood conditions water
follows its natural route, and rises from the Resurgence Entrance, which is the outlet of phreatic passages at a lower horizon.
CAVE CONSERVATION MONITORING FORM -Carlswark Cavern - Resurgence entrance
Feature
number
on survey
Description of interest features.
E.g. Cave passage Morphology (CPM).
CSS – Cave Sediment Sequence
Are the
features
still
present?
Y/N
(Version 3 - Dec02)
Comments on the condition of the features
1
Resurgence Passage (CPM)– passage dry for
most of the year as a result of de-watering of
the cave by the driving of Moorwood Sough,
and now discharges water only under flood
conditions. It leads down to the Lower Sump,
which is almost permanently flooded.
e.g. Passage intact? If not – explain.
?evidence of water pollution (in active passages)
2a
Eyam Passage- (CPM). Relict phreatic tube
of the Carlswark Complex, the most extensive
level of the system. Eyam Passage has a
spectacular roof formed by solution of the
Lower Shell Bed, and also reveals excellent
examples of bedding plane anastomoses.
(As above)
2b
Eyam Passage- (CPM). (as 2a)
(As above)
3
Unnamed tube, east side of Eyam Passage.
(CSS) The sequence consisted of a sandy silt
overlying a thin stalagmite layer underlain by
well rounded pebbles of baryte and limestone
in a sandy matrix.
e.g. if unexcavated, is sequence disturbed or if
excavated are sections retained for future study? If
disturbed - explain.
4a
North West Passage (CSS)
(As above)
Similar sequence to 3.
4b
North West Passage (CSS)
(As above)
Similar sequence to 3.
5
Dynamite Series (CPM) - series of joint
controlled chambers connected by small
phreatic tubes intersecting segments of larger
passage belonging to the First and Second
Remnant complexes at the north end.
General comments on
conservation status of
the cave
Please indicate on map location of any
mineral deposits and any unauthorised
collection.
Name:
Contact details:
e.g. Passage intact? If not – explain.
?evidence of water pollution (in active passages)
(eg Heavily used cave, much carbide, pollution,
changes to drainage system, specimen collecting,
areas inaccessible due to rock fall etc)
Date of visit:
Telephone/Email:
For return details and advice please see http://thedca.org.uk/sssi-monitoring.
“Thank you for assisting in the conservation of this cave.”
Carlswark Cavern, Stoney Middleton.
NGR: 2207 7580
LENGTH: 3243m (10641ft)
ALTITUDE: 171.6m (563ft)
SOURCE:
MIDGLEY, 1983