Hamps and Manifold Valleys: SK 100540
A range of features of special geological interest cover almost the whole area of this complex site. The features of water-worn limestone (karst) extend throughout the river valleys; there are classical rock exposures showing the way in which the limestone was formed; an example of re-distributed limestone scree from the postglacial period and caves with important fossil animal remains.
The site includes much of the limestone valleys of the Manifold and Hamps rivers where they are entrenched into the Peak District Carboniferous Limestone Plateau. Sinks are common and the site is an excellent example of partial underground capture of surface rivers in a karst region. An isolated part of the cave site which covers the risings lies adjacent to Ilam village. Contrasting extents of river capture are demonstrated by the Hamps, which nearly always sinks underground, and the Manifold which sinks at various locations depending on stage but in flood maintains a surface course right across the limestone outcrop.
To the north-east of the site, the Wetton-Gratton area extending up to Beresford Dale, shows extensive sections through much of the Dinantian stage of the Carboniferous with superb sedimentological features and rich faunas in both basinal and shelf environments. The locality covers a range of reef types and depositional environments of different ages, including apron reefs of Asbian age on the shelf margin and reef knolls in the basin. The origin of the reef knolls, in particular, is still poorly understood. The site offers an outstanding carbonate research locality on the edge of the Peak District limestone plateau, unrivalled in the complexity of its facies relationships in this complex area of shelf, reef and basinal limestone deposition.
Ecton Quarry is a site of significant geomorphological interest which provides a rare and permanent exposure through cemented and stratified limestone talus. Formed during the Late Pleistocene, the talus comprises stratified layers of coarse angular detritus and finer, more weathered material. It has been cemented by deposition of calcite in the voids between particles of debris. The stratification may reflect seasonal or climatic changes in groundwater conditions, or possibly changes in debris-supply conditions.
Elderbush Cave has yielded Pleistocene age faunas from three main horizons. The two younger horizons of Devensian glacial age contain arctic lemming, Norway lemming, various voles, bears, lion, spotted hyaena, horse, woolly rhino, reindeer and other mammals. A significant amount of these deposits remain in situ, making this locality one with considerable research potential for Pleistocene mammalian studies. There are complementary deposits at Seven Ways Cave, which have yielded a Devensian cold fauna including reindeer, and at Thor's Fissure which has an important Devensian 'Late Glacial' fauna with reindeer and small vertebrates associated with Upper Palaeolithic artefacts.
Ossoms Cave, although small, is of considerable interest for its occupation during late Pleistocene times by both roosting birds and human hunters. Detailed excavation of well-stratified late glacial Devensian deposits has yielded an extensive fauna, including small mammals and birds, which have been radio-carbon dated to 10,590 years Before Present.
Source: SSSI citation, English Nature