The caves of Giggleswick Scar-examples of deglacial speleogenesis?

The prominent Giggleswick Scar at the South Craven Fault extremity of the Carboniferous limestone of the Askrigg Block in North Yorkshire, UK, contains relict phreatic caves whose speleogenesis is enigmatic. This paper examines the local geomorphological evidence and proposes that some, but not necessarily all, karst features along and above the Scar formed after the Last Glacial Maximum. Building on a previous deglacial model for the Yorkshire Dales, it is hypothesized that inception fractures and bedding plane partings were created during isostatic uplift. These were then likely enlarged by dissolution in cold unsaturated meltwater beneath a local flowing deglacial ice-dammed lake that formed initially at an altitude of c.300m, with a catchment area of c. 2km2. Rising cupolas outside Gully Cave were probably formed at c. 18ka BP by meltwater flowing up into a moulin within the ice, which continued to be cold-based farther south. As the ice-sheet slowly downwasted, the surface of the lake would have widened and lowered past the newly-formed cave entrances. Some of these were probably enlarged by freeze-thaw and lake-ice push and pull processes. Indeed, the heights of some enlarged entrances correspond to proposed stabilizing lake overflow levels. It is also assumed that the local ice-dammed lake coalesced with the main Settle glacial lake, until a jokulhlaup created a ravine above pre-existing glacial scoops in the limestone cliff. Thereafter, the lake split into two parts on each side of Buckhaw Brow, whilst still inundating the lower caves. If this hypothesis applies, it has wider implications for cave speleogenesis and sedimentation in the Yorkshire Dales.