. Bulletin of the Natural Histort Museum. Geology series. . Fig. 2 Macrophotograph of whole thin section of sample I (cf. Fig. 1). Shown here are interbedded beds of elutriated silts (Si) and clay (C). Width of photo is cm. 1974; van Vliet-Lanoe, 1985, 1986). Extreme modification by freezing and thawing results in the fragmentation and chaotic mixing of the beds and link capping features, and infilling with impure clay and silt (Macphail, 1999) (Fig. 4). Biological activity is also recorded at Gough's Cave, forming channels and vughs through likely rooting and faunal burrowing. Finally, in
. Bulletin of the Natural Histort Museum. Geology series. . Fig. 2 Macrophotograph of whole thin section of sample I (cf. Fig. 1). Shown here are interbedded beds of elutriated silts (Si) and clay (C). Width of photo is cm. 1974; van Vliet-Lanoe, 1985, 1986). Extreme modification by freezing and thawing results in the fragmentation and chaotic mixing of the beds and link capping features, and infilling with impure clay and silt (Macphail, 1999) (Fig. 4). Biological activity is also recorded at Gough's Cave, forming channels and vughs through likely rooting and faunal burrowing. Finally, in this sequence many of these voids have been coated with dusty clay that implies renewed fluid transport vertically through the sediments (see below). Sand Hole (Pleistocene to earliest Holocene) Here the sequence commences with the deposition of cave muds (sample C) that accumulated in the base of the Sand Hole. These muds are composed of clay with clasts of redeposited clay (Fig. 5) and accumulated under conditions of low energy ponding. These deposits have reticulate b-fabrics induced by minor shrinking and swelling that reflect alternating periods of wetting and drying. It is possible that these muds are the finest deposits within the cave system, recording the end member of the upward fining sequence present in the main chamber. It is likely that this red clay owes its ultimate origin to the weathering of the Carboniferous Limestone, and is a form of transported Beta B clay (Duchaufour, 1977). In the Sand Hole, the sequence continues with the 'Laminated Stalagmite' and the 'Frog Earth' (Figs 6, 7). The laminated stalag- mite is composed of cryoclastically produced fallen limestone clasts and clay beds, which are both partially cemented by micrite originat- ing from drip. These deposits are succeeded by muds containing large numbers of frog bones that appear to be typical of early Holocene faunas (Currant, NHM, pers. comm.).. Please note that these images are extracted from
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