Sediment dynamics in the Castleton karst, Derbyshire, UK

Chemical and mineralogical data are presented for a suite of 59 sediment sa mples collected from the P8 and Speedwell cave systems (and mineralogical d ata are presented for a further six surface sediments) in the Castleton kar st catchment, Derbyshire, England. Sediments are grouped according to age a nd depositional environment and these groups show distinctive mineralogical and chemical characteristics. Clay mineralogy is effective at distinguishi ng different sediment sources for ancient and modem sediments which are der ived from pre-Devensian tills and Devensian solifluction deposits, respecti vely. Major element chemistry reflects these differences in clay mineral co ntent, while trace elements demonstrate the importance of abrasion of ore m inerals in conduits in the aquifer which follow mineral veins, even under n atural, premining conditions. Clay minerals are confirmed as the host for u ranium in uranium-rich ancient sediments. Consideration of organic carbon a nd hydrogen concentrations shows that plant material is the dominant source of organic material in the modern sediments. Copyright (C) 1999 John Wiley & Sons, Ltd.