The hydrochemical response of cave drip waters to sub-annual and inter-annual climate variability, Wombeyan Caves, SE Australia

摘要: Abstract A thorough understanding of cave seepage waters is necessary to interpret geochemical variations in speleothem calcite terms changing surface climatic conditions at a particular site. Here we present the hydrochemistry ten drip from karst system SE Australia based on up 5.5 years monitoring. Discharge was continuously measured six sites and manually other sites. Dripwater samples were analysed for pH, electrical conductivity, cations anions all monthly or more frequent intervals. Each possesses unique chemistry, not responded antecedent short-term hydrological variations. For example, hydrochemical behaviour three adjacent drips bedrock depth 45 m completely different that shallower sites, apparently un-related hydrology throughout investigation. Based modelled precipitation vectors, prior demonstrated several but can only be linked directly changes recharge shallowest At extremely low flow, shallow accessed high Mg, Sr Ba source, thought overlying soil. High-frequency sample collection allows calculation predicted Mg/Ca Sr/Ca values, highlighting with greatest potential record high-resolution palaeohydrological records are those situated depth. Longer temporal-resolution may recorded deeper longer-term monitoring required identify probable time scales. Inherent non-linearities, dissolution secondary pore spaces aquifer, source trace elements, presence multiple reservoirs confirm need use speleothems multi-proxy approach gain accurate this