DOI: 10.5194/hess-20-4625-2016
Scopus记录号: 2-s2.0-84996848137
论文题名: ENSO–cave drip water hydrochemical relationship: A 7-year dataset from south-eastern Australia
作者: Tadros C ; V ; , Treble P ; C ; , Baker A ; , Fairchild I ; , Hankin S ; , Roach R ; , Markowska M ; , McDonald J
刊名: Hydrology and Earth System Sciences
ISSN: 10275606
出版年: 2016
卷: 20, 期: 11 起始页码: 4625
结束页码: 4640
语种: 英语
Scopus关键词: Atmospheric pressure
; Carbon dioxide
; Climatology
; Dissolution
; Hydrochemistry
; Landforms
; Magnesium
; Nickel
; Precipitation (meteorology)
; Trace elements
; Geochemical composition
; Hydrochemical relationships
; Palaeoenvironmental reconstruction
; Prior calcite precipitations
; South-eastern Australia
; Stable oxygen isotopes
; Trace element concentrations
; Variable concentration
; Caves
英文摘要: Speleothems (cave deposits), used for palaeoenvironmental reconstructions, are deposited from cave drip water. Differentiating climate and karst processes within a drip-water signal is fundamental for the correct identification of palaeoenvironmental proxies and ultimately their interpretation within speleothem records. We investigate the potential use of trace element and stable oxygen-isotope (δ18O) variations in cave drip water as palaeorainfall proxies in an Australian alpine karst site. This paper presents the first extensive hydrochemical and δ18O dataset from Harrie Wood Cave, in the Snowy Mountains, south-eastern (SE) Australia. Using a 7-year long rainfall δ18O and drip-water Ca, Cl, Mg/Ca, Srg/gCa and δ18O datasets from three drip sites, we determined that the processes of mixing, dilution, flow path change, carbonate mineral dissolution and prior calcite precipitation (PCP) accounted for the observed variations in the drip-water geochemical composition. We identify that the three monitored drip sites are fed by fracture flow from a well-mixed epikarst storage reservoir, supplied by variable concentrations of dissolved ions from soil and bedrock dissolution. We constrained the influence of multiple processes and controls on drip-water composition in a region dominated by El Niño-Southern Oscillation (ENSO). During the El Niño and dry periods, enhanced PCP, a flow path change and dissolution due to increased soil CO2 production occurred in response to warmer than average temperatures in contrast to the La Niña phase, where dilution dominated and reduced PCP were observed. We present a conceptual model, illustrating the key processes impacting the drip-water chemistry. We identified a robust relationship between ENSO and drip-water trace element concentrations and propose that variations in speleothem Mg/Ca and Srg/Ca ratios may be interpreted to reflect palaeorainfall conditions. These findings inform palaeorainfall reconstruction from speleothems regionally and provide a basis for palaeoclimate studies globally, in regions where there is intermittent recharge variability. © 2016 Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/78686
Appears in Collections: 气候变化事实与影响
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作者单位: Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW, Australia; Connected Waters Initiative Research Centre, UNSW Australia, Kensington, NSW, Australia; School of Geography Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom; Birmingham Institute for Forest Research, University of Birmingham, Edgbaston, Birmingham, United Kingdom; NSW National Parks and Wildlife Service, Sydney, NSW, Australia; Environmental and Climate Change Research Group, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW, Australia
Recommended Citation:
Tadros C,V,, Treble P,et al. ENSO–cave drip water hydrochemical relationship: A 7-year dataset from south-eastern Australia[J]. Hydrology and Earth System Sciences,2016-01-01,20(11)