DOI: 10.1016/j.quascirev.2014.09.005
Scopus记录号: 2-s2.0-84909580967
论文题名: Noble gases in the sediments of Lake Van - solute transport and palaeoenvironmental reconstruction
作者: Tomonaga Y. ; Brennwald M.S. ; Meydan A.F. ; Kipfer R.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2014
卷: 104 起始页码: 117
结束页码: 126
语种: 英语
英文关键词: Deep drilling
; ICDP
; Palaeosalinity
; PaleoVan
; Terrestrial He emission
Scopus关键词: Deep drilling
; ICDP
; Lake vans
; Palaeo-salinity
; Palaeoenvironmental reconstruction
; PaleoVan
; continental crust
; deep drilling
; helium
; lacustrine deposit
; lithology
; mineral
; noble gas
; paleoenvironment
; paleosalinity
; porewater
; reconstruction
; sediment analysis
; sediment chemistry
; solute transport
; Lake Van
; Turkey
英文摘要: Sediment samples acquired in 2010 from the long cores of the International Continental Scientific Drilling Program (ICDP) PaleoVan drilling project on Lake Van for noble-gas analysis in the pore water allow determination of the local terrestrial He-gradient as a function of depth within a sediment column of more than 200m. These measurements yield first insights into the physical transport mechanisms of terrigenic He through the uppermost part of unconsolidated lacustrine sediments overlying the continental crust.In line with our previous work on the spatial distribution of the terrigenic He release into Lake Van, we identify a high He concentration gradient in the uppermost 10m of the sediment column. The He concentration gradient decreases below this depth down to approx. 160. m following in general the expectations of the modelling of radiogenic He production and transport in a sediment column with homogeneous fluid transport properties. Overall the in-situ radiogenic He production due to the decay of U and Th in the mineral phases of the sediments accounts for about 80% of the He accumulation. At approx. 190. m we observe a very high He concentration immediately below a large lithological unit characterised by strong deformations. We speculate that this local enrichment is the result of the lower effective diffusivities in the pore space that relate to the abrupt depositional history of this deformed unit. This particular lithological unit seems to act as a barrier that limits the transport of solutes in the pore space and hence might "trap" information on the past geochemical conditions in the pore water of Lake Van.The dissolved concentrations of atmospheric noble gases in the pore waters of the ICDP PaleoVan cores are used to geochemically reconstruct salinity on the time scale of 0-55kaBP. Higher salinities in the pore water at a depth of about 20m suggest a significantly lower lake level of Lake Van in the past. © 2014 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60125
Appears in Collections: 过去全球变化的重建
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作者单位: Eawag, Swiss Federal Institute of Aquatic Science and Technology, Water Resources and Drinking Water, Duebendorf, Switzerland; Department of Geological Engineering, Yuzuncu Yil University, Van, Turkey; Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology, Zurich, Switzerland; Institute of Geochemistry and Petrology, Swiss Federal Institute of Technology, Zurich, Switzerland
Recommended Citation:
Tomonaga Y.,Brennwald M.S.,Meydan A.F.,et al. Noble gases in the sediments of Lake Van - solute transport and palaeoenvironmental reconstruction[J]. Quaternary Science Reviews,2014-01-01,104