DOI: 10.1016/j.quascirev.2014.05.029
Scopus记录号: 2-s2.0-84902986374
论文题名: Rock-magnetic signature of precipitation and extreme runoff events in south-eastern Patagonia since 51,200calBP from the sediments of Laguna Potrok Aike
作者: Lisé-Pronovost A. ; St-Onge G. ; Gogorza C. ; Jouve G. ; Francus P. ; Zolitschka B.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2014
卷: 98 起始页码: 110
结束页码: 125
语种: 英语
英文关键词: Gyroremanent magnetization
; Lacustrine sediment
; Laguna Potrok Aike
; Mass movement deposit
; Paleoenvironment
; Rock magnetism
Scopus关键词: Catchments
; Demagnetization
; Deposits
; Geomagnetism
; Iron
; Lakes
; Magnetization
; Runoff
; Sedimentology
; Sediments
; Stratigraphy
; Lacustrine sediments
; Laguna potrok aike
; Mass movement
; Paleo-environment
; Rock magnetism
; Sedimentary rocks
; facies
; geochronology
; hematite
; isotherm
; lacustrine deposit
; last glaciation
; magnetization
; paleoenvironment
; precipitation (climatology)
; runoff
; sedimentary sequence
; sulfide
; Argentina
; Laguna Potrok Aike
; Patagonia
; Santa Cruz [Argentina]
英文摘要: A 106-m long sediment sequence from the maar lake Laguna Potrok Aike in southern Patagonia was recovered in the framework of the International Continental Scientific Drilling Program (ICDP) Potrok Aike maar lake Sediment Archive Drilling prOject (PASADO). About half of the sedimentary sequence is composed of mass movement deposits (MMDs) and the event-corrected record reaches back to 51,200calBP. Here we present a high-resolution rock-magnetic study revealing two sedimentary facies associated with MMDs and characterized by two different types of spurious gyroremanent magnetization (GRM) acquired during static alternating field demagnetization. The first rock-magnetic signature is detected in MMDs composed of reworked sand and tephra material. The signature consists of GRM acquired during demagnetization of the natural remanent magnetization (NRM) and other rock-magnetic properties typical of iron sulfides such as greigite. We interpret these intervals as authigenic formation of iron sulfides in suboxic conditions within the MMD. The second rock-magnetic signature consists of a series of 10 short intervals located on the top of MMDs characterized by GRM acquisition during demagnetization of the isothermal remanent magnetization (IRM). Based on geological, limnological, stratigraphic and climatic evidence these layers are interpreted as reflecting pedogenic hematite and/or goethite brought to the lake by runoff events related to precipitation and permafrost melt. The pedogenic iron minerals mobilized from the catchment most likely settled out of suspension on top of MMDs after a rapid remobilization event. The series of runoff events corresponds to periods of increased lacustrine productivity in Laguna Potrok Aike and are coeval within the limit of the chronology to warm periods of the Last Glacial as recorded in Antarctica, the deglaciation in the mid-latitudes of the Southern Hemisphere and enhanced precipitation during the Early Holocene in southeastern Patagonia. © 2014 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60207
Appears in Collections: 过去全球变化的重建
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作者单位: Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, Rimouski, Canada; GEOTOP Research Center, Montréal, Canada; Centro de Invest.s en Física e Ingeniería del Centro de la Provincia de Buenos Aires, Tandil, Argentina; Centre Eau, Terre et Environnement, Institut National de la Recherche Scientifique, Québec, QC, Canada; GEOPOLAR, Institute of Geography, University of Bremen, Bremen, Germany
Recommended Citation:
Lisé-Pronovost A.,St-Onge G.,Gogorza C.,et al. Rock-magnetic signature of precipitation and extreme runoff events in south-eastern Patagonia since 51,200calBP from the sediments of Laguna Potrok Aike[J]. Quaternary Science Reviews,2014-01-01,98