DOI: 10.1016/j.quascirev.2012.12.003
Scopus记录号: 2-s2.0-84872536828
论文题名: Submarine landforms in the fjords of southern Chile: Implications for glacimarine processes and sedimentation in a mild glacier-influenced environment
作者: Dowdeswell J.A. ; Vásquez M.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2013
卷: 64 起始页码: 1
结束页码: 19
语种: 英语
英文关键词: Chile
; Fjords
; Glacimarine sedimentation
; Glacimarine sediments
; Landform-assemblage model
; Retreat moraines
; Submarine landforms
; Turbidity-current channels
Scopus关键词: Chile
; Fjords
; Glacimarine sediment
; Retreat moraines
; Submarine landforms
; Turbidity-current channels
; Climate models
; Debris
; Geomorphology
; Glacial geology
; Landforms
; Ocean currents
; Sea ice
; Sediment transport
; Sedimentation
; Slope stability
; Turbidity
; Sedimentology
; deglaciation
; fine grained sediment
; fjord
; fluvial deposit
; glacier retreat
; glaciomarine deposit
; lamination
; meltwater
; moraine
; Northern Hemisphere
; seafloor
; sedimentation rate
; seismicity
; swath bathymetry
; tectonic wedge
; tidewater glacier
; turbidity
; turbidity current
; underwater environment
; Alaska
; Chile
; United States
英文摘要: Chilean fjords are the lowest latitude at which glaciers reach the sea today. High accumulation and mass throughput sustain tidewater glacier margins in this relatively mild climatic and oceanographic setting. 27,000 km2 of swath bathymetry allow mapping of sea-floor landforms and inferences on glacimarine sediments and sedimentation. Tidewater glaciers are present in several fjords. Beyond retreating Tempano glacier, a terminal moraine marks the limit of probable Little Ice Age advance with smaller transverse ridges closer to the glacier. Beyond advancing Pio XI Glacier there are few signs of organised submarine landforms. Older moraine ridges along several fjords formed at still-stands during deglaciation. Elsewhere, meltwater-fed braided rivers connect the glacial and marine sedimentary systems. Swath imagery shows glacifluvial and fluvial deltas with small channels and chutes that develop into long and sinuous turbidity-current channels. Few iceberg ploughmarks and submarine slope failures were observed, but several fields of pockmarks were present. The fjords of Chile are dominated by sediment delivery from turbid meltwater which distributes fine-grained debris widely, producing sorted and laminated fine-grained ice-proximal wedges and draping ice-distal seismic architecture to give a predominantly smooth sea floor. Turbidity currents also transfer sediments to some ice-distal environments. The Chilean fjordlands represent the mildest climatic and oceanographic end-member of a continuum of glacier-influenced marine settings; similar to south-east Alaska in the northern hemisphere. Components of a landform-assemblage model for climatically mild meltwater-dominated fjords include ice-contact moraine ridges, glacifluvial and fluvial deltas, and turbidity-current channels. Full-glacial and deglacial streamlined subglacial landforms are likely to have been buried in many areas by subsequent glacimarine sedimentation. © 2012 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60696
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: Scott Polar Research Institute, University of Cambridge, Cambridge CB2 1ER, United Kingdom; Hydrographic and Oceanographic Service of the Chilean Navy (SHOA), Errázuriz 254 Playa Ancha, P.O. Box 324, Valparaiso 236-0167, Chile
Recommended Citation:
Dowdeswell J.A.,Vásquez M.. Submarine landforms in the fjords of southern Chile: Implications for glacimarine processes and sedimentation in a mild glacier-influenced environment[J]. Quaternary Science Reviews,2013-01-01,64