DOI: 10.1016/j.quascirev.2016.09.013
Scopus记录号: 2-s2.0-84994037062
论文题名: Micromorphology of diamicton affected by iceberg-keel scouring, Scoresby Sund, East Greenland
作者: Linch L.D. ; Dowdeswell J.A.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2016
卷: 152 起始页码: 169
结束页码: 196
语种: 英语
英文关键词: Diamicton
; East Greenland
; Gouges
; Ice-rafted debris (IRD)
; Iceberg scours
; Micromorphology
; Ploughmarks
; Scoresby sund
Scopus关键词: Deformation
; Morphology
; Naval architecture
; Offshore structures
; Sediments
; Diamicton
; Gouges
; Greenland
; Ice rafted debris
; Micromorphologies
; Ploughmarks
; Scoresby sund
; Sea ice
; deformation
; diamicton
; fault gouge
; ice-rafted debris
; iceberg
; installation
; micromorphology
; offshore engineering
; reworking
; scour
; seafloor
; water depth
; Arctic
; East Greenland
; Greenland
; Scoresby Sund
英文摘要: Icebergs are important as agents of deposition and seafloor reworking on glacier-influenced continental margins. When the keel of an iceberg exceeds water depth it ploughs through soft sediments producing scours/ploughmarks that can be kilometres long, hundreds of metres wide and sometimes tens of metres deep. Because the influence of iceberg keels on sediment is a critical factor when offshore structures (e.g. pipelines, power cables) are installed, the surface morphology of iceberg scours on the seafloor is relatively well-documented. Less however, is known about sub-scour deformation below the seafloor. This is particularly true of iceberg scoured diamicton (poorly sorted sediment comprising a variety of particle sizes), which is present in many high-latitude fjords and continental shelves. The aim of this research is to examine directly (macroscopically and microscopically, with thin sections) the style and intensity of deformation caused by the scouring action of iceberg keels in diamicton offshore of East Greenland. Results show that a distinctive suite of deformation structures (individual structures and overprinted structural patterns) dominated by planar shear, sediment mixing and high porewater, and dropstones characterises iceberg scoured diamicton. In addition, diamicton from areas of high-intensity iceberg scouring tends to show a wider variety, higher frequency and distribution, more abundant and better-developed deformation structures than diamicton from areas of intermediate- and low-intensity iceberg scouring. Characterising the effects of iceberg scour in diamicton is important more widely to inform: i) reconstruction of the geometry and dynamics of former ice sheets; and ii) installation and protection of offshore engineering structures in diamicton where iceberg scouring presents a geohazard. The value of micromorphology is significant especially in the absence of macroscopic sediment exposures/outcrops where the study of cores is necessary instead. © 2016 Elsevier Ltd Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/59408
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: School of Environment and Technology, University of Brighton, Lewes Road, United Kingdom; Scott Polar Research Institute, University of Cambridge, Lensfield Road, Cambridge, United Kingdom
Recommended Citation:
Linch L.D.,Dowdeswell J.A.. Micromorphology of diamicton affected by iceberg-keel scouring, Scoresby Sund, East Greenland[J]. Quaternary Science Reviews,2016-01-01,152