DOI: 10.1016/j.quascirev.2013.05.026
Scopus记录号: 2-s2.0-84882791602
论文题名: River entrenchment and terrace formation in the UK Holocene
作者: Macklin M.G. ; Lewin J. ; Jones A.F.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2013
卷: 76 起始页码: 194
结束页码: 206
语种: 英语
英文关键词: Environmental controls
; Flood events
; Holocene
; River incision
; River terraces
Scopus关键词: Anthropogenic effects
; Environmental control
; Flood event
; Flood risk management
; Holocenes
; Pleistocene sediments
; Regional similarities
; River terraces
; Catchments
; Flood control
; Floods
; Floors
; Rivers
; anthropogenic effect
; carbon isotope
; catchment
; database
; extreme event
; flooding
; geographical distribution
; glaciotectonics
; Holocene
; meta-analysis
; Pleistocene
; radiocarbon dating
; reworking
; river channel
; terrace
; United Kingdom
英文摘要: A meta-analysis of a large database of 14C dated fluvial units is used to assess the chronology and controls of episodic Holocene river entrenchment and terrace formation in the UK. Most Holocene terraces are of a 'fill-cut' type developed in Pleistocene sediments, in places now reaching down to pre-Holocene bedrock. Holocene terraces are widespread in higher-relief areas of the UK and peripheral higher-energy rivers, and include up to 7 levels in some valley floor reaches. Using 14C constrained data sub-sets for incision episodes, the onset, vertical ranges, formation times, and rates of entrenchment are examined, together with geographical distributions. The height range of terrace separation is relatively small (0.5-3.5m) with a long-term averaged incision rate over the late and mid-Holocene of 0.43, 0.5, 0.67, 0.7 and 0.81m/ka in the Tweed, Rheidol, Severn, Ouse and Ribble catchments, and a regional similarity in the scale of incision events. The periods 4200-3700, 3100-2900, 2100-1900, 1800-1500cal.BP and most notably the last 1000 years (with prominent peaks at 900-800 and 700-600cal.BP) were times of accelerated incision. It appears likely that extreme flood events triggered the formation of incision 'slots', rather than entrenchment being a direct response to glacio-tectonic uplift, or the result of incremental valley-floor lowering by combined incision and lateral reworking. River entrenchment has also been rapid in recent centuries, reflecting the coupling of extreme-events with anthropogenic effects on catchment hydrology. Incision results in changes of river channel flood power and overbank flood extent, and improved data on the long-term and large-scale vertical tendency of UK rivers are needed for flood risk management purposes. © 2013 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60545
Appears in Collections: 过去全球变化的重建
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作者单位: Centre for Catchment and Coastal Research and River Basin Dynamics and Hydrology Research Group, Institute of Geography and Earth Sciences, Aberystwyth University, Ceredigion SY23 3DB, United Kingdom; School of Geography, Planning and Environmental Policy, University College Dublin, E001 Newman Building, Belfield, Dublin 4, Ireland
Recommended Citation:
Macklin M.G.,Lewin J.,Jones A.F.. River entrenchment and terrace formation in the UK Holocene[J]. Quaternary Science Reviews,2013-01-01,76