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DOI	10.1130/B31658.1
	Eustatic sea-level controls on the flushing of a shelf-incising submarine canyon
	Allin J.R.; Hunt J.E.; Clare M.A.; Talling P.J.
发表日期	2018
ISSN	167606
起始页码	222
结束页码	237
卷号	130 期号:2021-01-02
英文摘要	Turbidity currents are the principal processes responsible for carving submarine canyons and maintaining them over geological time scales. The turbidity currents that maintain or "flush" submarine canyons are some of the most voluminous sediment transport events on Earth. Long-term controls on the frequency and triggers of canyon-flushing events are poorly understood in most canyon systems due to a paucity of long sedimentary records. Here, we analyzed a 160-m-long Ocean Drilling Program (ODP) core to determine the recurrence intervals of canyonflushing events in the Nazaré Canyon over the last 1.8 m.y. We then investigated the role of global eustatic sea level in controlling the frequency and magnitude of these canyonflushing events. Canyon-flushing turbidity currents that reach the Iberian Abyssal Plain had an average recurrence interval of 2770 yr over the last 1.8 m.y. Previous research has documented no effect of global eustatic sea level on the recurrence rate of canyon flushing. However, we find that sharp changes in global eustatic sea level during the mid- Pleistocene transition (1.2-0.9 Ma) were associated with more frequent canyon-flushing events. The change into high-amplitude, long-periodicity sea-level variability during the mid-Pleistocene transition may have remobilized large volumes of shelf sediment via subaerial weathering, and temporarily increased the frequency and magnitude of canyon-flushing turbidity currents. Turbidite recurrence intervals in the Iberian Abyssal Plain have a lognormal distribution, which is fundamentally different from the exponential distribution of recurrence intervals observed in other basin turbidite records. The lognormal distribution of turbidite recurrence intervals seen in the Iberian Abyssal Plain is demonstrated to result from the variable runout distance of turbidity currents, such that distal records are less complete, with possible influence from diverse sources or triggering mechanisms. The changing form of turbidite recurrence intervals at different locations down the depositional system is important because it ultimately determines the probability of turbidity current-related geohazards. © 2017 Geological Society of America.
语种	英语
来源期刊	Bulletin of the Geological Society of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185109
作者单位	National Oceanography Centre, University of Southampton Waterfront Campus, European Way, Southampton, SO14 3ZH, United Kingdom; School of Ocean and Earth Sciences, University of Southampton Waterfront Campus, European Way, Southampton, SO14 3ZH, United Kingdom; Departments of Earth Sciences and Geography, University of Durham, Durham, DH1 3LE, United Kingdom; School of Geography and Environment, Oxford University Centre for the Environment (OUCE), University of Oxford, South Parks Road, Oxford, OX1 3QY, United Kingdom
推荐引用方式 GB/T 7714	Allin J.R.,Hunt J.E.,Clare M.A.,et al. Eustatic sea-level controls on the flushing of a shelf-incising submarine canyon[J],2018,130(2021-01-02).
APA	Allin J.R.,Hunt J.E.,Clare M.A.,&Talling P.J..(2018).Eustatic sea-level controls on the flushing of a shelf-incising submarine canyon.Bulletin of the Geological Society of America,130(2021-01-02).
MLA	Allin J.R.,et al."Eustatic sea-level controls on the flushing of a shelf-incising submarine canyon".Bulletin of the Geological Society of America 130.2021-01-02(2018).