Characteristics of sediment dynamics following large-scale sediment supply events in mountain watersheds in Japan

<p>The Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma) was the most marked climate warming event of the Cenozoic, and a potentially useful deep time analogue for understanding environmental responses to anthropogenic carbon emissions and associated warming. The response of sedimentary systems to the large-scale climate changes of the PETM are, however, still uncertain. Here, we present an extremely thick (~140 m) record of the PETM in cores from a well in the North Sea, offshore UK. In this well, a thick Paleocene-Eocene interval is developed owing to uplift of the East Shetland Platform in the late Paleocene. Carbon isotope data through this well, coupled with detailed sedimentological analysis, show that the PETM interval is contemporaneous with >200 sandstone turbidites layers. Mud deposition without turbidites dominated sedimentation below and above the PETM. These observations support previous work from other localities highlighting how climate warming during the PETM likely drove substantial changes in hydrological cycling, erosion and sediment supply. Spectral analysis of turbidite recurrence in the PETM interval suggests that the abundance of turbidites was modulated in part by ~21 kyr astronomical precession climate cycles, further emphasizing a potential climatic control on turbidite sedimentation. In detail, we note a kiloyear-scale time lag between onset of the PETM carbon isotope excursion and the appearance of turbidites in the succession, highlighting a delay between PETM carbon release and warming and the basin-wide response in sediment supply.</p>

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Sediment Supply Explains Long‐Term and Large‐Scale Patterns in Salt Marsh Lateral Expansion and Erosion

Geophysical Research Letters ◽

10.1029/2019gl083315 ◽

2019 ◽

Vol 46 (20) ◽

pp. 11178-11187 ◽

Cited By ~ 6

Author(s):

Cai J.T. Ladd ◽

Mollie F. Duggan‐Edwards ◽

Tjeerd J. Bouma ◽

Jordi F. Pagès ◽

Martin W. Skov

Keyword(s):

Salt Marsh ◽

Large Scale ◽

Sediment Supply ◽

Lateral Expansion

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Supplied Sediment Tracking for Bridge Collapse with Large-Scale Channel Migration

Water ◽

10.3390/w12071881 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1881

Author(s):

Takuya Inoue ◽

Jagriti Mishra ◽

Kazuo Kato ◽

Tamaki Sumner ◽

Yasuyuki Shimizu

Keyword(s):

Erosion Rate ◽

Large Scale ◽

Bank Erosion ◽

Strong Relationship ◽

Sediment Supply ◽

Study Region ◽

Flow Discharge ◽

Bridge Abutment ◽

Bridge Collapse ◽

Flooding Events

Here, we provide a numerical model that assigns an identification number to trace sediments and also identify the source of sediment supply. We analyze the efficacy of our model by reproducing the reach-scale field observations from flooding events in 2010 and 2016 that affected Kyusen Bridge over the Bebetsu River, Hokkaido, Japan. Our simulation results can successfully reproduce and trace the formation of bars caused by sediment supply in the study region. Our study also suggests a strong relationship between bank erosion rate, sediment supply and flow-discharge. The bank erosion rate is higher when sediment supply increases, and bank erosion reduces as flow discharge goes down. The model can also replicate the changes in a bed concerning sediment supply and was used to reproduce the bridge-abutment failure caused by the 2016 flooding with large sediment supply and the bridge-pier failure caused by the 2010 flooding with less sediment supply.

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EXPERIMENTAL STUDY OF BAR FORMATION IN SAND BED CHANNEL

Jurnal Teknologi ◽

10.11113/jt.v78.8503 ◽

2016 ◽

Vol 78 (5-3) ◽

Author(s):

Duratul Ain Tholibon ◽

Junaidah Ariffin ◽

Jazuri Abdullah ◽

Juliana Idrus

Keyword(s):

Experimental Study ◽

Flow Rate ◽

Experimental Work ◽

Large Scale ◽

Sediment Supply ◽

Hydraulic Characteristics ◽

Flow Rates ◽

Physical Mechanisms ◽

Bed Slope ◽

Bar Formation

A large number of studies both theoretical and experimental have been devoted to understand the physical mechanisms underlying the bar formation. This can be investigated by carrying out an experimental work in an erodible sand bed channel using a large-scale physical river model. The study included the various hydraulic characteristics with steady flow rates and sediment supply. An experimental work consists of four matrices of flow rate and channel width with other variables namely grains size and bed slope were kept constant. Details of bar profile development that generated using Surfer, a software used for 3D elevation plots are included.

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Large-scale suspended sediment transport and sediment deposition in the Mekong Delta

Hydrology and Earth System Sciences ◽

10.5194/hess-18-3033-2014 ◽

2014 ◽

Vol 18 (8) ◽

pp. 3033-3053 ◽

Cited By ~ 50

Author(s):

N. V. Manh ◽

N. V. Dung ◽

N. N. Hung ◽

B. Merz ◽

H. Apel

Keyword(s):

Sediment Transport ◽

Suspended Sediment ◽

Large Scale ◽

Transport Model ◽

Mekong Delta ◽

Sediment Dynamics ◽

Sediment Deposition ◽

Mineral Fertilizers ◽

Suspended Sediment Transport ◽

Extreme Flood

Abstract. Sediment dynamics play a major role in the agricultural and fishery productivity of the Mekong Delta. However, the understanding of sediment dynamics in the delta, one of the most complex river deltas in the world, is very limited. This is a consequence of its large extent, the intricate system of rivers, channels and floodplains, and the scarcity of observations. This study quantifies, for the first time, the suspended sediment transport and sediment deposition in the whole Mekong Delta. To this end, a quasi-2D hydrodynamic model is combined with a cohesive sediment transport model. The combined model is calibrated using six objective functions to represent the different aspects of the hydraulic and sediment transport components. The model is calibrated for the extreme flood season in 2011 and shows good performance for 2 validation years with very different flood characteristics. It is shown how sediment transport and sediment deposition is differentiated from Kratie at the entrance of the delta on its way to the coast. The main factors influencing the spatial sediment dynamics are the river and channel system, dike rings, sluice gate operations, the magnitude of the floods, and tidal influences. The superposition of these factors leads to high spatial variability of sediment transport, in particular in the Vietnamese floodplains. Depending on the flood magnitude, annual sediment loads reaching the coast vary from 48 to 60% of the sediment load at Kratie. Deposited sediment varies from 19 to 23% of the annual load at Kratie in Cambodian floodplains, and from 1 to 6% in the compartmented and diked floodplains in Vietnam. Annual deposited nutrients (N, P, K), which are associated with the sediment deposition, provide on average more than 50% of mineral fertilizers typically applied for rice crops in non-flooded ring dike floodplains in Vietnam. Through the quantification of sediment and related nutrient input, the presented study provides a quantitative basis for estimating the benefits of annual Mekong floods for agriculture and fishery, and is an important piece of information with regard to the assessment of the impacts of deltaic subsidence and climate-change-related sea level rise on delta morphology.

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The impact of tidal stream turbines on large-scale sediment dynamics

Renewable Energy ◽

10.1016/j.renene.2009.06.015 ◽

2009 ◽

Vol 34 (12) ◽

pp. 2803-2812 ◽

Cited By ~ 157

Author(s):

Simon P. Neill ◽

Emmer J. Litt ◽

Scott J. Couch ◽

Alan G. Davies

Keyword(s):

Large Scale ◽

Sediment Dynamics ◽

Tidal Stream ◽

The Impact

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Impact of large-scale reclamation on hydro-sediment dynamics in the open shallow seas

OCEANS 2016 - Shanghai ◽

10.1109/oceansap.2016.7485422 ◽

2016 ◽

Author(s):

Yaqian Yao ◽

Luying Liu ◽

Wenke Ge ◽

Yanming Yao

Keyword(s):

Large Scale ◽

Sediment Dynamics ◽

Shallow Seas

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Integration of shelf evolution and river basin models to simulate Holocene sediment dynamics of the Humber Estuary during periods of sea-level change and variations in catchment sediment supply

The Science of The Total Environment ◽

10.1016/s0048-9697(03)00081-0 ◽

2003 ◽

Vol 314-316 ◽

pp. 737-754 ◽

Cited By ~ 21

Author(s):

I SHENNAN ◽

T COULTHARD ◽

R FLATHER ◽

B HORTON ◽

M MACKLIN ◽

...

Keyword(s):

Sea Level ◽

River Basin ◽

Sea Level Change ◽

Sediment Dynamics ◽

Sediment Supply ◽

Level Change ◽

Holocene Sediment ◽

Humber Estuary

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Early and middle Miocene ice sheet dynamics in the Ross Sea: Results from integrated core-log-seismic interpretation

Geological Society of America Bulletin ◽

10.1130/b35814.1 ◽

2021 ◽

Author(s):

Lara F. Pérez ◽

Laura De Santis ◽

Robert M. McKay ◽

Robert D. Larter ◽

Jeanine Ash ◽

...

Keyword(s):

Continental Shelf ◽

Large Scale ◽

Middle Miocene ◽

Ross Sea ◽

Ice Sheets ◽

Ice Sheet ◽

Sediment Supply ◽

Outer Continental Shelf ◽

Ice Caps ◽

Reflection Seismic

Oscillations in ice sheet extent during early and middle Miocene are intermittently preserved in the sedimentary record from the Antarctic continental shelf, with widespread erosion occurring during major ice sheet advances, and open marine deposition during times of ice sheet retreat. Data from seismic reflection surveys and drill sites from Deep Sea Drilling Project Leg 28 and International Ocean Discovery Program Expedition 374, located across the present-day middle continental shelf of the central Ross Sea (Antarctica), indicate the presence of expanded early to middle Miocene sedimentary sections. These include the Miocene climate optimum (MCO ca. 17−14.6 Ma) and the middle Miocene climate transition (MMCT ca. 14.6−13.9 Ma). Here, we correlate drill core records, wireline logs and reflection seismic data to elucidate the depositional architecture of the continental shelf and reconstruct the evolution and variability of dynamic ice sheets in the Ross Sea during the Miocene. Drill-site data are used to constrain seismic isopach maps that document the evolution of different ice sheets and ice caps which influenced sedimentary processes in the Ross Sea through the early to middle Miocene. In the early Miocene, periods of localized advance of the ice margin are revealed by the formation of thick sediment wedges prograding into the basins. At this time, morainal bank complexes are distinguished along the basin margins suggesting sediment supply derived from marine-terminating glaciers. During the MCO, biosiliceous-bearing sediments are regionally mapped within the depocenters of the major sedimentary basin across the Ross Sea, indicative of widespread open marine deposition with reduced glacimarine influence. At the MMCT, a distinct erosive surface is interpreted as representing large-scale marine-based ice sheet advance over most of the Ross Sea paleo-continental shelf. The regional mapping of the seismic stratigraphic architecture and its correlation to drilling data indicate a regional transition through the Miocene from growth of ice caps and inland ice sheets with marine-terminating margins, to widespread marine-based ice sheets extending across the outer continental shelf in the Ross Sea.

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