scholarly journals The Spatial Distribution of Bed Sediment on Fluvial System: A Mini Review of the Aceh Meandering River

2016 ◽  
Vol 5 (2) ◽  
Author(s):  
Muhammad Irham
Keyword(s):  
Spatial Distribution ◽  
Bed Load ◽  
Sieve Analysis ◽  
Left Bank ◽  
Fluvial System ◽  
Dynamic Interactions ◽  
Meandering River ◽  
River Bed ◽  
Meander Bends ◽  
Mechanical Weathering

Dynamic interactions of hydrological and geomorphological processes in the fluvial system result in accumulated deposit on the bed because the capacity to carry sediment has been exceeded. The bed load of the Aceh fluvial system is primarily generated by mechanical weathering resulting in boulders, pebbles, and sand, which roll or bounce along the river bed forming temporary deposits as bars on the insides of meander bends, as a result of a loss of transport energy in the system. This dynamic controls the style and range of deposits in the Aceh River. This study focuses on the spatial distribution of bed-load transport of the Aceh River. Understanding the spatial distribution of deposits facilitates the reconstruction of the changes in controlling factors during accumulation of deposits. One of the methods can be done by sieve analysis of sediment, where the method illuminates the distribution of sediment changes associated with channel morphology under different flow regimes. Hence, the purpose of this mini review is to investigate how the sediment along the river meander spatially dispersed. The results demonstrate that channel deposits in the Aceh River are formed from four different type of materials: pebble deposited along upstream left bank; sand located on the upstream, downstream, and along meander belts; and silt and clay located along the cut bank of meander bends. Because of different depositional pattern, the distribution of the sediment along the river can be used as a surrogate to identify bank stability, as well as to predict critical geometry for meander bend initiation

scholarly journals PENGARUH PERGERAKAN MEANDER TERHADAP KESEIMBANGAN ALUR SUNGAI

2019 ◽  
Vol 1 (2) ◽  
pp. 45
Author(s):  
Siti Murniningsih
Keyword(s):  
Sediment Load ◽  
Low Impact Development ◽  
Channel Cross Section ◽  
Fluvial System ◽  
Outer Banks ◽  
Meandering River ◽  
Sediment Loads ◽  
Meander Bends ◽  
Minimum Velocity ◽  
Sedimentation Processes

<span><em>Most of the river in Indonesia has a meander area especially located at the lower reach. Since the pattern of </em><span><em>the community behaviour in Indonesia, people live in surrounding or along the river while the river plains </em><span><em>and delta consist of alluvial soils, thus, meander migration usually occurs as a response to natural or manmade disturbances of the fluvial system. Meander River in urban area usually encourage sediment transport </em><span><em>problem such as riverbed aggradations at the area surrounding inside of the bank then will decrease the </em><span><em>river capacity in retaining flood while simultaneously eroding on the outer banks of meander bends. </em><span><em>Regarding velocity distribution at the channel cross section, the minimum velocity is occurring on the inside </em><span><em>of the meander, therefore some of the sediment loads is deposited. Related with the phenomena, protection </em><span><em>against sedimentation and erosion along meandering river extremely needed. Previously, river adjustment </em><span><em>within meander area are continually being made, therefore, eventually the gradient of a stream is altered to </em><span><em>accommodate the volume of water and the velocity necessary to transport the sediment load. In this paper,</em><span><em>understanding of various phenomenon’s in the meander area due to the sedimentation processes are </em><span><em>described and propose the new concept of protection with low impact development (LID) approach.</em></span></span></span></span></span></span></span></span></span></span></span><br /><br class="Apple-interchange-newline" /></span>

Estrutura dos depósitos sedimentares quaternários da bacia hidrográfica do rio Santana, Miguel Pereira, Estado do Rio de Janeiro

1999 ◽  
Vol 22 ◽  
pp. 8-22 ◽  
Author(s):  
Claudio Valdetaro Madeira ◽  
Leonardo Borghi
Keyword(s):  
Alluvial Fans ◽  
Fluvial System ◽  
Soil Horizons ◽  
Hydrographic Basin ◽  
Sedimentary Deposits ◽  
River Bed ◽  
Anthropogenic Action ◽  
High Terrace ◽  
Crevasse Splay ◽  
Geomorphological Features

The present work deals with stratigraphy, sedimentology and geomorphology of Quaternary sedimentary deposits of Santana river hydrographic basin. through facies and arquitectural elements descriptions. Based on five arquitectural elements characterized by ten lithofacies the following structural and depositional evolutions were scheduled: 1) formation of thick soil horizons over the basement; 2) deposition of several alluvial fans on the soils (lithofacies Gm and Fm, element E); 3) above an unconformity we can recognize a fluvial system, characterized by a non well drainage floodplain. This floodplain is overlaid by high-sinuosity channels (lithofacies Sp and St, element C) genetically related to other floodplain (lithofacies Fl and Fsc, element A) where the interfigering with crevasse splay deposits (lithofacies Sh, Sl, and Sp, element B) is ususal; 4) an erosional phase suceed by a new depositional phase characterized by low-sinuosity channels (lithofacies Gp, Gt, Sp, St, and Sh, element D). Nowadays anthropogenic action produces a new erosional phase. The geomorphological features recognized were scheduled: 1) the present floodplain 1.5m above the river bed; 2) the low terrace ( named T2) 5m above the river bed and its deposits is related to element D; 3) the high terrace ( named T1) 11m above the river bed and its deposits is related to elements A, B, C and E.

scholarly journals Heavy metal distribution in sediments around the offshore tin mining area of Central Bangka Regency, Indonesia

2021 ◽  
Vol 926 (1) ◽  
pp. 012027
Author(s):  
Irvani ◽  
S Adibrata ◽  
M Yusuf ◽  
M Hudatwi ◽  
A Pamungkas
Keyword(s):  
Heavy Metals ◽  
Spatial Distribution ◽  
Active Surface ◽  
Fine Sand ◽  
Mining Area ◽  
Pollution Load Index ◽  
Coarse Sand ◽  
Sieve Analysis ◽  
Marine Animals ◽  
Type Composition

Abstract Vary heavy metals scattered in suspension loads and re-sedimentation from the tailing of the offshore-alluvial tin mining at Tanah Merah and its surroundings, Central Bangka Regency. Research is needed to determine the type, composition, spatial distribution of heavy metals, and potential pollution. The active surface-sediments were taken from shallow marine systematically around the offshore tin mining area in the east season. Geochemical analysis of sediment using x-ray fluorescence, coupled with minerals and sieve analysis, and support by spatial analysis. These sediments have dominant the sand-size (range very-fine sand to coarse sand) and silt, contained predominantly large quantities of quartz minerals and shell fragments of marine animals. The metals are in the following decreasing order: Cr>Zn>Pb>Ni>Cu>As>Co>Cd. The spatial distribution of heavy metals generally has a relatively south, east, and north position, with concentrations occurring along the coastline and showing the degradation composition towards the open sea. The marine sediments are uncontaminated to moderately contaminated by Cd and Pb, indicate both natural and anthropogenic enrichment, low the pollution load index (PLI), and have various potential ecological risks index (RI) (low to very high RI).

scholarly journals A New Sequence Stratigraphic Framework of Terrestrial Fluvial

2017 ◽  
Vol 4 (1) ◽  
pp. 85 ◽  
Author(s):  
Zhipeng Lin ◽  
Le Chen ◽  
Jingfu Shan ◽  
Tan Zhang ◽  
Qianjun Sun ◽  
...  
Keyword(s):  
Deposition Process ◽  
Vital Role ◽  
Fluvial System ◽  
Fluvial Systems ◽  
Sequence Stratigraphic ◽  
Meandering River ◽  
River Types ◽  
Stratigraphic Framework ◽  
Different Characteristics ◽  
System Tract

Currently, the recognition and research on the classification of fluvial types mainly focus on the description and results of a series of indicators, such as the plane shape and sediment characteristics. However, there is limited literacy about how to demonstrate the fluvial types from the depositional process, especially less on sequence model of inland fluvial. Thus, this paper aims o propose a new kind of sequence stratigraphic framework, which is able to reflect the fluvial processes under the perspective of sequence stratigraphy. Accordingly, we use the principle of concrete analysis for concrete problems by comprehensively summing up the previous classification schemes of river types. With the research method of sedimentation process, new fluvial systems tracts for fluvial are presented here, including four parts: low fluvial system tract (LFST), advancing fluvial system tract (AFST), flooding fluvial system tract (FFST), receding fluvial system tract (RFST). Moreover, these could be applied to tackle the problem of the traditional division of fluvial. Various rivers have the different characteristics of systems tracts, then this may play a vital role in the discrimination of meandering river, braided river, anastomosing river and branched river. This study embodies the philosophical thought of Process Sedimentology and may contribute to revealing the deposition process of the fluvial system more profoundly from the aspect of genetic mechanism and evolution course. Most importantly, the fluvial classification system is definitely improved from the description stage to a complete rational stage.

Using Diatoms as Ecological and Paleoecological Indicators in Riverine Environments

2007 ◽  
Vol 13 ◽  
pp. 121-130
Author(s):  
Jeffery R. Stone
Keyword(s):  
Spatial Distribution ◽  
Environmental Changes ◽  
Climatic Factors ◽  
Diatom Assemblages ◽  
Meandering River ◽  
Rates Of Change ◽  
Terminal Lakes ◽  
Riverine Systems ◽  
The Impact ◽  
Selection Of

Fossil diatom assemblages are useful for reconstructing past environmental changes in riverine systems. However, few studies have attempted to utilize paleolimnological techniques in these settings. Analysis of sediments from riverine environments can provide key information predating the impact of human development, which cannot be acquired by other means. Paleolimnological techniques can be used to determine the natural variability in these systems and to estimate the magnitude and rates of change that the environment may have undergone as a result of anthropogenic or climatic factors, and to provide realistic goals for management of negatively-impacted systems.Reconstructing past riverine settings requires an understanding of the factors that control the spatial distribution of diatoms in riverine settings; this paper discusses the impact of resources, stressors, and disturbance events, which are the primary controls on the distribution of benthic diatoms in modern riverine environments. A selection of case studies that utilize paleolimnological techniques to infer past stream hydrology are also discussed; these examples encompass the use of fossil diatom assemblages from sediments recovered from lowland floodplain and meandering river systems, estuarine environments, fluvial lakes, arctic deltaic environments, and terminal lakes.

Sorting of Bed Load Sediment by Flow in Meander Bends

1985 ◽  
Vol 21 (9) ◽  
pp. 1361-1373 ◽  
Author(s):  
Gary Parker ◽  
E. D. Andrews
Keyword(s):  
Bed Load ◽  
Meander Bends ◽  
Load Sediment

scholarly journals Evidence of, and a Proposed Explanation for, Bimodal Transport States in Alluvial Rivers

2017 ◽  
Author(s):  
Kieran B. J. Dunne ◽  
Douglas J. Jerolmack
Keyword(s):  
Grain Size ◽  
Shear Stress ◽  
Critical Shear Stress ◽  
Bed Load ◽  
Bed Sediments ◽  
Channel Geometry ◽  
Alluvial Rivers ◽  
River Bed ◽  
Tentative Evidence ◽  
Near Threshold

Abstract. Gravel-bedded rivers organize their bankfull channel geometry and grain size such that shear stress is close to the threshold of motion. Sand-bedded rivers on the other hand typically maintain bankfull fluid stresses far in excess of threshold, a condition for which there is no satisfactory understanding. A fundamental question arises: Are bed-load (gravel-bedded) and suspension (sand-bedded) rivers two distinct equilibrium states, or do alluvial rivers exhibit a continuum of transport regimes as some have recently suggested? We address this question in two ways: (1) re-analysis of global channel geometry datasets, with consideration of the dependence of critical shear stress upon site-specific characteristics (e.g. slope and grain size); and (2) examination of a longitudinal river profile as it transits from gravel to sand-bedded. Data reveal that the transport state of alluvial river-bed sediments is bimodal, showing either near-threshold or suspension conditions, and that these regimes correspond to the respective bimodal peaks of gravel and sand that comprise natural river-bed sediments. Sand readily forms near-threshold channels in the laboratory and some field settings, however, indicating that another factor, such as bank cohesion, must be responsible for maintaining suspension channels. We hypothesize that alluvial rivers adjust their geometry to the threshold-limiting bed and bank material – which for gravel-bedded rivers is gravel, but for sand-bedded rivers is mud (if present) – and present tentative evidence for this idea.

scholarly journals VARIABILITY OF SEDIMENT TRANSPORT IN THE SCOTT RIVER CATCHMENT (SVALBARD) DURING THE HYDROLOGICALLY ACTIVE SEASON OF 2009

2014 ◽  
Vol 33 (1) ◽  
pp. 39-49 ◽  
Author(s):  
Waldemar Kociuba ◽  
Grzegorz Janicki ◽  
Krzysztof Siwek
Keyword(s):  
Bedload Transport ◽  
Bed Load ◽  
River Catchment ◽  
Active Season ◽  
Fluvial Transport ◽  
River Bed ◽  
Load Transport ◽  
Bed Load Transport ◽  
Glacial River ◽  
Local Intensity

Abstract Investigations of fluvial transport in the glacial river catchment (Scott River, Spitsbergen) were conducted in the melt season of 2009. A special attention was given to dynamics and distribution of bedload transport − the major component of fluvial transport in a proglacial gravel-bed river. Bed-load transport rate was determined using the River Bedload Traps (RBT) constructed for the project’s need. The obtained results indicate high diversity of bedload transport, the amount of which reached up to 220 kg m-1 day-1 for twenty-four hours in particular measurement sites. The results confirmed also great variability of local intensity fluvial processes in polar zone.

scholarly journals Formation and movement of ice accumulation waves under ice cover –an experimental study

2019 ◽  
Vol 67 (2) ◽  
pp. 171-178 ◽  
Author(s):  
Jun Wang ◽  
Yifan Wu ◽  
Jueyi Sui ◽  
Bryan Karney
Keyword(s):  
Ice Cover ◽  
Bed Load ◽  
Transport Capacity ◽  
Ice Jams ◽  
Frazil Ice ◽  
Ice Accumulation ◽  
River Bed ◽  
Ice Conditions ◽  
Formation And Evolution ◽  
Good Agreement

Abstract Ice jams in rivers often arise from the movement of frazil ice as cover-load under ice cover, a process which is conceptually similar to the movement of sediment as bed-load along a river bed. The formation and movement of an ice-accumulation wave is one facet of a larger class of cover-load movements. The movement of an ice-accumulation wave obviously plays a crucial role in the overall process of ice accumulation. In the present study, experiments under different flow and ice conditions help reveal the mechanics of formation and evolution of ice-accumulation waves. In particular, suitable criteria for formation of an ice-accumulation wave are investigated along with the resulting speed of wave propagation. The transport capacity of frazil ice under waved accumulation is modeled by comparing those of experiments collected in laboratories, and the resulting equation is shown to be in good agreement with measured experimental results.

Sign in / Sign up

Export Citation Format

Share Document