scholarly journals Uplift Quantification and Erosion Rate Estimation in Northwestern Tunisia from Topographic and Lithologic Data

2021 ◽  
Vol 10 (1) ◽  
pp. 15
Author(s):  
Hania Saadouni ◽  
Rabah Alouani
Keyword(s):  
Erosion Rate ◽  
Morphological Features ◽  
Northern Tunisia ◽  
Tectonic Model ◽  
Digital Elevation ◽  
Rate Calculation ◽  
Erosion Mechanisms ◽  
Topographic Evolution ◽  
Transcurrent Faults ◽  
Regional Tectonics

Digital elevation modeling (DEM) was used to determine key morphological features such as hypsometry, slopes and topographic evolution in correlation with tectonic regimes and erosion mechanisms. This contribution discusses the tectonic model of northern Tunisia, which since 1977 has been described by geologists as an allochthonous unity domain of the Serravallian-Tortonian. This study presents new data from the erosion rate calculation following the establishment of these units and then proposes another view on regional tectonics. Therefore, the example used of Oued Sedjnene gives a rising rate of the order of 0.01 mm/year, almost equivalent to the results found in surrounding medeterranean belt (ex. Italy and Turkey). The structure and geomorphology of northern Tunisia is a result of folding of Cenozoic basin. However located tangential structure are related to transcurrent faults and not overthrust structure.

scholarly journals Effect of DEM Resolution on Erosion in Batang Kuranji Watershed

2020 ◽  
Vol 15 (2) ◽  
pp. 20
Author(s):  
Elvi Roza Syofyan ◽  
Bambang Istijono ◽  
Amrizal Saidi ◽  
Revalin Herdianto
Keyword(s):  
Soil Erosion ◽  
Land Cover ◽  
Sea Level ◽  
Erosion Rate ◽  
Class Ii ◽  
Class I ◽  
Hazard Class ◽  
Dem Resolution ◽  
Main River ◽  
Rate Calculation

Batang Kuranji Watershed is one of the region river at Indragiri - Akuaman with a total area of Watershed 224.7 km2 consisting of Batang Sungai Sapiah Sub Watershed, Batang Danau Limau Manih Sub Watershed, Batang Sungkai Sub Watershed, Batang Bukik Tindawan Sub Watershed and Batang Padang Janiah Sub Watershed. Batang Kuranji flows from upstream of the Bukit Barisan with the highest elevation + 1,605 meters above sea level at the peak of Bukit Tinjau Laut and empties into the Padang beach with a main river length of ± 32.41. DEM has an influence on the results of land erosion by affecting the slope accuracy. The higher the DEM resolution, the more precise the results of the soil erosion simulation. With the Musle method the rate of erosion occurs in the Batang Kuranji watershed, with DEM data of 8m and land cover in 2017, an erosion rate of 23.91 tons / ha / year is classified in hazard class II (light), DEM data of 30m erosion rate is 7. 70 tons / ha / year are classified in hazard class I (very mild), with DEM data of 90m erosion rate of 4.54 tons / ha / year classified in hazard I class (very light). It can be seen that the higher the DEM resolution, the more accurate the erosion rate calculation in the watershed.

scholarly journals Ring-shaped morphological features and interpreted small seamounts between southern Quebec (Canada) and the New England seamounts (USA) and their possible association with the New England hotspot track

2018 ◽  
pp. 223-265
Author(s):  
Ronald T. Marple ◽  
James D. Hurd, Jr. ◽  
Robert J. Altamura
Keyword(s):  
New England ◽  
Continental Slope ◽  
Gulf Of Maine ◽  
Morphological Features ◽  
Cape Cod ◽  
Digital Elevation ◽  
Igneous Province ◽  
Seamount Chain ◽  
Elevation Model ◽  
Digital Elevation Model Data

 Enhancements of recently available high-resolution multibeam echosounder data from the western Gulf of Maine and Atlantic continental margin and light detection and ranging (LiDAR) and digital elevation model data from southeastern Quebec (Canada) and the northeastern United States have revealed numerous ring-shaped morphological features and interpreted small seamounts between the Monteregian Hills igneous province and the New England seamounts. The morphological features onshore are mainly ring-shaped depressions, several of which surround mapped igneous intrusions in the Monteregian Hills igneous province and White Mountain magma series. Most of the rings offshore are also depressions, although a few rings are curved ridges above the seafloor. The largest ring in the western Gulf of Maine is the 30-km-diameter Tillies ring that lies 20 km east of Cape Ann, MA. Several small (<3 km in diameter) round, flat-topped submerged hills that we interpret to be volcanic necks are also present beneath the western Gulf of Maine. The rings between Cape Cod and the continental slope are more subtle because of thicker sediments and poorer spatial resolution of the sonar data in this area. The southernmost ring-shaped features are located on the continental slope and upper continental rise and coincide with the northwestern end of the New England seamount chain. The concentration of these features between the Monteregian Hills igneous province and the New England seamounts suggests that they are igneous features that may be associated with the New England hotspot track. 

scholarly journals Relationship Between Dams, Knickpoints and the Longitudinal Profile of the Upper Indus River

2021 ◽  
Vol 9 ◽  
Author(s):  
Liqin Zhou ◽  
Weiming Liu ◽  
Xiaoqing Chen ◽  
Hao Wang ◽  
Xudong Hu ◽  
...  
Keyword(s):  
Debris Flow ◽  
Field Work ◽  
Longitudinal Profile ◽  
Srtm Dem ◽  
Indus River ◽  
Digital Elevation ◽  
Regional Tectonic ◽  
Channel Steepness ◽  
The Relationship ◽  
Regional Tectonics

Mass movements in mountainous areas are capable of damming rivers and can have a lasting effect on the river longitudinal profile. The long profile is commonly used to retrieve regional tectonic information, but how much dams may compromise geomorphometry-based tectonic analysis has not been systematically researched. In this study, we investigate the relationship between river dams and the longitudinal profile of the upper Indus River basin, based on interpretation and analysis of remote sensing imagery and digital elevation models (DEMs) and local field work. We identified 178 landslide, glacier and debris flow dams. Using TopoToolbox, we automatically extracted the river longitudinal profile from the 30 m SRTM DEM, determined the location of convex knickpoints and calculated the channel steepness index. One hundred and two knickpoints were detected with heights above 148 m, of which 55 were related to dams. There is good spatial correspondence between dams, convexities in the river longitudinal profile and relatively high steepness index. Different dam types have different impacts on the river profile; on the upper Indus, debris flow dams have a greater impact than landslide and glacier dams and can form knickpoints of up to 900 m. Therefore, dams may have a significant influence on the river longitudinal profile, knickpoints and steepness index, and should be considered when extracting information on regional tectonics using these indices.

Prediction of Erosion of Polyetherimide and Its Composites Using Response Surface Methodology

2014 ◽  
Vol 137 (1) ◽  
Author(s):  
Avinash A. Thakre
Keyword(s):  
Response Surface Methodology ◽  
Steady State ◽  
Glass Fiber ◽  
Response Surface ◽  
Impact Velocity ◽  
Erosion Rate ◽  
Quadratic Model ◽  
Impingement Angle ◽  
Glass Fiber Composites ◽  
Erosion Mechanisms

This paper presents an approach to establish the model for predicting the steady-state erosion rate of polyetherimide and its glass fiber composites. Three-factor and two-level, face-centered composite design is used for experimentation. The parameters which affect the erosion rate are selected as glass fiber percentage (0–40%), impingement angle (30 deg–90 deg), and impact velocity (30–90 m/s). Response surface methodology is used to derive second-order quadratic model with interactions. Investigation showed all the parameters have significant effect on controlling steady-state erosion rate of these composites. The interactions of impact velocity-fiber percentage and impact velocity-impingement angle are significant. The increase in erosion rate with the increase in impact velocity is found to be satisfying a power law. Maximum erosion rate for these composites found at around 45 deg–60 deg impingement angle indicates their semiductile erosion behavior. Scanning electron microscopy photographs indicate ploughing, microcutting, development of cracks, and exposure of fibers as the dominating erosion mechanisms for these composites.

scholarly journals Dynamics of gully side erosion: a case study using tree roots exposure data

2016 ◽  
Vol 8 (1) ◽  
Author(s):  
Karel Šilhán ◽  
Ivan Ružek ◽  
Libor Burian
Keyword(s):  
Detailed Analysis ◽  
Erosion Rate ◽  
Digital Elevation Models ◽  
Natural Process ◽  
Tree Roots ◽  
Exposure Data ◽  
Digital Elevation ◽  
The Mean ◽  
Reconstruction Period

AbstractErosion is a frequently studied natural process. Unfortunately, detailed analysis mostly requires longterm field monitoring or detailed digital elevation models (DEM) which are still absent for many areas. For these reasons we used the dendrogeomorphic method, a valuable tool for erosion analysis. The slopes of a ~220 m long gully close to the Kozárovce village (Slovakia) were the object of our study. We analyzed 53 tree root samples coming from 16 broad-leaved trees of different species. 23 erosion event years were explored during the reconstruction period AD 1972–2013. The mean erosion rate

scholarly journals Infra Red Aerial Photograph Interpretation for Soil Erosion at Wuryantoro, Wonogiri

2016 ◽  
Vol 15 (1) ◽  
pp. 29
Author(s):  
S Suharjo ◽  
Sugiharto Budi Santoso ◽  
Pujo Nur Cahyo ◽  
M Mulyono ◽  
Heru Sri Widodo
Keyword(s):  
Soil Erosion ◽  
Erosion Rate ◽  
Aerial Photograph ◽  
Research Area ◽  
Appropriate Technology ◽  
Earth Surface ◽  
Erosion Hazard ◽  
Soil Erosion Rate ◽  
Supporting Soil ◽  
Rate Calculation

Collecting data of soil erosion hazard terrestrially needs much time, high cost, and large energy. Therefore it is needed appropriate technology in addition to terrestrially decreasing necessity of time, cost and energy. Aerial photograph is picture of earth surface, which shape and place similar to condition on earth surface. Using aerial photograph in this research is expected to be able to take account for erosion factors. This research is conducted in Kecamatan Wuryantoro Kabupaten Wonogiri. Research method that used is aerial photograph interpretation with land unit approach. Amounts of soil lost are approached with USLE formula. Aerial photograph that used in this research is aerial photograph coloured infrared with 1:10.000 in scale and 1991 in year of taking photography. The result shows that using aerial photograph is very useful in supporting soil erosion rate calculation. Erosion rate at research area is 0.0968 ton/ha/year to 100.4344 ton/ha/year. This number is included in class of light erosion hazard (

scholarly journals Kajian Potensi Erosi Di Daerah Aliran Sungai Babon Menggunakan Permodelan GeoWEPP

G - SMART ◽  
2021 ◽  
Vol 3 (2) ◽  
pp. 98
Author(s):  
Revangga Dandha Pratama ◽  
Dimas Jalu Setyawan ◽  
Budi Santosa
Keyword(s):  
Erosion Rate ◽  
River Flow ◽  
Water Erosion ◽  
Climate Data ◽  
Erosion Prediction ◽  
Digital Elevation ◽  
Water Erosion Prediction Project ◽  
Type Data ◽  
Hazard Level ◽  
Elevation Model

At the time of the high intensity of rainfall in Semarang, the water contained in the Babon River had overflowed, resulting in flooding of parts of the area adjacent to the Babon river flow. This matter has many factors, there are erosion and sediment produced. This study aims to study erosion potential in the Babon watershed, using the Geospatial Interface for Water Erosion Prediction Project (GeoWEPP) modeling. The results of the modeling are the amount of erosion rate and erosion distribution in the study area. The erosion prediction period in this study is in 2006 - 2015. Data needed in GeoWEPP operation are Digital Elevation Model, climate data, land use data, and soil type data. Based on the GeoWEPP process in the Babon watershed the erosion rate was 36.1 tons / ha / year and the sediment yield was 26075.2 tons / year. From the results of the erosion rate produced divided by the reasonable erosion rate get the Erosion Hazard Level index (TBE) of 3.6 or including medium TBE. Based on the distribution of erosion maps produced, the area experienced the greatest erosion rate in the Ungaran region. This is due to the fact that it belongs to the highlands and has a high slope value.

scholarly journals Predicted ripple dimensions in relation to the precision of in situ measurements in the southern North Sea

Ocean Science ◽  
2016 ◽  
Vol 12 (6) ◽  
pp. 1221-1235 ◽  
Author(s):  
Knut Krämer ◽  
Christian Winter
Keyword(s):  
North Sea ◽  
Field Data ◽  
Morphological Features ◽  
Sediment Properties ◽  
Hydraulic Roughness ◽  
Digital Elevation ◽  
Shelf Sea ◽  
Waves And Currents ◽  
Accuracy Of Measurement

Abstract. Ripples are common morphological features in sandy marine environments. Their shapes and dimensions are closely related to local sediment properties and forcing by waves and currents. Numerous predictors for the geometry and hydraulic roughness of ripples exist but, due to their empirical nature, they may fail to properly reflect conditions in the field. Here, measurements of tide and wave generated ripples in a shallow shelf sea are reported. Discrete and continuous methods for the extraction of ripple dimensions from digital elevation models (DEMs) are inter-compared. The range of measured ripple dimensions is quantified and compared to the results of empirical predictors. The repeatability of a measurement for inactive conditions is taken as the precision of measurements of bedform dimensions. The accuracy of measurement is assessed via comparison to predicted dimensions. Results from field data show that the precision of measurements is limited to 10 % of the absolute ripple dimensions. The application of different methods for the detection of ripple heights may result in form roughness heights differing by a factor of up to 2 between the traditional statistical estimate and a full evaluation of the spatial bathymetry.

Wear Behavior of Laser Surface-Hardened Gray and Ductile Cast Irons. Part 2—Erosive Wear

1988 ◽  
Vol 110 (3) ◽  
pp. 462-466 ◽  
Author(s):  
P. A. Molian ◽  
Mark Baldwin
Keyword(s):  
Erosion Rate ◽  
Continuous Wave ◽  
Wear Behavior ◽  
Surface Hardness ◽  
Erosive Wear ◽  
Gray Iron ◽  
Case Depth ◽  
Cast Irons ◽  
Beneficial Effects ◽  
Erosion Mechanisms

A 1.2-kW, continuous wave, CO2-gas laser was used to transformation harden or melt the surface of gray and ductile cast irons. Effects of surface-hardened layers on solid particle erosion showed that the erosion rate decreased with an increase in surface hardness and case depth. The order of matrix microstructures that increased the erosion rate were ledeburite, tempered martensite, and pearlite. These results were opposite to those observed in bulk-hardened alloys. Erosion mechanisms of brittle, gray iron included micromachining in the untreated condition and grain boundary cracking in the laser-treated condition. In contrast, erosion modes of ductile iron were plastic flow followed by cracking in the untreated condition and platelet formation and fatigue in the laser-treated conditions. The beneficial effects of surface hardening on erosion were examined and discussed.

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