Coastal Stability using Remote Sensing and Radioactive Materials in the Northwest Nile Delta Coast, Egypt

2021 ◽  
Vol 5 (1) ◽  
pp. 14-26
Author(s):  
Mamdouh El-Hattab ◽  
Ibrahim Saleh ◽  
Ayat Mohamed

This paper points to changes of the coastline using two ways, calculating the annual rate of erosion using 1) radioactive materials and 2) GIS and DSAS extension. Finally, both results were verified. Radioactivity results indicate both erosion and accretion zones, the annual scavenging rate in Promontory area shows that it is presented main accretion area, unlike the results of the DSAS extension, which showed that the Promontory is erosion area. The Burullus area annual scavenging rate results showing erosion, despite results of DSAS, it shows that it is an accretion area, but this was clarified by calculating the average distance between the shoreline of 2017 and 2018, and the 2018 shoreline retreat with an average distance 41.4 cm, which makes the Burullus region suffer from erosion. Two methods showed similarity in results in the Edco area, which shows that the Edco area suffers from erosion.

2020 ◽  
Vol 6 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Dao Dinh Cham ◽  
Nguyen Thai Son ◽  
Nguyen Quang Minh ◽  
Nguyen Tien Thanh ◽  
Tran Tuan Dung

Cua Dai estuary belonged to Quang Nam province is considered to be one of the localities of Vietnam having a complex erosion and accretion process. In this area, sandbars are recently observed with lots of arguments about the causes and regimes of formation. This could very likely result of not reliable source of information on shoreline evolution and a lack of historical monitoring data. Accurately identification of shoreline positions over a given period of time is a key to quantitatively and accurately assessing the beach erosion and accretion. The study is therefore to propose an innovative method of accurately shoreline positions for an analysis of coastal erosion and accretion in the Cua Dai estuary. The proposed technology of multitemporal remote sensing and digital evaluation model with tidal correction are used to analyse the changes in shoreline and estimate the rate of erosion and accretion. An empirical formula is, especially, exposed to fully interpret the shoreline evolution for multiple scales based on a limitation of satellite images during 1965 to 2018. The results show that there is a significant difference of shoreline shift between corrections and non-corrections of tidal. Erosion process tends to be recorded in the Cua Dai cape located in the Cua Dai ward, especially in the An Luong cape located in the Duy Hai commune with the length of 1050 m. Furthermore, it is observed that there is much stronger erosion in the north side compared with south side of Cua Dai estuary.


2007 ◽  
Vol 8 (2) ◽  
pp. 33 ◽  
Author(s):  
ABO BAKER.I. ABO ZED

This study evaluates the effect of prevailing dynamic factors on the sedimentation process in Damietta Harbour along the Nile delta coast of Egypt. The monitoring program spanned the period between 1978 and 1999 and included measurements of waves, currents and bathymetric profiles. The evaluation was based on determination of erosion and accretion rates, current regime, sediment transport, wave characteristics and wave refraction. Results revealed that the predominant wave direction from N-NW sector (86 %) throughout the year is responsible for generation of a longshore eastward current. Less frequent waves from the N-NE sector generate an opposing longshore westward current. The refraction pattern for the prevailing wave direction indicates that the harbour and its navigation channel are located within a divergence of wave orthogonal and in an accretion sediment sink area. The annual net rate of littoral drift on the western side of the harbour is about 1.43 * 105 m3 (accretion), while the annual net rate of littoral drift on the eastern side is about 2.54 * 105 m3 (erosion). Currents fluctuate tremendously in speed and direction, especially during the winter months. Hence, sediment transport takes place in offshore, eastward, and onshore directions. Progressive vector diagrams show that the largest near bottom offshore, onshore and easterly net drift occurs during summer, spring and winter respectively. The onshore sediment transport generated during spring and summer plays an important role in the redistribution of eroded sediments during the winter. The overall study of dynamic factors indicated that the harbour site is characterized by eastern, western, offshore and onshore sediment movements. Therefore, the north-south orientation of the navigation channel, with its depth greater than the surrounding area, interrupts sediment drift from different directions and reduces the current speed. Consequently, the sediments sink within the navigation channel from different directions. The sources of sediments contributing to the siltation process of the harbour and its navigation channels are mainly derived from the Rosetta promontory, Burullus beaches, Damietta promontory and from offshore and the dumping area.


Geology ◽  
2008 ◽  
Vol 36 (8) ◽  
pp. 599 ◽  
Author(s):  
Jean-Daniel Stanley ◽  
Thomas F. Jorstad ◽  
Maria Pia Bernasconi ◽  
Dennis Stanford ◽  
Margaret Jodry

Sign in / Sign up

Export Citation Format

Share Document