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A large proportion of the world's population lives in coastal areas. These zones play a vital role in the socioeconomic aspects of coastal communities. The evolution of shoreline along the zones is of great importance to scientists, and engineers as well as coastal management. This research aims to assess and understand the dynamics of shoreline along the Red Sea coast between Al Lith and Ras Mahāsin, using medium-resolution satellite imagery over 34 years (1984–2018) as well as to predict futuristic changes in the shoreline position until 2038. The tasseled cap transformation tools in ArcGIS 10.2 are used to extract shoreline position for seventh intervals time. These shorelines are analyzed by the digital shoreline analysis system in four statistical functions, namely (EPR, LRR, NSM, and LMS). The endpoint rate is used to predict futuristic shoreline positions. The results reveal that the evolutions of shoreline in the form of erosion and accretion patterns, as surface area exceed 12.3 and 0.89 km2, respectively. The evolution rates were classified based on LRR into five classes: [i.e., − 11.84 to − 7.85 (very high erosion), − 7.85 to − 4.17 (moderate erosion), − 4.17 to 0.00 (low erosion), 0.00 to 1.28 (low accretion), and 1.280 to 14.44 (high accretion)]. These changes are attributed to the impact of the extreme wave action and the littoral drifts of sediments by longshore currents. The prediction model reveals that a large portion of the coastal zone is vulnerable to a high rate of shoreline disintegration.

The stratigraphy of the late Holocene shallow subsurface coastal sediments, North Al-Wajh, Saudi Arabia was investigated to reconstruct the environmental evolution of the area in relation to sea-level changes. Five shallow cores (1.1 to 2.2 m long) were collected from the intertidal flat bordering the Dumaygh Lagoon, and the mouths of wadis Antar and Haramil. The cores exhibit siliciclastic-dominated sediments, in some parts containing reworked calcareous shell fragments of bivalves, gastropods and coral remains. The sediments were analyzed for grain size, loss on ignition (LOI), CaCO3 content, and bulk mineralogy. Mineralogically, the sediments were dominated by siliciclastic minerals (quartz, plagioclase, feldspars, and hornblende) followed by low Mg-calcite (LMC), high Mg-calcite (HMC) and aragonite. In addition, traces of mica, amphiboles, clay minerals, and dolomite were recognized. There is a slight lateral variation in the relative abundance of aragonite and high Mg calcite (HMC), particularly at the base of cores. The results provide a simple scenario for the late Holocene Northern Red Sea coastal evolution. Two vertically stacked sedimentary facies were recognized from the cores; grey mud-dominated lagoonal/bayfill at the base and yellowish-brown sand-dominated intertidal flat at the top. The vertical facies stacking suggests a forestepping pattern or progradational sequence possibly attributed to the late Holocene relative sea-level fall.

The Al-Salam Lagoon is one of the recreational sites along the Jeddah coast, showing the environmental impacts of urbanization along the coast. A sediment core (220 cm) was collected from the intertidal zone to evaluate the heavy metals (Fe, Mn, Cr, Ni, Cu, Zn, and Pb) and geochemical indices (contamination factor, geo-accumulation index, and pollution load index). In the organ-ic-rich muddy sediments (0–100 cm), there is a high metals content and a pollution load index of ~3, indicting anthropogenic impacts with high Cu contamination (CF:12) and moderate Fe, Mn, Cr, Ni, Zn, and Pb contamination (CF: &lt, 3). The organic matter and heavy metals washed through surface run-off from the land and deposited as urban waste. Down the core, consistent metals concentration, CF, and Igeo trends indicate a common pollutant source and pollution load variations over time. In the sediment section (70–40 cm), a high organic matter, metal concentration, CF, Igeo, and PLI value (≥5) suggest an uncontrolled pollution load. The decreased and stable trends of environmental indicators toward surface sediments suggest measures taken to control the pollution along the Jeddah coast. Below 110 cm, the carbonate-rich sediments have low organic matter and metals, showing an unpolluted depositional environment. The negative geo-accumulation index implies a geogenic source and indicates no anthropogenic impacts as inferred from low (~1.0) CF and PLI.

Late Quaternary paleoenvironments are of particular interest to understand how the Earth System’s climate will respond to the undramatic changes during this period, compared with the broader glacial-interglacial variations. In this study, a shallow sediment core (2.84 m long) retrieved from the Red Sea coastal zone in northern Ghubbat al Mahasin, south of Al-Lith, Saudi Arabia, is used to reconstruct the mid-Late Holocene paleoenvironments and sea level based on a multiproxy approach. Remote sensing data, sedimentary facies, benthic foraminiferal assemblages, δ18O and δ13C stable isotopes, elemental composition and14C dating were utilized. The stratigraphy of the core shows three distinctive depositional units. The basal pre 6000 year BP unit consists of unfossiliferous fine to medium sand sharply overlain by black carbonaceous mud and peat, suggesting deposition in a coastal/flood plain under a warm and humid climate. The middle unit (6000-3700 year BP) records the start and end of the marine transgression in this area. It consists of gray argillaceous sand containing bivalve and gastropod shell fragments and a benthic foraminiferal assemblage attesting a lagoonal or quiet shallow marine environment. The upper unit (

The present work is related to mineralogy and geochemistry of sedimentary successions of the modern Red Sea coastal plain at the mouth of Wadi Al-Hamd, Northern Saudi Arabia. It identifies the provenance, weathering effect, and paleoenvironment of the area. The mineralogical composition is dominated by quartz, plagioclase, and trace of feldspars, clay minerals, mica, and hornblende. Additionally, traces of non-detrital minerals including high and low Mg calcite, dolomite, halite, and anhydrite were locally detected. Four chemo-facies, dominated by three associations of element groups linked with detrital minerals, grain size properties, and biogenic products were recognized. The mineralogical and geochemical indices showed that sediments were derived from the intermediate igneous rocks at active continental margin and continental island arc settings. Weathering indices showed that the sediments were poorly weathered, consistent with the arid-to-semi-arid climate of the area. The spatial and vertical variations of mineralogical and chemical composition reflect variation depositional environments, hydraulic sorting, and the influence of coastal processes.

The southern coastal areas of Java are highly vulnerable areas of earthquake hazard because they located 200 km from the southern Java subduction zone. This zone is an active seismicity area, resulting in many tectonic earthquakes caused by collisions and shift between the plates. This shift when it occurs under the sea surface with a large power intensity can lead to a tsunami. This research conducted to identify the extent of agricultural land (AL) damaged by the tsunami for disaster risk management and mitigation. Numerical modelling was performed to determine the run-up height of the tsunami through numerical data. This model was designed using the worst-case scenario. The tsunami inundation model analysed from the coming wave (run-up) with a height of 30 m. This model used scenarios of tsunami run-up height in a coastline, coarse coefficient and slope. The data extracted using remote sensing (RS) data was the slope obtained from the ASTER image GDEM data, the agricultural land productivity data obtained using NDVI vegetation index transformation and field data on productivity, and tsunami hazard analysis with various altitude scenarios using run-up model impact on existing AL conditions. The elevation-data was obtained from the 15 m ASTER image data (GDEM) that was reclassified into a slope class map. The risk of destruction of AL based on wave height extracted by using RS data generated rice risk loss index of AL of 190.5071 tons for a height of 1 m, 1851.522 tons for a height of 5 m, 7402.71 tons for a height of 10 m, 10776.47 tons to a height of 15 m, 11823.9 tons for height 20 m, and 11824.27 tons to a height of 30 m.

Jazan city is a fast-growing coastal city in the southern part of Saudi Arabia, Red Sea. Recently, it has encountered quick industrial development activities. To monitor these activities, the changes in coastal zone morphology explore over the last 30 years (1987–2017) using GIS and remote sensing techniques. Four satellite images (TM and ETM) acquired during these intervals were performed. Furthermore, a development and growth of the city were created based on direct digitizing from Google Earth Pro to identify the extension and expansion of the area of study during this period. The magnitudes of erosion, deposition, and landfilling at differential scales through the period of study were determined using photo-interpretation on the changes of surface area and the extension of the city landward. The results illustrated remarkable changes and shifting of shoreline seaward along the coast and extending of dwelling zone in the city. Erosion and accretion take place mostly in the earlier interval (1987–2000) in some parts of the coast followed by landfilling occurring in the northern and middle parts of the coastal area in the interval (2000–2013). However, the magnitudes were different from interval to interval. The relative changes were 14.33, 58.56, and 27.11 % at the periods from 1987–2000, 2000–2013, and 2013–2017, respectively. However, dwelling zone extended dramatically from 23.31 km2 in 1987, to 25.32 km2 in 2000, 63.37 km2 in 2013, and to reach 67.90 km2 in 2017. These changes probably attributed to human activities in the coastal area due to construct a new economic city in the northern part during the period between 2003 and 2013 along with different socio-economic activities. The tidal flat in front of the city is shrunk due to this landfilling. This landfilling has been destructed a wide range of mangrove ecozones and possibly impacted the biotics in the area.

This work discusses the composition and characteristic of the surficial sediments in the southern corniche of Jeddah, Saudi Red Sea coast, in an attempt to infer the surficial distribution pattern of minerals and provenance of sediments. Twenty-six superficial sediments samples were collected from backreef and forereef areas and were analyzed for grain size, CaCO3 content, and mineralogy. The textural of grain size range from gravel to mud fraction. The mud-dominated substrates (

This study describes the subsurface sedimentary facies of a modern Red Sea coastal plain at the mouth of Wadi Al-Hamd, northern Saudi Arabia, in an attempt to infer the influence of aridity and limited tidal range on facies characteristics. The study provides criteria to delineate the fluviomarine transition in a setting where tidal signatures and other marine influences are weak. Six manually collected cores (1.4 to 1.75 m long) from the channels at the wadi mouth, beach ridge, intertidal flat, strandplain, and supratidal flat enabled the identification of 23 sedimentary facies. The sediments displayed rapid and tremendous variability in facies both within and among cores. They were deposited generally under low energy conditions occasionally punctuated by short-lived high energy events. The sediments in the channel exhibit features characterizing deposition under an arid and semiarid climate, such as rapid and intermittent discharge and short-lived rapidly abandoned channels. The sediments and depositional settings on both sides of the wadi mouth are different. A low gradient intertidal flat influenced by wave and tidal processes develops to the south, whereas a relatively high energy wave dominated strandplain occurs to the north. The deposition in the supratidal flat was accomplished by a short-lived high energy washover event. The facies stacking pattern indicates that the depositional systems are in a state of transgression, with a regime of gradually increasing accommodation possibly during the rising of relative sea level and diminishing of sedimentation. The turnaround from regressive to transgressive stage that coincides with the fluviomarine transition in channel fill deposits is placed at a level of increased soft sediment deformation because the tidal influence is weak in this microtidal setting. Though the plane view shows a deltaic shoreline, the depositional system is interpreted as estuarine. The findings of this study can be applied to similar recent and ancient settings.