An integrated remote sensing, petrology, and field geology analyses for Neoproterozoic basement rocks in some parts of the southern Egyptian-Nubian Shield.

The main objective of this study was to use deep learning, and convolutional neural networks (CNN), integrated with field geology to identify distinct lithological units. The Samadia-Tunduba region of the South Eastern Desert of Egypt was mapped geologically for the first time thanks to the use of processed developed CNN algorithms using Landsat 9 OLI-2, which were further enhanced by geological fieldwork, spectral measurements of field samples, and petrographic examination. According to previously published papers, a significant difference was observed in the distribution of rocks and their boundaries, as well as the previously published geological maps that were not accurately compatible with the nature of the area. The many lithologic units in the region are refined using principal component analysis, color ratio composites, and false-color composites. These techniques demonstrated the ability to distinguish between various igneous and metamorphic rock types, especially metavolcanics, metasediments, granodiorite, and biotite monzogranite. The Key structural trends, lithological units, and wadis affecting the area under study are improved by the principal component analysis approach (PC 3, 2, 1), (PC 2, 3, 4), (PC 4, 3, 2), (PC 5, 4, 3), and (PC 6, 5, 4) in RGB, respectively. The best band ratios recorded in the area are recorded the good discrimination (6/5, 4/3, and 2/1), (4/2, 6/7, and 5/6), and (3/2, 5/6, and 4/6) for RGB. The classification map achieved an overall accuracy of 95.27%, and these results from Landsat-9 data were validated by field geology and petrographical studies. The results of this survey can make a significant difference to detailed geological studies. A detailed map of the new district has been prepared through a combination of deep learning and fieldwork.

Evaluation of sediment quality for heavy metal(loid)s contamination and health risk assessment in the Gulf of Suez, Egypt.

The Gulf of Suez faces challenges related to contamination, primarily due to industrial, tourism, and shipping activities along its shores. This study aims to record the distribution, concentration, and potential environmental and health risk impacts of heavy metal(loid)s (HMs) in 30 surface sediment samples collected from Ras Sidr coastline, Gulf of Suez. Various contamination and health indices were employed for this study. The average concentrations of HMs (µg/g) were ranked as follows: Fe (3472), Mn (103.3), V (10.41), As (7.94), Cr (6.00), Zn (5.31), Ni (2.94). The spatial distribution of HMs indicated an increase in Mn, Zn, As, and V levels toward the southern part of the study area, potentially linked to the proximity of manganese quarries and their metal association at Abu Zenima. Contamination indices revealed moderately severe enrichment with As, minor enrichment with Mn, and no enrichment for the remaining HMs. Multivariate analysis suggested a natural origin for Cr, Fe, Mn, Ni, Zn, and V, while As were likely anthropogenic. Values of hazard index (HI) for HMs in both adults and children followed the descending order of As > Fe > Cr > V > Mn > Ni > Zn. However, all HI values were below 1.0, indicating no significant non-carcinogenic risk for individuals along the Ras Sidr coastline. 19 samples exhibited lifetime cancer risk (LCR) values exceeding 1 × 10-4 for As in children, suggesting potential carcinogenic risks. LCR values for As in adults and Cr in adults and children ranged from 1 × 10-5 to less than 1 × 10-6, indicating acceptable or tolerable levels of carcinogenic risk and no significant threats to health.

Potential contamination and health risk assessment of heavy metals in Hurghada coastal sediments, Northwestern Red Sea.

Throughout the year, people flock to the Red Sea's shoreline for tourism and fishing. The current study aims to document heavy metal contamination and human health assessment in 30 surface sediment samples collected along the Hurghada shoreline in Egypt. To estimate sediment contamination, the pollution index (PI), pollution load index (PLI), degree of contamination (Cdeg), and Nemerow integrated pollution index (NIPI) were calculated, while the chronic daily intake (CDI), hazard index (HI), cancer risk (CR), and total lifetime cancer risk (LCR) were determined on both adults and children via ingestion, dermal, and inhalation pathways. The HM averages (µg/g dry weight) were in the following order: Fe (345.70) > Mn (49.36) > Pb (41.98) > Zn (7.47) > Ni (1.73) > Cu (1.23) > Co (1.09) > Cd (0.14). Pollution indices found that Hurghada coastal sediments were moderately polluted with Pb but not with the other HMs. The average CDI values were in the descending order of ingestion > dermal > inhalation pathways, and the average CDI values on children were higher than those on adults. The hazard index (HI) for adults and children was Pb > Ni > Cd > Fe > Mn > Co > Cu > Zn, and all values were <1.0, showing that these HMs had no substantial non-carcinogenic impacts on the human body. LCR results show that children have greater values than adults. LCR values in adults were lower than 1 × 10-6, indicating no substantial health concerns, while in children they ranged from 1 × 10-6 to 1 × 10-4, indicating no significant risk to human health.

Influence of seawater intrusion and heavy metals contamination on groundwater quality, Red Sea coast, Saudi Arabia.

Groundwater samples were collected from 115 boreholes and dugwells to document the influence of seawater intrusion and heavy metals contamination on groundwater quality of the Al Qunfudhah region along the Red Sea coast, Saudi Arabia. The groundwater quality index (GWQI), metal index (MI), and heavy metal pollution index (HPI) were calculated and multivariate analyses were conducted. pH, EC, TDS, Cl-, HCO3-, SO42-, NO3-, NO2-, PO43-, SiO2, F-, NH4+, Ca2+, Mg2+, Na+, K+, B, Ba, Cd, Cr, As, Ni, Pb, Se, Sb, Hg, Cu, and Zn were analyzed and interpreted. The average values for TDS, Ca2+, Mg2+, Na+, K+, Cl-, HCO3-, SO42-, B, and Se were greater than the permissible limit of WHO standards for drinking water. Piper plots indicated three types of groundwater facies, Na-K-SO4-Cl (72.50%), Ca-Mg-So4-Cl (25.50%), and Na-K-CO3-HCO3 (2%). Based on GWQI, MI, and HPI, approximately 37-70% of the groundwater samples fell under poor quality to unsuitable waters (strongly to severely affected), especially in the western part along the Red Sea coast. This proven the role of seawater intrusion through the NE-SW fault system, dissolution/precipitation of carbonates, silicates, fluorite, and gypsum, as well as anthropogenic factors in increasing the concentrations of heavy metals and controlling the chemistry and quality of the groundwater in the study area. These findings provide an important information on heavy metals pollution in coastal aquifer with seawater intrusion along the Red Sea.

Evaluation of heavy metal contamination and groundwater quality along the Red Sea coast, southern Saudi Arabia.

To evaluate the heavy metal contamination and groundwater quality in southern Saudi Arabia, 105 groundwater samples were analyzed for EC, pH, TDS, major ions (NO3-, Cl-, HCO3-, SO42-, F-, Ca2+, Mg2+, Na+, and K+), and heavy metals (Fe, Li, As, B, Al, Cr, Cu, Mo, Ni, Se, Sr, V, Zn, and Mn). Groundwater quality index (GWQI), degree of contamination (Cd), heavy metal pollution index (HPI), ecological risks of heavy metals (ERI), salinity hazard (EC), sodium adsorption ratio (SAR), sodium percentage (Na%), and Kelly's ratio (KR) were calculated and compared, and multivariate statistical techniques were applied. The results revealed that the major cations and anions followed the orders of Na+ > Ca2+ > Mg2+ > K+ and Cl- > SO42- > HCO3- > NO3- > F-, respectively. The maximum values of As, Mn, Cr, Ni, Se, and Zn were above the permissible limits for drinking water purposes. Pollution indices indicated that 20 to 52% of the groundwater samples were suitable for agricultural and domestic purposes. The unsuitable samples were distributed mostly in the western part along the Red Sea coast. Multivariate statistical analyses revealed that the dissolution of halite and gypsum (in sabkha deposits), carbonates, and the agricultural activities were the possible sources of the major cations and anions, and heavy metals in the study area.

Contamination and ecological risk assessment of the Red Sea coastal sediments, southwest Saudi Arabia.

The level of heavy metals (HMs) in coastal sediments has attracted the environmental researchers due to their persistence, abundance, biomagnification and toxicity. The present study was conducted to assess the contamination and ecological risk assessment of HMs in Jazan coastal sediments, Red Sea, Saudi Arabia utilizing pollution indices and multivariate statistical analyses. A total of 32 surface samples were collected for Cu, Sb, Zn, Cr, Cd, Pb, Fe, Co, Ni, Al, and total organic matter analysis using an atomic absorption spectrophotometer. The results indicate the following descending order of metal concentrations: Al > Fe > Cr > Cu > Zn > Ni > Co > Pb > Cd > Sb. Average level of Cd is significantly higher than those from many neighboring and worldwide coastal sediments; and recorded very severe enrichment, severe contamination and very high risk in the investigated sediments. The pollution indices and statistical analyses revealed that proportion of Zn, Fe, Ni, Cr, Al, Cu, Sb and Pb were formed from lithogenic sources of weathering Quaternary units and atmospheric deposition. Most of the Cd, Sb, and Pb levels were derived from anthropogenic sources of industrial, agricultural, and fishing activities. The higher contribution of organic matter may be attributed to the mangrove roots and organic fertilizers; and played a key role in adsorbing, transferring and accumulating of elements.

Spatial distribution and ecological risk assessment of the coastal surface sediments from the Red Sea, northwest Saudi Arabia.

To assess the spatial distribution and ecological risk assessment along the Red Sea coast, Saudi Arabia, 30 samples were collected for aluminum, chromium, copper, zinc, cadmium, lead, mercury, iron, cobalt, nickel and organic matter analysis. The descending order of metal concentrations was Al > Fe > Cr > Cu > Zn > Ni > Co > Pb > Hg > Cd. Average values of enrichment factor of Hg, Cd, Cu, Co, Cr, Ni, Pb and Zn were higher than 2 (209.50, 25.52, 20.36, 9.62, 7.28, 6.52, 6.21 and 6.07 respectively), which means anthropogenic sources of these metals. The average levels most of the studied metals were lower than those of the background shale and the earth crust and those recorded along most worldwide coasts, while the average values of zinc, copper, cobalt and nickel were higher than the values recorded from the Red Sea coast, the Gulf of Aqaba and some Caspian Sea coasts. The Duba bulk plant-Saudi Aramco, Duba refinery station and the tourist resort were the possible anthropogenic sources of pollutants in the southern part of the study area; and the landfilling, cement factory and Duba port and shipment operations in the central part, while the landfilling resulting from construction of the green Duba power plant and crowded fish boats were the possible sources in the northern part.

Assessment of sediment quality using different pollution indicators and statistical analyses, Hurghada area, Red Sea coast, Egypt.

Thirty bottom sediment samples were collected from northern Hurghada coast, Red Sea, Egypt to evaluate the level of anthropogenic pollutants, using enrichment factor (EF), potential ecological risk index (PERI), soil pollution index (SPI), potential contamination index (Cp) and multivariate statistical analysis (correlation analysis, principal component analysis, and hierarchical cluster analysis). Fe, Mn, Zn, Pb, Ni, Cu, Co and Cd were analyzed by Atomic Absorption Spectrophotometer. Results indicated that the average values of Pb and Cd were greater than the ones recorded from many other worldwide coastal areas. The studied sediments are extremely severe enrichment with Pb and Cd (EF > 50), severe enrichment with Zn (EF = 10-25), very high risk with Cd (PERI ≥ 320), high risk with Pb (160 ≤ PERI ˂ 320), highly contaminated with Pb (SPI > 3), a severe contamination with Pb (Cp > 3). The accumulation of pollutants is associated with the muddy and fine sediment; especially the studied area is a semi-closed bay, characterized by long time of water retention. Possible sources of metals pollution in the studied area are shipment operations and anticorrosive and antifouling paints, dredging and land filling, municipal wastewater from tourist centers and fishermen cargo boats.

Spatial distribution and metal contamination in the coastal sediments of Al-Khafji area, Arabian Gulf, Saudi Arabia.

To document the spatial distribution and metal contamination in the coastal sediments of the Al-Khafji area in the northern part of the Saudi Arabian Gulf, 27 samples were collected for Al, V, Cr, Mn, Cu, Zn, Cd, Pb, Hg, Sr, As, Fe, Co, and Ni analysis using inductively coupled plasma-mass spectrometer (ICP-MS). The results revealed the following descending order of the metal concentrations: Sr > Fe > Al > As > Mn > Ni > V > Zn > Cr > Cu > Pb > Co > Hg > Cd. Average levels of enrichment factor of Sr, As, Hg, Cd, Ni, V, Cu, Co, and Pb were higher than 2 (218.10, 128.50, 80.94, 41.50, 12.31, 5.66, 2.95, 2.90, and 2.85, respectively) and that means the anthropogenic sources of these metals, while Al, Zn, Cr and Mn have enrichment factor less than 2, which implies natural sources. Average values of Sr, Hg, Cd, Cr, Ni, and As in the coastal sediments of Al-Khafji area were mostly higher than the values recorded from the background shale and earth crust and from those results along coasts of the Caspian Sea and the Mediterranean Sea. The highest levels of Cu in the northern part of the studied coastline might be due to Al-Khafji desalination plant, while levels of Al, Ni, Cr, Fe, Mn, Pb, and Zn in the central part may be a result of landfilling and industrial sewage. The highest levels of As, Cd, Co, Cu, Hg, and V in the southern part seem to be due to oil pollutants from Khafji Joint Operations (KJO). The higher values of Sr in the studied sediments in general and particularly in locality 7 could relate to the hypersalinity and aragonitic composition of the scleractinian corals abundant in that area.