Geochemistry of Jizan shelf sediments, southern Red Sea coast of Saudi Arabia

Abstract

Surface sediments from the Jizan shelf, southern Red Sea, were analysed for grain size and mineralogical and elemental composition in order to establish their geochemical characteristics. Texturally, sediments are classified into sand and mud; the latter dominates the shelf. Grain size variability and mineralogical assemblages present in the sediments largely control the abundance and distribution of CaCO 3 , organic carbon content (OC) and the major and trace elements. Sand sediments are composed of carbonate material of marine origin and contain high concentrations of Ca, Mg and Sr. Mud sediments are relatively rich in OC and are characterised by high concentrations of Al, Fe, Ti, Mn, Cu, Cr, Co, Ni, V and Ba. Unlike the sand, Mg concentration in the mud sediments seems to be controlled by stronger contribution from non-carbonate material. Factor analysis is applied to identify the variables accounting for most of the variance in the mud sediment samples. Three factors are found to describe about 78% of the variance. The first factor which accounts for 41% of the total variance is the Fe and Mn oxides that reach the area through episodic flooding. The second and third factors are the mud (22%) and the mineralogy (15%) of the sediments, respectively.

New insights into geochemical behaviour in ancient marine carbonates (Upper Jurassic Ammonitico Rosso): Novel proxies for interpreting sea‐level dynamics and palaeoceanography

“…In the framework of the multi‐proxy approach used, the extraction of significant stratigraphic patterns from thousands of data points is performed through statistical methods (e.g. Chen et al ., ; Basaham, ; Dias et al ., ; Monien et al ., ). The use of a rigorous statistical framework, including linear correlations, principal component analysis, hierarchical cluster analysis and variogram computation allows for an integrated and quantitative assessment of the complete geochemical dataset.…”

Composition And Characteristic Of The Surficial Sediments In The Southern Corniche Of Jeddah, Red Sea Coast

“…The shallow water carbonate deposits comprise mainly of biogenic sand enriched in calcareous algae, coral debris, skeletons remain of molluscs, and foraminiferal tests (Bahafzallah and El-Askary, 1981;Behairy, 1984, 1986;Basaham, 2009;Al-Dubai, 2011;Bantan and Abu-Zied, 2014). Chemical and biochemical carbonate deposits also take place in the coastal hypersaline shallow areas (Winter et al, 1983;Ellis and Milliman, 1985;Basaham, 2009). Wright and Burchette (1996) reported that carbonate deposits are very frequent and consist of biogenic carbonate (detrital bioclastics and non-detrital calcareous organisms), peloids, coated grains (e.g., ooids), aggregates, lithified clastics and matrix (mud-grade carbonate).…”