Stable isotopic composition of carbonate-cemented recent beachrock along the Mediterranean and the Red Sea coasts of Egypt

Unraveling cementation environment and patterns of Holocene beachrocks in the Arabian Gulf and the Gulf of Aqaba: stable isotope approach

“…5). d 18 O VPDB and d 13 C VPDB val ues of beachrocks from the Gulf of Aqaba fall within the range of mod ern beachrock in the Red Sea (Holail and Rashed, 1992). The Ara bian Gulf beachrocks show high d 18 O VPDB and d 13 C VPDB val ues com pared to other beachrocks (e.g., Red Sea and Med i ter ra nean; Fig.…”

“…Car bon ate min er als are pre cip i tated from ground wa ter in the zone be tween high and low tide level, and also may be aided by the ac tiv ity of mi cro or gan isms, such as bac te ria, that in habit the beach close to the wa ter ta ble and may in crease the pH of the pore wa ters and thus fa cil i tate carbon ate pre cip i ta tion (Bird, 2011). Beachrocks, in many instances, ex pe ri ence rapid ce men ta tion pro cesses (Holail and Rashed, 1992;Kneale and Viles, 2000). For ma tion of beachrocks is also as sisted by high evap o ra tion, which causes up ward move ment of wa ter and dis solved car bon ate min er als in the beach sand (Stoddart and Cann,1965).…”

“…De spite the dif fer ent ce men ta tion pro cesses and prod ucts, there is one com mon im por tant fac tor in beachrock for ma tion; ce men ta tion com monly oc curs within the intertidal zone (Bricker, 1971;Spurgeon et al, 2003). Beachrocks have been ex ten sively stud ied in many re gions in the world, such as on the coast of the Red Sea (e.g., Holail and Rashed, 1992;Ghandour et al, 2014), the Black Sea (Erginal et al, 2012(Erginal et al, , 2013, Florida (e.g., Spurgeon et al, 2003), the Med i ter ra nean (e.g., Alexandersson, 1972;El-Sayed, 1988), Cen tral Amer ica and the Ca rib bean (e.g., Beier, 1985), In dia (Kumar et al, 2000(Kumar et al, , 2012, the Ara bian Gulf (e.g.,Tay lor and Illing, 1971), Ha waii (Meyers, 1987), Aus tra lia (e.g., Chivas et al, 1986) and Scot land (e.g., Kneale and Viles, 2000). Beachrocks, a com mon fea ture of the east ern and north western coast lines of Saudi Ara bia, have been sub ject of a large num ber of mod ern coastal stud ies be cause of their func tion in the in ter pre ta tion of coastal dy nam ics (Chaves and Sial, 1998) and their im por tance as an in di ca tor of past sea level (Spurgeon et al, 2003).…”

“…Es pe cially in arid re gions, evap o ra tive ar eas dem on strate sur face wa ter 18 O en rich ment (Cooke and Rohling, 2003). Other sup port ing ev i dence is the ab sence of skel e tal struc tures within the ce ments, sug gest ing that the Arabian Gulf beachrock ce men ta tion was most prob a bly caused by Field of In dia beachrocks is from Kumar et al (2000); fields of beachrocks of the Gulf of Aqaba, Red Sea and the Med i ter ra nean are from Holail and Rashed (1992); field of beachrock of the Med i ter ra nean coast is from Alexandersson (1972); field of beachrocks from French Poly ne sia is from Neumeier (1999) …”

Mineralogical and geochemical compositions of modern bivalve shells from the Mediterranean coast of Egypt

“…The sediments which yielded and are associated with these shells· are postulated to have been deposited within marine settings (Holail and Rashed, 1992). Salinity is about 39 .2%o and not significantly different from one site to another.…”