Diagenesis and pervasive dolomitization of pre- and post evaporite shallow marine carbonates, Ras Banas Peninsula, Red Sea Coast, Egypt

• Published in: Arabian journal of geosciences Vol. 15; no. 16
• Main Authors: Abou Elmagd, Kamal, Matsumoto, Ryo
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 2022; Springer Nature B.V
• Subjects: Basement rock; Cambrian; Carbonates; Cathodoluminescence; Clastics; Climate change; Crystals; Diagenesis; Dolomitization; Earth and Environmental Science; Earth science; Earth Sciences; Evaporites; Isotopes; Limestone; Miocene; Original Paper; Oxygen isotopes; Petrographic microscopy; Quaternary; Sea level; Sea level changes; Sequencing; Spectral analysis; Tectonics; Red Sea; Diagenesis; Geochemistry Miocene; Dolomite; Stable isotopes; Evaporite
• ISSN: 1866-7511; 1866-7538
• DOI: 10.1007/s12517-022-10648-8

The present study deals with diagenesis and dolomitization modeling of Middle Miocene – Quaternary sedimentary sequence outcropped at Ras Banas Peninsula, Egyptian Red Sea Coast. This sequence is comprising successively overlapped clastics, carbonates, and evaporites attaining 254 m total thickness resting on the Pre-Cambrian basement rocks in the Peninsula. Diagenetic history and dolomitization were carefully investigated using several techniques including petrographic microscope, XRD, SEM, cathodoluminescence, atomic absorption, and isotopes of oxygen and carbon. The conspicuous phenomena is the pervasive dolomitization of directly pre- and post evaporite limestone components. These dolomites are mostly nonstochiometric, poorly to moderately ordered crystals. Based on all the results obtained from this study, the dolomitization processes of Ras Banas Peninsula are the result of complex geologic setting, paleo-climate changes, tectonic activity, and sea-level fluctuations. The proposed graphic model describes dolomitization mechanism which refers to mixed meteoric-hypersaline water environments.