Journal of Palaeogeography, (2015), 4, (3): 305-330 Available online at www.sciencedirect.com journal homepage: http://ees.elsevier.com ScienceDirect Vol. 4 No. 3 July 2015 古地理学报 英文版 （ ） HOSTED BY Lithofacies palaeogeography and sedimentology Sequence architecture of a Jurassic ramp succession from Gebel Maghara (North Sinai, Egypt): Implications for eustasy Ahmed Awad Abdelhady a, * , Franz Theodor Fürsich b a Geology Depart ment , Facult y of Science, Minia Universit y, 61519 Minia, Egypt b FG Paläoumwelt , Geozent rum Nordbayern der Universit ät Erlangen, Loewenichst rasse 28, D-91054 Erlangen, Germany Received 15 August 2014; accepted 5 January 2015 Available online KEYWORDS facies; sequence stratigraphy; ramp; extensional basin; Jurassic; Gebel Maghara; Egypt Abstract The Jurassic succession at Gebel Maghara, North Sinai, Egypt, represents a mixed carbonate-siliciclastic sequence. Combining information from both fossils and rocks allowed a plausible reconstruction of the depositional environments and of the basin topography. The Jurassic succession of Gebel Maghara was deposited on a ramp, and the architecture of the ramp facies was strongly controlled not only by sea-level changes but also by extensional tec- tonics in connection with rifting of the Tethys, North Gondwana. Seven tectonically modiied third-order sequences (DS 1-DS 7) have been recognized. The irst three sequences (DS 1-DS 3), ranging from the Toarcian to the Baj ocian, record sea invasion (intertidal to shallow subtid- al conditions) across an intracratonic area as a result of eustatic sea-level changes during a quiescent rift stage. The remaining sequences (DS 4-DS 7) relect open marine mid to outer ramp settings. Non-marine conditions around the Bajocian-Bathonian boundary, documented by caliche, represent the maximum regression of the sea. During an active extensional stage, horsts, which formerly acted as barriers separating the Maghara sub-basin from the main ocean, subsided. Subsequent rejuvenation and reactivation of faults shifted the homoclinal physiography of the ramp to a distally steepened ramp during the early Bathonian, creating a 200-m-thick deltaic wedge. Similar processes during the early Kimmeridgian created a cal- cirudite-calcarenite succession of slope origin. The diversity of the stratigraphic pattern and the epifaunal/ infaunal percentage of the macrofauna display a cyclic pattern which coincides more or less with the sequence stratigraphic architecture. * Corresponding author. E - mail address: alhady2003@yahoo.com. Peer review under responsibility of China University of Petroleum (Beijing). DOI: 10.3724/ SP.J.1261.2015.00082 ht t p:/ / dx.doi.org/ 10.3724/ SP.J.1261.2015.82 2095-3836/ Copyright © 2015, China University of Petroleum (Beij ing). Production and hosting by Elsevier B. V. This is an open access article under the CC BY-NC-ND license (http:/ / creativecommons.org/ licenses/ by-nc-nd/ 4.0/ ).