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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 evolution.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 tectonics in connection with rifting of the Tethys,North Gondwana.Seven tectonically modified thirdorder sequences(DS 1-DS 7) have been recognized.The first three sequences(DS 1-DS 3),ranging from the Toarcian to the Bajocian,record sea invasion(intertidal to shallow subtidal 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) reflect 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 calcirudite-calcarenite succession of slope origin.The diversity and the epifaunal/infaunal percentage of the macrofauna display a cyclic pattern which coincides more or less with the sequence stratigraphic architecture.