GPSW-7 WELL, Sample 29: Middle Cenomanian - Late/Upper Cenomanian, Egypt

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Equisetopsida - Cheirolepidiaceae
Classopollis brasilensis
0,5 rank
Dinophyceae - Gonyaulacales
Xiphophoridium alatum Sarjeant 1966
5-9 rank
Dinophyceae - Peridiniales - Peridiniaceae
Palaeohystrichophora infusorioides Deflandre 1936
1-4 rank
see common names

Geography
Country:Egypt State/province:north Western Desert
Coordinates: 30.0° North, 28.0° East (view map)
Paleocoordinates:9.8° North, 23.1° East
Basis of coordinate:estimated from map
Time
Period:Cretaceous Epoch:Late/Upper Cretaceous
Stage:Cenomanian 10 m.y. bin:Cretaceous 5
Key time interval:Middle Cenomanian - Late/Upper Cenomanian Pollen zone: Classopollis brasiliensis
Age range of interval:100.50000 - 93.90000 m.y. ago
Stratigraphy
Formation:Abu Roash Member:G
Local section:Abu Roash-G Local bed:1830-1833 m
Local order:top to bottom
Lithology and environment
Primary lithology:gray lithified calcareous mudstone
Secondary lithology:gray lithified calcareous "shale"
Environment:shallow subtidal indet.
Geology comments: The Bahariya Formation is conformably overlain by the Abu Roash G Member (middle/late Cenomanian) which does not witness any marked palynofloral or palynofacies changes from the underlying Bahariya Formation, except in its lower part, which contains high amounts of dinocysts suggesting a marine influence. The deposition of the Abu Roash G Member took place in a shallow marine setting (Barakat et al., 1980), based on microfacies analysis of the Cretaceous deposits in the north Western Desert. This finding was also supported by ostracodes and foraminifera identified from the same interval in the GPTSW-7 well (GPC, 1994). The Abu Roash G Member is located within the field V of the AOM–Phytoclast–Palynomorph ternary plot of Tyson (1993), corresponding to mud-dominated oxic shelf (Fig. 5A) and within the very high terrestrial/fresh-water influx field (Fig. 5B) of Roncaglia and Kuijpers (2006) ternary plot.
Taphonomy
Modes of preservation:soft parts,original sporopollenin
Size of fossils:microfossils
Collection methods and comments
Collection excludes:all microfossils
Collection methods:core,chemical
Reason for describing collection:biostratigraphic analysis
Metadata
Database number:140407
Authorizer:C. Jaramillo Enterer:G. Doria
Research group:paleobotany
Created:2013-03-09 06:35:46 Last modified:2013-03-08 13:35:46
Access level:the public Released:2013-03-09 06:35:46
Creative Commons license:CC BY
Reference information

Primary reference:
43920. S. El Beialy, H. S. El Atfy, M. S. Zavada, E. M. El Khoriby, and R. H. Abu-Zied. 2010. Palynological, palynofacies, paleoenvironmental and organic geochemical studies on the Upper Cretaceous succession of the GPTSW-7 well, North Western Desert, Egypt. Marine and Petroleum Geology 27:370-385 [C. Jaramillo/G. Doria/G. Doria]