Several small echinoid faunules are recorded from the Umbaraaf and Khadrafi members of the Dhalqut Formation, the upper unit of the Albian–Turonian Qamar Group in the eastern part of the Jeza-Qamar ...Basin of Dhofar (southern Oman). In all, 11 species, in nine (sub)genera, are described: Arabicodiadema dhofarense (Roman), Arabicodiadema romani Smith and Jagt n. sp., Heterodiadema libycum (Desor, in Agassiz and Desor), Emiratia raskhaimahensis Ali, Orthopsis miliaris (d’Archiac), Pedinopsis (P.) sphaerica Smith, Simmons and Racey, Pedinopsis (Sinaiopsis) sinaica (Desor, in Agassiz and Desor), Goniopygus dhalqutensis Smith and Jagt n. sp., Coenholectypus excisus (Desor, in Agassiz and Desor), Coenholectypus larteti (Cotteau) and Pliotoxaster dieneri (de Loriol). These novel echinoid data suggest that the Umbaraaf Member extends into the Cenomanian, thus supplementing previous biostratigraphical dating based on foraminifera. The echinoid fauna also suggests correlation of the Umbaraaf and Khadrafi members with strata such as the Natih Formation in north-central Oman, the Mauddud Formation of the northeastern United Arab Emirates, the Galala Formation of the North-Eastern Desert of Egypt and the Wasia Formation of central Saudi Arabia.
A satellite remote sensing technique is demonstrated for generating near surface geological structure data. This technique enables the screening of large areas and targeting of seismic acquisition ...during hydrocarbon exploration. This is of particular advantage in terrains where surveying is logistically difficult. Landsat Thematic Mapper (TM) data and a high resolution digital elevation model (DEM), are used to identify the map outcropping horizons. These are used to reconstruct the near surface structure. The technique is applied in Central Yeman which is characterized by a 'layer-cake' stratigraphic section and low dipping terrain. The results are validated using two-dimensional seismic data. The near surface map images faults and structure not apparent in the raw data. Comparison with the structure map generated from two-dimensional seismic data indicates very good structural and fault correlation. The near surface map successfully highlights areas of potential closure at reservoir depths.
The Mesozoic basins of Yemen have a multiphase history of rift development. Sediments of the ‘Furt Formation’ were deposited as a result of a second, discrete phase of rift activity during the ...Hauterivian to Barremian and unconformably overlie older deposits (A. C. Ellis, H. M. Kerr, C. P. Cornwell and D. O. Williams, 1996, Petroleum Geoscience2, 29–42). The name is taken from the suggested type well, AI Furt-1, where the unit reached its maximum drilled thickness to date, in the Jeza-Howarime Basin. The lithology in the type well predominantly comprises calcareous mudstones with subordinate carbonates. In western Yemen and more marginal settings, the ‘Furt Formation' is dominated by arenaceous facies. Biostratigraphic analysis suggests that the upper and lower limits of the 'Furt Formation' are bounded by stratigraphic breaks. Regional seismic lines suggest and biostratigraphy confirms the extension of the 'Furt Formation' into basin margin areas and other rift basins, supporting the case for regarding the Furt section as a formation in its own right.
The Qishn Formation has been divided on a tripartite basis. The oldest units are the ‘Clastic’ and ‘Lower Carbonate Members’ which are lateral facies and age equivalents. The ‘Clastic Member’ is found in the west of Yemen while the ‘Lower Carbonate Member’ is best developed in the east. The transition between the two is seen in the Jeza-Howarime Basin. The middle unit, the ‘Shale Member’, is a regionally extensive mudstone facies thought to relate to a maximum flooding event. The youngest unit, the 'Carbonate Member', comprises a limestone sequence. The Qishn Formation is unconformably overlain bythe clastics of the Harshiyat Formation and in the extreme east of the Yemen by the carbonates of the Fartaq Formation. The Qishn Formation represents a transition from a rift to a post rift-phase (Ellis et al., 1996).
