6 M.K. HOWARTH AND N.J. MORRIS 



Table 2 Ammonite zones of the Callovian to Berriasian Stages in the Tethyan Province, and dates of the formations in Wadi Hajar (zones in the Callovian 

 and Oxfordian Stages are based on Arkell (1956), Mouterde & Enay (1971: 16-21) and Cariou & Hantzpergue (1997: 80, 84, 362), those in the 

 Kimmeridgian to Berriasian Stages on Howarth (1992: 599-601)). The horizons of dateable ammonite faunas in Yemen are shown by asterisks (*). 



STAGES 



AMMONITE ZONES 



MEMBERS 



FORMATIONS 



BERRIASIAN 



Fauriella boissieri 

 Timovella occitanica 

 Pseudosubplanires euxinus 



* Mintaq 



* 



HAJAR 



TITHONIAN 



U 



Durangites 



Micracanthoceras microcanthum 



* 



^ Arus 



L 



Micracanthoceras ponti 

 Semiformiceras fallauxi 

 Semiformiceras semiforme 

 Neochetoceras darwini 

 Hybonoticeras hybonotum 



y///////////A 



Disconformity/unconformity // 



*Kilya 



* 



NAIFA 



KIMMER- 

 IDGIAN 



U 



Hybonoticeras beckeri 

 Aulacostephanus eudoxus 

 Aspidoceras acanthicum 



* 

 *Billum 



* 



L 



CrussoUceras divisum 

 Ataxioceras hypselocyclum 

 Sutneria platynota 



OXFORDIAN 



U 



Subnebrodites planula 

 Epipeltoceras bimammatum 

 Dichotomoceras bifurcatum 





* 

 MADBI 



* 



M 



Gregoryceras transversarium 

 Perisphinctes plicatilis 



L 



Cardioceras cordatum 

 Quenstedtoceras mariae 



CALLOVIAN 



U 



Quenstedtoceras lamberti 

 Peltoceras athleta 



* 

 SHUQRA 



M 



Erymnoceras coronatum 

 Reineckeia anceps 



L 



Sigaloceras calloviense 

 Proplanulites koenigi 

 MacrocephaUtes herveyi 



BATHONIAN 





KOHLAN 



the Jebel Madbi section, with the Hmestone sequence (the Billum 

 Member) sandwiched between two marl sequences, led to the 

 proposal of the term Timurah Member in the explanation of the Bir 

 Ali/Balhaf map (D-39-61/73) for the development of this middle 

 limestone (the Billum Member) in the area around Jebel Timurah 

 and Wadi Timurah, approximately half way between Jebel Madbi 

 and Jebel Billum. We have not seen the type section or a formal 

 description of the Timurah Member, so we do not adopt this term in 

 preference to Billum Member. 



LOCALITIES IN WADI HAJAR 



Fig. 1 shows the location of Wadi Hajar and the main geological 

 sections examined in relation to Mukalla and the surrounding area in 

 southern Yemen, and also a more detailed map of the area in Wadi 

 Hajar between Al Ma'abir and Wadi Arus. The series of formations 

 and members in the Jurassic and Lower Cretaceous of Wadi Hajar 

 that are recognized here are shown in the right hand column of Table 

 1. Of these, the Hajar Formation and its two members, and the two 

 members of the Naifa Formation, are newly proposed in this paper. 

 A general distribution and correlation diagram for the Jurassic and 



