Contribution to the scleractinian corals of Hanifa Formation, Upper Jurassic, Jabal Al-Abakkayn, central Saudi Arabia

Journal Article

مستخلص المنشور

Eighteen scleractinian coral species belonging to 13 genera, 8 families and 4 suborders have been identified from the lower
and upper parts of the Upper Jurassic (Oxfordian) Hanifa Formation at Jabal Al-Abakkayn, central Saudi Arabia.
Actinastrea bernensis, A. crassoramosa, Coenastraea hyatti, Stylina kachensis, Cryptocoenia slovenica, C. wegeneri,
Isastrea hemisphaerica, I. bernensis, Montlivaltia cornutiformis, M. frustriformis, Collignonastraea jumarensis, Ovalastrea
michelini and Vallimeandropsis davidsoni are believed to be recorded for the first time from the Jurassic rocks of central
Arabia. Most corals have massive hemispherical and globular forms, and few corals have dendroid and conical growth
forms. They occur as small, isolated patches, about 0.5m thick and about 10–30m wide, in argillaceous reefal limestones.
The identified corals show Africa, north America, northern, southern and western Europe, and southern or eastern Asia
corals. The low diversity and abundance as well as the small size of colonies are attributed to inimical palaeoecological
factors throughout the reefoids formation such as muddy substratum, water turbidity, high rate of sedimentation.