Review of the biostratigraphy of the aruma group (upper cretaceous) in the arabian peninsula and surrounding regions

The Aruma Group (Coniacian-Maastrichtian) in the Arabian Peninsula and surrounding regions consists mainly of limestone with subordinate dolomite and shale interbeds. It is well exposed in central Arabia, but in the eastern regions it occurs only in the subsurface. In the outcrop it has been treated as a formation and divided into three members (Khanasir Limestone, Hajajah Limestone and Line Shale), and nine biostratigraphical assemblage zones (Tissotia, Lopha/Ostrea, Sphaerulites/Biradiolites, Cardium/Protocardium, Gryphaea, Cyclolites, Orbitoides/Lepidorbitoides, Spondylus/Cymatoceras and Omphalocyclus macroporous/Fissoelphidium operculiferum). In the subsurface, it has been given a Group rank and in Kuwait it is divided into three formations (Gudair, Bahrah and Tayarat) and six biostratigraphical zones (Globotruncana renzi, G. elevata/G. coronata, G. stuarti stuartiformis, First zone with no plankton, G. gansseri, and Second zone with no plankton). In the subsurface of Qatar and Abu Dhabi, the group includes four formations for which different terminologies have been used.