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 dol omite and shale interbeds. It is well exposed in central Arabia, but i n the eastern regions it occurs only in the subsurface. In the outcrop it has been treated as a formation and divided into three members (Kh anasir Limestone, Hajajah Limestone and Line Shale), and nine biostrat igraphical assemblage zones (Tissotia, Lopha/Ostrea, Sphaerulites/Bira diolites, Cardium/Protocardium, Gryphaea, Cyclolites, Orbitoides/Lepid orbitoides, Spondylus/Cymatoceras and Omphalocyclus macroporous/Fissoe lphidium 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 pl ankton, G. gansseri, and Second zone with no plankton). In the subsurf ace of Qatar and Abu Dhabi, the group includes four formations for whi ch different terminologies have been used.