Dr. Nagy I. Zoltán szerk.: Fragmenta Mineralogica Et Palaentologica 3. 1972. (Budapest, 1972)
1. Planktonic foraminif eral zonation : Planktonic foraminifera are excellent age indicators, because of their abundance, wide geographical distribution and rapid evolutionary development, further they are ideal fossils for intercontinental geological zoning. The importance of these Microfossils has been considered by many recent workers ex. BOLLI (1957, 1966), EOPKER (196I), LOEBLICH & TAPPAN (1957), SUBBOTINA (1953), BLOW & BANNER (1962) and many others. In Egypt, NAKKADY (1951) was the first to emphasize the value of planktonic foraminifera in the zonation of the CretaceousEocene boundry. On the basis of these planktonic foraminifera, NAKKADY (1951 established three biozones in the Mesozoic - Cainozoic transition in Egypt: - A lower G-lobotruncana zone of Maestrichtian age; a middle Buffer zone 'with abundant Globigerina and devoid from both Globotruncana and Globorotalia of Danian age: An upper sharply keeled Globorotalia zone of Paleocene age. SAID & KENAWY (1956) described the foraminifera of the upper Cretaceous and lower Tertiary from two sections in Sinai. They recognized the zones given by NAKKADY and assigned the Globorotruncana zone to the Maestrichtian, the Globigerina zone (Buffer zone) to the Danian and the Globorotalia zone to the Paleocene . SAID & SABRY (1964) subdivided the upper Cretaceous lower Tertiary succession of Gebel Aweina, Nile Valley according to the planktonic foraminifera into a number of zones that are of world wide distribution. These are as follows: The Globotruncana - Heterchelix zone denotes a Maestrichtian age. Globigerina daub.iergensis - G. pseudobulloides zone of Danian age. G. uncinata, G. pusilla pusilla and G. pseudomenardii , and G. velascoensis zones of Landenian age; and the G. rex zone of lower Eocene age.
