biostratigraphy and paleoecology of cretaceous/tertiary boundary in ...

Chapter Four
Depositional Environmenment and Paleoecology
and others, 2002b in Keller, 2004), (Abramovich. and Keller, 2002). (Samir,
2002),
4.5- The Nature of Maastrichtian/Paleogene boundary
At Smaquli, Qulka and Sirwan valley extremely rich in microfauna especially
planktonic foraminifera. High resolution biostratigraphic analysis of these
sections indicates a major biotic change in planktonic foraminiferal
assemblages. Neither burrows (trace fossils) nor sedimentary structures,
condensed sections, hard ground, mineralization bed of glauconitic, Iron
oxide, silicate, silica spheres, microtectites or any Phosphatic minerals
have been found at the K/T boundary. In addition, the great similarities in
the lithologic components below and above the contact line between
Tanjero and Kolosh Formations, in which impossible to distinguish or to
differentiate between them lithologically in the field. The planktonic
foraminiferal biozones recorded in the studied area reveals continuous
sedimentation without evidence of any hiatus (Figs 3.1-3.8) in addition to the
appearance of the new lower most Danian Planktonic forams which indicate
the gradual contact at Smaquli area. These data are similar to those
identified from El Kef in Tunisia (Keller et al., 1995); Agost, Caravaca,
Zumaya, in Spain (Canudo et al., 1991: Pardo et al., 1996: Molina et al.,
1996, 1998); Ain Settara in Tunisia (Arenillas et al.. 2000); Caravaca SE Spain
( Smit, 2005); Egypt (Shahin, 1992), (Samir, 2002), ((Keller, 2002),(Obaidalla,
2005) and Israel (Keller ,2004).
The extinction pattern of the Late Maastrichtian fauna has been a matter of
controversy. In this connection, Smit (2005) studied the planktonic foraminiferal
pattern of extinction across the (K/P) boundary at Caravaca SE Spain, and
believed that the bolide impact event caused the extinction of all Cretaceous
fauna, except for one species (G. cretacea) which considered the
occurrence of Cretaceous individuals above the K/P boundary as due to
reworking. Keller (1988) in Obaidalla, 2005 proposed that the 14 Cretaceous
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