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

Chapter Three Biostratigraphy
and is mostly well preserved, especially in Smaquli area which showed highest
species diversity than other sections, at the contact of Cretaceous/Tertiary
boundary
Table 3.1 shows the statistics of identified planktonic and benthonic
foraminiferal genera and species belonging to all studied localities were
recorded from the studied sections (Figs. 3.1 - 3.8). The planktonic foraminifera
of globotruncanids, heterohelicids, rugoglobigerinids, globigerinelloidids and
globigerinids are the most prevalent planktonic forams in the studied area and
they show the best indication of typical Tethyan fauna type.
The comprehensive and motif plan in this work was deduced from the
recently planktonic foraminiferal zonation and correlation for the sediments in
tropical/subtropical regions, are widely based on that of Berggren & Miller
(1988), Li and Keller (1998a & b), Liu and Olsson (1992), Berggren et al.,
(1995), Berggren & Norris (1997), Olsson et al., (2000), Arenillas et al., (2001),
Elnady & Shahin (2001), Samir (2002), Abramovich et al., (2002), Keller (2002)
and (2004), Abramovich and Keller (2003), Obaidalla (2005), Smit (2005), and
Sharbazheri (2007), and used exclusively as the biostratigraphic framework in
this study. Fortunately, this zonation proved satisfactory successful results
essentially achieved in different localities of the world.
Li and Keller (1998a) subdivided the Maastrichtian zonal scheme into eight
Cretaceous Foraminiferal (CF) zones labeled (CF8) to (CF1) from the base to
the top; this new biozonation provides accurate and significantly higher
biostratigraphic resolution than previous zonal schemes. They calibrated their
ranges to the paleomagnatic time scale in the DSDP Site 525A, and on
Tunisian sections (Li and Keller 1998b), their age estimation were also
correlated with magnetochron ages by Berggren et al (1995), and consequently
the criteria for age estimation and determination rate of sedimentation can be
proved easily through biostratigraphic correlation and datum event comparison.
The genetic classification and identification used in this study for the
Maastrichtian and Lower Paleocene sediments respectively follow that of Boli
(1966), Postuma (1971), Kassab (1974), (1975d) and (1976), Masters (1977),
Blow (1979), Jenkins and Murray (1981), Caron (1985), Loeblich and Tappan
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