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

Chapter Four
Depositional Environmenment and Paleoecology
4.4.1- Maastrichtian
The Maastrichtian succession represented by upper most part of
Shiranish Formation (samples 1-5), Reddish to pale brown succession
(Shiranish-Tanjero transition unit), (Samples, 6-40) and Tanjero Formation
(samples, 41-113) in Smaquli area, while in the other localities, the studied
part of Late Maastrichtian succession, represented by the upper part of the
Tanjero Formation (in Dokan, Qala Cholan, Barzinja and Sirwan valley) is
characterized by the following parameters:
1- The most diverse assemblage of planktonic foraminiferal species
richness ranged from 45 – 55, P/B ratios from 65-80% and Aggl/Calc
percent from 15-25% (From CF8 – CF2) Zones, with decreasing the species
richness in (CF1) Zone which is being 34-27 and slightly increasing in
Agglutinated/Calcareous percent to 35%, In Smaquli section (Fig. 4, 3).
2- Planktonic foraminifera species richness from 35 – 45, P/B ratios from
50-70% and Aggl/Calc percent from 15-20% with decrease in species
richness in (CF1) Zone from 24-20 and slight increase of
Agglutinated/Calcareous percent to 30%, In Qulka section (Fig. 4 ,4).
3- Planktic foraminiferal species richness is ranged between 35 -45, P/B
ratios between 55-70% and Aggl./Calc. percent from 18-30%, with decreasing
the species richness from (CF2 &CF1) Zones from 30-22 and slightly
increasing in Aggl./Calcar. Percent 50% within the upper most part of (CF1),
In Sirwan section (Fig. 4, 5).
4- Planktonic foraminiferal species richness is 25, P/B ratios are 45% and
Aggl./Calc. Percent ranged between 35-40% in the lower part of Qishlagh
section (sample 1-11) with decreasing in Agglu./Calc. percent 10–20 in the
middle part (sample 12-33) and increasing to 35-40% in (samples 35-46) (Fig.
4 ,6).
5- Planktonic foraminifera species richness is 30, P/B ratios are 45% and
Aggl/Calc percent is 23% in the lower part of Kato section (samples, 1-19)
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