الفهرس 
Description of Measured SectionsOnly 14 pages are availabe for public view
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Abstract
and bio stratigraphy of the Eocene succession exposed in Helw an area.
few kilometer s to south of Cairo . Six stratigraphic sections were collected and studied
representing Middle and late Eocene ages. These sections from north to south are as follows:
Observatory , East Observatory. Ochsen Rid ge, Sunken Hillock. Wadi Garaw i and Qurn sections. The
rock unit s composing the studied sections are from oldest to youngest as follows: Gebel Hof
(’topmost part ). Observatory. Qurn , Wadi Garawi and Wadi Hof Formations.The Gebel Hof Formation (
topmo st part) together with Observatory and Qurn Formations are considered (Middle Eocene) to be
of Bartonian age, on the other hand , the other two Formations ; namel y Wadi Garawi and Wadi Hof
Formation s of Late Eocene, Priabonian age .
The distribution of the larger foraminifer al species enabled to subdivide the strati graphic
sequen ce into three Biostratigraphi c assemblage zones, these Biostratigraphic units are from base
to top as follows:
I -Dictyocollus aegyptiensis I Idalina cuvillieri Assemblage zone :
In addition to the marker species the followin g speci es are recorded : N.sp .cf. hollingeri. N.b
ullalus and Lockhar tia c[ haimei. This zone attains a thickness of about 14 m. 1t span s the
topm ost
exposed part of Gebel Hof Formation at Ochsen Ridge section . This
zone i s assigned to Bartonian age
2- N ummulites aff.pulche/lus I Nmmu lites beaumonti
Assemblage Zone:
Besides th e mark er speci es the followin g species are record d :
N.b ufla tus .N.beaumomi, N. cf beaumonti, N. sp.c[h olling eri. N.dis corbinus. D ictyoco nus
aegyptiensis and spha erogypsina g lobula. This zone attains a thickne ss ranging from 90 to 145m
1t span s the Observatory and Qurn section . This zone is assigned to Bartonian age.
3- N ummulites striatus Range Zone
This zone attains a thickness of bout 16 m .It characterizes Wadi Garawi and Wadi HofFormations
.This zone is considered to be of Priabonian age according to SCHAUB’S Nu mmuli tic Scale.
The present stud y prooved that the lithostrati graphic classifi cati on of the Eocene sequence in
Helwan FARAG & ISMAIL ( 1960) bel ongs to the Eastern Desert facies representing restricted marin e
en viron
ment especial y during the Bartonian wh ich is distinct and separated from the Mokattam facies.