PALYNOFACIES ANALYSES AND PALAEOENVIRONMENTS OF SOME
LOWER CRETACEOUS ROCKS OF THE SIQEIFA 1X BOREHOLE,
NORTH WESTERN DESERT, EGYPT
Magdy S. Mahmoud*,, Mohamed A. Masoud**, Mohamed A. Tamam**, and
Miran M. Khalaf**
* Assiut University, Faculty of Science, Geology Department, Assiut, Egypt
** Sohag University, Faculty of Science, Geology Department, Sohag, Egypt Corresponding author e-mail: [email protected]
ABSTRACT
A detailed palynofacies analysis was carried out on 56 ditch-cutting samples
obtained from the lower Cretaceous of Siqeifa 1x borehole, north Western
Desert, Egypt. The main aim of this study is to identify depositional
palaeoenvironments in details, reconstruct vegetation cover and to infer
palaeoclimate conditions. Three palynofacies types were recognised;
palynofacies type (PF-1) corresponds to the lower-middle Alam El Buieb
Formation (Berriasian-Barremian). This is deposited in a deltaic (prodelta)
subenvironment during a Berriasian-early Barremian regression episode, and
the lower upper Alam El Buieb deposited in an inner shallow marine
environment during a partial regain of a late Barremian-Aptian transgression,
under prevailing dysoxic-anoxic to suboxic-anoxic conditions. The second
palynofacies (PF-2) represents the uppermost Alam El Buieb, Alamein, and
Dahab formations (late Barremian-Aptian), where the uppermost Alam El-
Buieb Formation was deposited in a distal bar of a prograding delta,
accumulated during a minor local regression. However, the carbonate of the
Alamein Formation and the shale of the Dahab Formation was deposited in a
saline lagoon environment developed during a partial regain of the local early
Aptian marine transgression. Suboxic-anoxic to dysoxic-anoxic conditions are
interpreted to prevail during deposition of the PF-2. Third palynofacies (PF-3)
represents the Kharita Formation (Albian), where the lower Kharita was
deposited in a lagoon setting, while the upper Kharita was deposited in a
deltaic environment due to a major marine regression, under dysoxic-suboxic
conditions. Local pteridophyte vegetation on low lands near the borehole and
conifers on relatively dry hinterlands is interpreted to thrive under a regional
warm and relatively dry palaeoclimate. Possible seasonal dry periods may be
developed during deposition of the uppermost Alam El Buieb, Dahab and
Alamein formations.
THE SEVENTH INTERNATIONAL CONFERENCE
ON THE GEOLOGY OF AFRICA
P-P VI-33 – VI-58 (NOV. 2013) ASSIUT-EGYPT
VI-34 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
1. INTRODUCTION
The lower Cretaceous in the north Western Desert exhibits a major regressive
phase indicated by clastics (Said, 1990). Neocomian-Barremian sedimentation
represents a regressive phase and marginal marine sandstone and shale of the Alam
El Buieb Formation were deposited. The Aptian witnessed a transgressive phase,
which brought a shallow sea over the north Western Desert, while the carbonate
unit of the Alamein Formation was deposited. The Albian time is represented by
another regressive phase, when the north Western Desert was receiving the fluvial
(mainly coarse sands) sediments of the Kharita Formation coming from the south.
However, in the extreme north, specifically at the Matruh Basin, sedimentation of
fine silt and shale was dominant (Said, 1990).
Combaz (1964) introduced the term palynofacies as “the total complement of
acid-resistant particulate organic matter recovered from sediments by
palynological processing techniques”, and based on this term palynofacies analysis
was used to interpret palaeoenvironments. However, Tyson (1995) provided the
most recent and widely used definition of the palynofacies term as “the total
particulate organic matter assemblage contained in a body of sediment thought to
reflect a specific set of environmental conditions, or to be associated with a
characteristic range of hydrocarbon-generating potential”. The later term can be
used in palaeoenvironments interpretation as well as in source rock evaluation, and
will be used here because it links palynofacies types to sedimentary sequences.
Palynofacies analysis is interested with changes in the relative abundance of various
types of sedimentary organic matter as palynomorphs, phytoclasts, and amorphous
organic material (AOM). Because palynofacies analysis is closely linked to
sedimentology, it can thus used in identifying palaeoenvironmental and
hydrographic parameters such as distance from shoreline, hydrodynamic energy in
the water column, salinity, and oxygen regime (e.g. Tyson, 1995; Batten, 1996).
Several palynological investigations have dealt with the palaeoenvironmental
interpretations of the Egyptian Cretaceous rocks (e.g. Abdel-Kireem et al., 1996,
Ibrahim, 2002; Zobaa et al., 2013). However, the use of detailed palynofacies
analyses in interpreting palaeoenvironmental settings still lacking. Mahmoud and
Deaf (2007) studied the palynostratigraphy of the lower Cretaceous succession
penetrated by the Siqeifa 1x well borehole northern Western Desert, Egypt. The
present work aims to study the palynological facies of the Siqeifa 1x with more
detailed analyses upon the percentage distribution of the palynological organic
matter (POM) assemblages to infer the palaecological settings in terms of
depositional palaeoenvironments, palaeoclimate, and palaeovegetation covers.
2. MATERIAL AND METHODS
The present study is based on fifty-six ditch cutting samples were collected from
the lower Cretaceous of the Siqeifa 1-X borehole, Matruh Basin, northern Western
Desert (Fig. 1). The samples were processed by standard (HCl-HF) palynological
preparation technique, without oxidation or ultrasonic treatments. The palynological
residue was sieved through 10 μm nylon sieves. Three to five permanent slides were
prepared using glycerin jelly as a mounting medium. It should be noted that neither
ultrasonic nor oxidation (nitric acid) treatments were carried out, where these
analyses would results in oxidation and inevitable destroyment of the plant debris
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-35
and the palynomorphs. All slides and residues are stored and catalogued in the
Geological Museum, Geology Department, Faculty of Science, Sohag University,
Egypt.
Figure 1. Geographic map of Egypt showing the location of the Siqeifa 1-X well
(After Abdel Kireem et al., 1993)
Palynological slides were examined using the transmitted light microscopy
Olympus BX41 Microscope at X 200 and X 500 magnifications in order to:
establish semi quantitative analysis of the POM; determine the palynofacies types
and the palaeoenvironmental interpretations. The photomicrographs are published
in Mahmoud & Deaf (2007). For full reference to taxa refer to Mahmoud & Deaf
(op. cit.). Each slide was counted for its POM content, in which the first 200
particles were categorized as abundant >35 %, frequent 16-35 %, common 5-15 %
and rare <5 %. The palynofacies analysis is based on the percentage frequency of
different POM constituents categorised by Tyson (1995). The percentage of each
palynomaceral component is derived from the total POM frequencies. However, the
species richness and percentage of dinoflagellate cysts morphotypes were obtained
from the total dinoflagellate cysts frequencies.
3. LITHOSTRATIGRAPHY
The operating drilling company WEPCO (1970) did not recognised most of the
formations in the studied borehole, and only provided detailed information on
lithology, unit thicknesses, and tops of these lithologic units. Thus, the lithology
description, which has been provided by the company and the palynological age
dating provided by Mahmoud & Deaf (2007) will be used to identify formations in
the borehole (Fig.2). Description of the Cretaceous formations in the Stratigraphic
Lexicon of Egypt (Hermina et al., 1989) and that provided by Hantar (1990) were
consulted.
Siqeifa 1-
X
VI-36 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
Figure 2. Lithologic column of the Siqeifa 1x borehole (After Mahmoud & Deaf, 2007)
3.1 Alam El Bueib Formation
This formation is composed of sandstone with frequent shale interbeds in its
lower part and occasional limestone in its upper part, but in the Siqeifa 1-X well, the
formation is mainly composed of thick shale unit intercalated with very minor
streaks of sands, and shows more sandy facies at its bottom and top. This shale unit
was commonly referred to as the Matruh shales or the Mersa Matruh Formation of
Norton (1967). Its type section is the interval from 3927 to 4297 m of the Alam El
Bueib-1 well (Hantar, 1990). This formation ranges in age from Barremian to
Aptian (Hantar, 1990). WEPCO (1970) referred to this unit in the investigated well
as: no information, top of Umbaraks Sands, and top of Matruh Shale. Based on the
palynology work of Mahmoud and Deaf (2007) and lithologic description provided
above, the thick 869 m (2850 ft) clastic sequence confined between depths 3463 and
2594 m (11950-9100 ft) can be identified as the Alam El Bueib Formation and
given a Berriasian-Barremian age. This formation is belived to be deposited under
shallow marine conditions with more continental influence towards the south
(Hantar, 1990).
3.2 Alamein Formation
This unit consists mainly of hard dense brown dolomite with a few thin shale
interbeds at its base and top (Hantar, 1990), but in the Siqeifa 1-X well, it is
composed of chalky limestone intercalated with minor shale streaks. It rests
conformably over the Alam El Bueib Formation and underlies the Kharita
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-37
Formation (Hantar, 1990). In type section it measures 84 m (276 ft) thick at depths
2489 to 2573 m of the Alamein-1 well (Hantar, 1990). The age of the formation was
reported at the type section to be Aptian to Albian age (Hantar, 1990), but in the
Siqeifa 1-X well, Mahmoud & Deaf (2007) assigned an early Aptian age for the
carbonate unit confined between depths of 2487-2427 m (8750-8550 ft). The
described unit seems to have been deposited in a shallow marine, low to moderate
energy environment (Kerdany & Cherif, 1990).
3.3 Dahab Shale
It is composed of a shale unit interbeded with thin streaks of siltstone and
sandstone at its type section. In the Siqeifa 1-X well, this unit has a similar
lithological composition, but it contains minor black carbonaceous material and
pyrite in shale, and dolomite and anhydrite streaks in the sandstone beds. This
formation is conformably underlain by the Alam El Bueib Formation and overlain
by the Kharita Formation. The type section is the interval between 3180 to 3354 m
of the Dahab-1 well. This unit is attributed an Aptian-early Albian age (Hantar,
1990). In the investigated well, this formation was not identified by WEPCO (1970)
and the palynological dating of Mahmoud & Deaf (2007) suggests sediments at
depths 2366-2076 m (8350-7400 ft) as comprising the Dahab Formation of a mid to
late Aptian age. The Dahab Formation seems to be deposited in a shallow marine
environment (Barakat & Darwish, 1987; Hantar, 1990).
3.4 Kharita Formation
This formation consists of fine to coarse-grained sandstones with interbeds of
greyish green shale and some carbonates at its type section (389 m/1276 ft) at the
Kharita-1 well. In the studied well, the formation is composed essentially of
medium to coarse-grained sandstone containing minor pyrite and frequent
carbonaceous matter, and intercalated with thin shale and siltstone streaks. It rests
conformably over the Dahab Formation and underlies the Bahariya Formation
(Hantar, 1990). The Kharita Formation is assigned to be of Albian to Cenomanian
age (Hantar, 1990). In the Siqeifa 1-X well, WEPCO (1970) referred to the section
(457 m/1500 ft) at depths from 2061 to 1604 m (7350-5850 ft) as no information.
Based on the palynostratigraphic study of Mahmoud & Deaf (2007), this sequence
can be recognized as the Kharita Formation of the Albian age. The Kharita
Formation was most probably deposited in an extensive shallow marine shelf in a
littoral setting (Hantar, 1990; Kerdany & Cherif, 1990).
4. RESULTS OF PALYNOFACIES ANALYSIS AND INTERPRETED
PALAEOENVIRONMENTS
The palaeoenvironmental interpretations presented here are mainly depending on
the semi-quantitative palynofacies characteristics of selected constituents of the
palynological matter, which are known to have a palaeoenvironmental significance.
Certain sporomorphs are indicators of specific ecological parameters and thus are
useful in identifying palaeoclimatic conditions and in reconstructing the vegetation
cover grew on the source area.
The changes in the palynofacies composition in the Siqeifa 1x well (Figs. 3 & 4),
and the AOM-palynomorphs-phytoclasts (APP) ternary plot (Fig. 5) reveal three
palynofacies types in the lower Cretaceous of the study well these are described as
follows.
VI-38 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
Figure3. Percentage abundances of some selected palynomorphs and particulate
organic matter of the Siqeifa 1x borehole, northern Western Desert, Egypt
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-39
Figure 4. The percentage of dinoflagellate cyst abundances, species richness, and
different cyst morphotypes, the Siqeifa 1x borehole, northern Western Desert, Egypt
VI-40 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
4.1 Palynofacies PF-1: Prodelta to inner shallow marine
This palynofacies (samples 1-21) is considered as the oldest one; it covers the
depth from 11950 to 9550 ft (3463-2716 m) and corresponds to the lower-middle
Alam El-Buieb Formation. It is characterized by abundant AOM (avg. 46%),
abundant phytoclast (avg. 43%) and common sporomorphs (avg. 9.8%), whereas
the marine palynomorphs are represented by rare (avg. 3 %) dinoflagellate cysts and
rare (avg. <5 %) MTLs (Fig. 3; Pl. 3, Fig. 1).
The rare dinoflagellate cysts abundances and moderate species richness (avg. 4)
of this palynofacies indicate stressed marginal marine environment of below normal
salinity (e.g. Batten, 1983; Lister & Batten, 1988). The dominance of the cavate
(avg. 35 %) and proximate (avg. 32 %) cysts such as Pseudoceratium,
Cribroperidinium, and Circulodinium characteristic of brackish water conditions
over the open marine (middle shelf) chorate (avg. 8%) cysts (Fig. 4), suggests
deposition of samples 1-15 of PF-1 in a brackish marginal marine environment (e.g.
Harding, 1986; Lister & Batten, 1988). The sporadic occurrence of the low salinity
genus Muderongia in PF-1 also supports this brackish conditions (e.g. Lister &
Batten, 1988). The abundance of the dinoflagellat cysts shows a slight rise at the
upper part (samples 16-21) of the described palynofacies, which indicates a
comparatively more distal depositional setting than that recorded for the lower part
of PF-1 (Tyson, 1995). Percentages of dinoflagellate cysts have been found to
exhibit offshore increases with increased water depth (e.g. Tyson, 1984, 1993). This
suggests that a minor marine transgression related to a loacl sea level rise took place
during deposition of this part of PF-1 (e.g. Lister & Batten, 1988). This is most
propabaly related to the global late Barremian-Aptian transgression (Vail et al.,
1977; Said, 1990). The rare occurrence (1.7 %) of MTLs in the upper part (samples
12-19) of PF-1 supports the suggested minor transgression, as MTLs are indicative
of marine conditions (e.g. Lister & Batten, 1988; Stancliffe, 1989) and typically
show very low frequencies in distal deltaic facies (Traverse, 1988).
Dominance of the continental (avg. 9.8% of total POM) over the marine (avg.
4% of total POM) palynomorphs generally indicates proximity of the depositional
site to active fluvio-deltaic systems (e.g. Tyson, 1993; Batten, 1996). The override
of pteridophyte spores (avg. 6%) over sphaeroidal (Araucariacites, Balmeiopsis,
Exesipollenites) gymnosperm pollen grains (avg. 3%) in the sporomorph
assemblage suggests deposition of PF-1 in shallow marginal marine settings, most
probably in a deltaic setting. This is based on the ecological preference and
reproduction rates of the spore-parent plants, as they thrive in swampy deltaic areas
and are known to be less productive than the gymnosperm pollen-producing plants.
In addition to the fact that pteridophyte spores have relatively limited transport
efficiency in contrast to the more buoyant and easily transported sphaeroidal pollen
grains (e.g. Tyson, 1995; Traverse, 2007).
Here, the percentage distribution of terrestrial plant debris plays a main role in
the suggestion of the possible palaeoenvironmental settings of PF-1. The high
abundance (avg. 43%) of the palynodebris (Fig. 3) generally reflects strong
terrestrial influx and deposition in marginal marine environments close to land
vegetation (e.g. Tyson, 1993; Al-Ameri et al., 2001). The frequent brown wood
(avg. 34 %) indicates deposition in a relatively low energy, distal marginal marine
setting of reducing (dysoxic-anoxic to suboxic-anoxic) conditions acording to the
Tyson’s (1995) ternary plot (Fig. 5, Tab. 1). In marine sediments, abundant brown
wood fragments were found to concentrate in the high energy, proximal sand and
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-41
silt facies and decrease in a basinward direction in the low energy finer sediments
(Habib, 1983; Firth, 1993; Tyson, 1995).
Figure 5. The Siqeifa 1x palynofacies plot in the ternary kerogen diagram of Tyson,
1995
By connecting the brown wood percentages of PF-1 to its lithology: brownish
grey to partly greenish grey shale, silty shale, and shale with minor sandstone
streaks, it is most likely that PF-1 was deposited in the subaqueous, relatively low
energy, prodelta subenvironment to inner shallow marine settings. Prodelta
sediments are shallow marginal marine clastics consist of silty clay that is
occassionally intercalated with thin streaks of coarse silt and find sands, and usually
contains marine fauna (here recognized MTLs) and frequent plant fragments (e.g.
Einsele, 1992; Nichols, 2009). High black wood percentages correlate with
relatively high energy silt and sands of fluvial and delta-top environments (Nagy et
al., 1984; Smyth et al., 1992; Williams, 1992). Thus, the low (avg. 8 %) black
woods recorded from the silty shale of PF-1 would imply a limited bacterially-
driven, in situe post-depsitional oxidation of brown wood during periodical
fluctuations in water table (Tyson, 1995) or due to seasonal low runoff and limited
supply of fresh wood fragments (Hellem et al., 1986; Marzi and Rullkotter, 1986).
Fractionation of fluvial and delta-top large black woods that were transported to
delta-front and re-deposited by wave and current actions (Tyson, 1995) and/or
directly blown by wind (e.g. Summerhayes, 1987; Ten Haven et al., 1990) into the
more distal, redcuing prodelta slope are also possible explanations for the present
low black wood frequency. Very low abundance (avg.1 %) of membranous tissue
generally indicates deposition in low energy, shallow marginal marine settings.
Membranoues tissues were found to be common in non-marine (e.g. bogs)
sediments and decrease in the brackish-marine, proximal deltaic (lower delta plain)
VI-42 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
facies, and become rare in marine sediments (e.g. Lamberson, et al., 1991; Tyson,
1995).
The shale lithology with its very high (avg. 46 %) AOM content and the marked
dilution of the phytoclast content by AOM in PF-1 suggest high rate of
sedimentation and rapid burial in somewhat farther settings slightly removed from
active, non-marine sources, where the dysoxic-anoxic to suboxic-anoxic conditions
prevailed (Tyson, 1995).
From the above discussion, it is suggested that the silty shale of the lower-
middle Alam El Buieb Formation (samples 1-15) was deposited mainly in a
prodelta setting but with its lower upper part (samples 16-21) of the formation
deposited in an inner shallow marine setting, under dysoxic-anoxic to suboxic-
anoxic conditions.
Table 1. Key to marine palynofacies fields indicated in ternary diagram
(Modified from Tyson, 1995).
Spores:
Bisaccate
II Marginal
dysoxic-
anoxic
basin
AOM diluted by high phytoclast input, but AOM preservation
moderates to good. Amount of marine TOC dependent on basin
redox state. Generally low AOM preservation.
High Very low III (gas prone)
III Heterolithic
oxic shelf
("proximal
shelf")
Absolute phytoclast abundance dependent on actual proximity to
fluvio-deltaic sources. Oxidation and reworking common.
High Common to
abundant dinocysts
dominant
III or IV (gas
prone)
IV Shelf to
basin
transition
Passage from shelf to basin in time (i.e. increased
subsidence/water depth) or space (e.g. basin slope). Absolute
phytoclast abundance depends on proximity to source and
degree of redeposition. Amount of marine TOC depends on basin
redox state. Iva dysoxic-suboxic, IVb suboxic-anoxic.
Moderate to
high
Very low-low III or II (mainly gas
prone)
V Mud-
dominated
oxic (distal)
shelf
Low to moderate AOM (usually degraded). Palynomorphs
abundant. Light coloured biotrubated, calcareous mudstone are
typical.
Usually low Common to
abundant dinocysts
dominant
III > IV (gas prone)
VI Proximal
suboxic-
anoxic
shelf.
High AOM preservation due to reducing basin conditions.
Absolute phytoclast content may be moderate to high due to
turbiditic input and/or general proximity to source.
Variable low
to moderate
Low to common
dinocysts dominant
II (oil prone)
VII Distal
dysoxic-
anoxic
"shelf".
Moderate to good AOM preservation, low to moderate
palynomorphs. Dark-coloured slightly biotrubated mudstones are
typical.
Low Moderate to
common dinocysts
dominant
II (oil prone)
VIII Distal
dysoxic-
anoxic
shelf.
AOM-dominante assemblage, excellent AOM preservation. Low
to moderate palynomorphs (partly due to masking). Typical of
organic-rich shales deposited under stratified shelf sea conditions
Low Low to moderate
dinocysts dominant,
% prasinophytes
increasing
II >> I (oil prone)
IX Distal
suboxic-
anoxic
basin.
AOM-dominant assemblages. Low abundances of palynomorphs
partly due to masking. Frequently alginate-rich. Deep basin or
stratified shelf sea deposits, especially sediments starved basins.
Low Generally low,
prasinophyte often
dominant
II ≥ I (highly oil
prone)
III (gas prone)
Palynofacies
field and
environment
Comments Microplankton Kerogen type
I Highly
proximal
dysoxic-
anoxic
basin
High phytoclast supply dilutes all other components Usually high Very low
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-43
4.2 Palynofacies PF-2: Deltaic to lagoon
Samples (22-42) recovered from depths 9450 to 7350 ft (2701-2061 m)
represents Palynofacies 2, which corresponds to the upper Alam El-Buieb
Formation, Alamein and Dahab formations. PF-2 is characterized by abundant
phytoclast (46%), frequent AOM (30%) and frequent sporomorph (19%), whereas
the marine palynomorphs are represented by rare (3%) dinoflagellate cysts and rare
(<5 %) MTLs (Fig. 3; Pl. 3, Fig. 2).
This palynofacies shows a slight decrease in marine (avg. 3%) palynomorphs in
comparison to PF-1, which indicates a comparatively more proximal depositional
setting than that recorded for PF-1 (Tyson, 1995). This decrease in species
abundance and the accumulation of alternating very fine sands and shale of samples
22-26 of PF-2 over the finer prodelta-inner shallow marine shale of PF-1 (Fig. 3),
indicates a minor regression and development of a new sedimentation cycle of a
prograding delta with its distal bar showing the coarsening upward sequence
(Boggs, 2006). On the other hand, the gradual upward increase in marine
palynomorphs and high dominance (avg. 67%) of the open marine dinoflagellate
cysts (e.g. Oligosphaeridium and Florentinia) accompanied with decreases in ratios
of the cavate (avg. 24%) and proximate (avg. 10%) cysts recorded from all samlpes
of PF-2, generally indicate development of inner open marine conditions. This may
point out to a gradual regain of the local late Barremian-Aptian transgression noted
in the underlying PF-1. The frequent presence of black carbonaceous material and
pyrite in shale and sandstone beds, and dolomite and anhydrite streaks in most
samples (27-42) of PF-2, and thick (376ft/114m) dolomite sequence indicates a
reduced distal setting that is slightly removed from high freshwater supply and is
partially isolated from normal marine water, and suggests a saline lagoon
environment (Boggs, 2006). An explanation that would justify the presence of open
marine dinocysts in the suggested lagoon is that tidal currents of the tidal channel
inlet of lagoons usually remove parts of the open marine sediments and fossils,
redistribute and concentrate them in the low energy area of the lagoons (Tyson,
1984, 1993; Boggs, 2006). Another factor that may in part contribute to this inverse
picture is the selective preservation during deposition in relatively oxic to suboxic
nearshore settings, which might overprint the original primary productivity of
cavate peridinioids. The peridinioid cysts are known to be sensitive to aerobic decay
(Zonneveld et al., 2009). The rare ocurrence of MTLs also supports the stressed
(saline) marine conditions.
The common frequencies of pteridophytes (avg. 11%) and its gradual upward
increase (samples 22-35) indicate a distal depositional setting that is relatively close
to an active deltaic system and shows gradual shifts in deposition in a basin ward
direction. The thin-walled spores such as pteridophytes are known to be controlled
hydrodinamically by their graine size and tend to increase in percentages in an
offshore direction, in the distal low energy settings of delta systems (e.g. Tyson,
1989; Dybkjaer, 1991). A further development of distal low energy settings is
suggested for the upper part (samples 36-42) of PF-2, based on the moderate
increase in the sphaeroidal pollen frequencies (avg. 6%), where these pollen grains
are known to have increase in percentage frequency in a shelfal direction (Hughes
& Moody-Stuart, 1967; Habib, 1979). The minor ocurrence of the xerophytic pollen
grain Ephedripites at the middle and upper parts of PF-2, and its complete absence
in the underlying and overlying palynofacies types, indicates ocurrence of a semi-
VI-44 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
arid condition during deposition of these parts of PF-2 (Doyle, 1999), which
supports the suggested saline lagoon setting.
The brown wood (avg. 45%) increases in samples (22-35) at the expense of the
AOM (30%) indicate strong terrestrial influx and deposition in proximal settings
that is close to the parent land plants (Tyson, 1993). Diminishing in the brown wood
(avg. 27%) frequency in the uppermost part (samples 36-42) of PF-2 reflects more
offshore settings. The general upward decrease in black wood percentages (7%)
also supports the development of reduced, low energy distal settings, where this
wood is known to show a general offshore decline in frequency (Tyson, 1995). The
persistant low concentrations of membrance tisuue (avg. 1%) reflects the general
marine conditions and in part the dilution effect of other terrestrial and marine
components (Tyson, 1995).
AOM of PF-2 shows a significant lower frequency (avg. 30%) than that recorded
from the underlying PF-1 (avg. 46%) and supports the more proximal setting of PF-
2 (Tyson, 1993). Samples 22 to 35 reflect this proximal setting, where it still diluted
by high phytoclast input (Fig. 3), but the general upward increase in the AOM
reflects development of distal settings of dysoxic-anoxic conditions (e.g. Dow &
Pearson, 1975; Bujak et al., 1977). The plot of PF-2 in the ternary kerogen of Tyson
(1995) suggests suboxic-anoxic to dysoxic-anoxic conditions to have prevailed
during despoition of the palynofacies, and where he suggested the facies as
characteristic of shelf to basin transition.
Combining all information mentioned above, the very fine sand and shale
sediments comprising the uppermost Alam El-Buieb Formation (samples 22-26)
seem to represent a part of the distal bar of a prograding delta accumulated during a
minor local regression. The carbonates of the Alamein Formation and the overlying
shale of the Dahab Formation are suggested to be deposited in a saline lagoon
environment developed during a partial regain of the local early Aptian marine
transgression. Deposition of the PF-2 sediments is interpreted to take place under
suboxic-anoxic to dysoxic-anoxic conditions.
4.3 Palynofacies PF-3: Lagoon to deltaic
This palynofacies (samples 43-56) occupies the depth from 7250 to 5850 ft
(2030-1604 m), which corresponds to the Kharita Formation. It is characterized by
abundant phytoclast (57%), frequent AOM (20%) and frequent sporomorphs (22%),
whereas the marine palynomorphs are represented by rare dinoflagellate cysts
(<5%) and MTLs (Fig. 3; Pl. 3, fig. 3).
The sharp upward decline in the abundance (avg. 1%) and species richness (avg.
3%) of the dinoflagelate cysts in comparison to that of PF-1 and PF-2 indicates a
development of strong marine regression and deposition in a very shallow maine
grades upward into a coastal condition (e.g. Tyson, 1993). This may be related to a
local (Said, 1990) and global drop in sea level by the end of the Aptian, and
development of a major marine regression by the early Albian time (Murris, 1980).
At the base (samples 43-52) of PF-3 shale beds are alternated with fine to coarse
sandstones and grades upward (samples 53-56) into coarser sand beds intercalated
with minor shales. The whole sedimentary sequence shows a coarsining upward
sequence and contains minor black carbonaceous material, pyrite, dolomite and
anhydrite streaks in most samples of PF-3, which indicates a lagoon (samples 42-
52) grades upward into a deltaic (samples 53-56) setting. Here again the chorate
cysts percentages (avg. 60%) are greater than those of the cavate cysts (avg. 20%),
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-45
and this cannot be used to infer more open marine environment of the formation. As
is mentioned above, this is may be explained as due to action of tidal currents on
open marine sediments and also to the selective preservation. This in turn suggests a
development of a tide-dominated delta setting for the upper part (53-56) of PF-3.
The upwrad increase in spore concentrations from common (avg. 13 %) at the
base to abundant (40%) at the top of the palynofacies supports the regressive marine
deposition and transition form lagoon to delatic setting. The relatively higher
concentration of spores (avg. 13 %) compared to saccate pollen grains (avg. 9%)
also indicates a high energy proximal setting (Tyson, 1993).
The brown wood (avg. 37 %) is the most common phytoclast constituent, while
membranous tisuue (avg. 1 %) is very rare. The high supply of brown wood
sufficient to dilute all other components is characteristic of proximal settings, where
deposition takes place close to the parent flora (Tyson, 1993). The higher
abundance of black wood (avg. 20 %) of PF-3 in comparison to that recorded from
PF-1 and PF-2 and its upward increase suggests deposition of PF-3 in higher energy
settings than that inferred for PF-1 and PF-2. This setting indicates partial oxidation
before or during final deposition (Tyson,1995). This material as in PF-1 probably
represents the in situ post-depositional bio-oxidation of normal wood particles
during seasonal fluctutions in water table conditions, where such oxidation takes
place in littoral sediments with tidally fluctuating water tables (Pocock, 1982). In
general, the high proportions of the brown and black wood are known to
concentrate in proximal onshore settings that indicate proximity to shoreline and
deposition under dysoxic-suboxic conditions and the highest concentration of
terrestrially derived organic matter over the marine palynomorph, both
characteristics of marginal marine conditions.
The decreases in abundance of AOM (avg. 20 %) compared to the two
underlynig palynofacies types indicate shallow shelf sediments (e.g. Dow &
Pearson, 1975; Bujak et al., 1977). Plot of PF-3 constituents in the kerogen diagram
suggests deposition of the palynofcaies in a proximal basin of dysoxic-suboxic
conditions.
Combining all of these characteristics given previously, the sediments of PF-3
making up the Kharita Formation, were probably deposited in a lagoon (samples 43-
52) changed upward into a deltaic (samples 53-56) environment, during local and
global early Albian regression, under prevailing dysoxic-suboxic conditions.
5. PALAEOVEGETATION AND PALAEOCLIMATE
The study of the terrestrial palynomorphs recovered from the investiged
successions of the Siqeifa 1x borehole suggests a subtropical to tropical vegetation
cover near the study area. The abundance of the mainly fern spores represented by
pteridophytes (e.g. Deltoidospora) and Schizaeacean (Cicatricosisporites) in all
studied samples probably reflects local pteridophyte vegetation on wet lowlands
(Playford 1971; Schrank & Mahmoud 1998). The differences in percentage
frequency of terrestrial palynomorphs are mainly effected by the changes in the
sedimentation trends (i.e. transgression-regression) which is considered as the more
important parameter than any other ecological parameters on land as these fern
spores show a taxonomic stability through the analysis of the all studied sections
(Deaf, 2009). The common araucariacean pollen frequency reflects a conifer forests
VI-46 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
on relatively dry hinterlands (Schrank & Mahmoud 1998; Schrank 2001; Mahmoud
& Moawad 2002).
The frequent occurrences of the Afropollis and Elaterate pollen grains indicate
more local coastal humid conditions near the site of the borehole (Schrank 2001).
The unusual high percentage (38 % of total palynomorphs) of the elaterate pollen
grains in a single horizon (Sample 44, depth 7100 ft/1985 m) at the lower Kharita
Formation of the Seqiefa 1x borehole indicate more local temporary short term
coastal humidity (Schrank, 2001; Mahmoud & Deaf, 2007). The consistent
occurrence of the drought resistant Cheirolepidiacean conifer pollen grains
Classopollis, which vegetate in hot subtropical latitudes (e.g. Doyle, 1999) indicates
regional hot and relatively dry conditions (e.g. Watson 1988; Doyle 1999). Doyle et
al. (1982), Schrank (1990), and Brenner (1996) all suggested relatively wetter
palaeoclimates for the African palaeotropics (e.g. Egypt and Sudan) based on the
lower frequencies of Classopollis than seen in the palaeosubtropics. The xerophytic
Ephedripites pollens (e.g. Doyle, 1999) reflect warm and relatively dry
palaeoclimate, which could imply the occurrence of seasonal dry periods during
deposition of the upper Alam El Buieb, Dahab and Alamein formations.
The Albian-Cenomanian Elaterate Phytogeographic Province of Herngreen et al.
(1996) had a paleoequatorial distribution corresponding to an arid to semi-arid
warm climate (El Beialy, 1994; Aboul Ela et al., 1996; Herngreen et al., 1996;
Ibrahim, 2002; Mahmoud & Moawad, 2002). However, the occurrence of fern
spores, mainly produced by hygrophilous plants, suggests the possibility of locally
or seasonally humid conditions (Schrank & Mahmoud, 1998) and therefore, a
regional warm and semi-arid palaeoclimate is suggested to prevail during deposition
of the sediments but with a local humid condition developed near or at the site of
the well (Mahmoud & Deaf, 2007).
6. CONCLUSIONS
Berriasian to Albian sediments of the Siqeifa1-X well have been studied
previously by Mahmoud and Deaf (2007), where they gave a preliminary
interpretation of the palaeoenvironments. Here a detailed palynofacies analysis was
carried out and enabled the recognition of various palaeoenvironments of the
formations encountered, which corresponded to three major palynofacies types. PF-
1 represents the lower-middle Alam El Buieb Formation (samples 1-15) that was
deposited in a deltaic (prodelta) setting during a Berriasian-early Barremian
regression episode, but with its lower upper part (samples 16-21) deposited in an
inner shallow marine setting during a partial regain of local and global late
Barremian-Aptian transgression episodes, under prevailing dysoxic-anoxic to
suboxic-anoxic conditions. PF-2 represents the uppermost Alam El Buieb, Alamein,
and Dahab formations (late Barremian-Aptian), where the uppermost Alam El-
Buieb Formation (samples 22-26) was deposited in the distal bar of a prograding
delta accumulated during a minor local regression. However, the carbonate of the
Alamein Formation and the shale of the Dahab Formation were deposited in a saline
lagoon environment developed during a partial regain of the local early Aptian
marine transgression. Suboxic-anoxic to dysoxic-anoxic conditions are interpreted
to prevail during deposition of the PF-2 sediments. PF-3 represents the Kharita
Formation (Albian), which was deposited in a lagoon setting (samples 43-52)
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-47
changed upward into a deltaic environment (samples 53-56) due to a major marine
regression, under prevailing dysoxic-suboxic conditions.
Local pteridophyte vegetation on low lands near the borehole and conifers
on relatively dry hinterlands is interpreted to thrive under a regional warm and
relatively dry palaeoclimate. Possible seasonal dry periods may be developed during
deposition of the uppermost Alam El Buieb, Dahab and Alamein formations.
ACKNOWLEDGEMENT
We are grateful to authorities of the Egyptian General Petroleum Corporation for
providing samples and borehole Log. Thanks are due to the reviewers for their
helpful comments to improve the quality of the manuscript.
VI-48 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
Plate 1
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-49
The photomicrographs are published in Mahmoud & Deaf (2007). For full
reference to taxa refer to Mahmoud & Deaf (op. cit.).
Plate 1
(Magnification X500)
1, 6. Deltoidospora spp., 1, Slide S-31A: E.F. S48-4, 6, Slide S-36A: E.F. L11.
2. Triplanosporites sp., Slide S-31A: E.F. V41-3.
3, 20. Cicatricosisporites spp. 2, Slide S-04A: E.F. O49-4, 20, Slide S-05B: E.F. V32-2.
4. Tricolpites microreticulatus Belsky et al., 1965, Slide S-68A: E.F. X63-4.
5, 10. Balmeioposis limbatus (Balme) Archangelsky, 1979, 5, Slide S-39A: E.F. L25-4,
10, Slide S-39A: E.F. Q13-4.
7. Cicatricosisporites brevilaesuratus Couper, 1958, Slide S-02A: E.F. Y20.
8. Classopollis torosus (Reissinger) Balme, 1957, Slide S-46A: E.F. Z27.
9. Inaperturopollenites undulatus Weyland & Greifeld sensu Sultan (1987, fig. 3/28),
Slide S-12A: E.F. J22-3.
11. Arucariacites australis Cookson, 1947, Slide S-39A: E.F. Q39-1.
12. Spheripollenites sp., Slide S-05A: E.F. Z39-2.
13. Inaperturopollenites undulates Weyland & Greifeld sensu Sultan (1987, fig. 3/28),
Side S-12A: E.F. N27.
14. Afropollis zonatus Doyle et al., 1982, Slide S-39A: E.F. Z35-2.
15. Afropollis operculatus Doyle et al., 1982, Slide S-39A: E.F. N56-2.
16. Ovoidites parvus (Cookson & Dettmann) Nakoman, 1966, Slide S-45A: E.F. R47.
17. Biserial Microforaminiferal test linings, Slide S-39A: E.F. K25-2.
18, 19. Concavissimisporites punctatus (Delcourt & Sprumont) Brenner, 1963, 18,
Slide S-39B: E.F. X57-3, 19, Slide S-37A: E.F. V60-4.
21. Planispiral Microforaminiferal test linings, Slide S-02A: E.F. N56.
22-24. Ephedripites spp., 25, Slide S-37A: E.F. Z44, 26, Slide S-53B: E.F. X20, 27,
Slide S-33A: E.F. H34-3.
25. Duplexisporites generalis Deak, 1962, Slide S-30B: E.F. G34.
26. Duplexisporites sp., Slide S-35A: E.F. Y11-3.
VI-50 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
Plate 2
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-51
The photomicrographs are published in Mahmoud & Deaf (2007). For full
reference to taxa refer to Mahmoud & Deaf (op. cit.).
Plate 2
(Magnification X500 for 6, 8, 10, 12-19, and the others have magnification X250)
1. Structured phytoclast of probably gymnospermous plant, composed at least of four
gymnosperm tracheids (showing bordered pits in a four serial offset arrangement).
2. Amorphous organic matter (AOM).
3. Cuticular phytoclast showing regular rectangular cell outlines of probably
gymnospermous origin.
4. Membranous phytoclast of uncertain origin because of the lack of diagnostic
structure (membranous phytoclasts are thin, highly translucent, lack of internal
structure, and tend to be relatively large).
5. Black and brown striped tracheidal phytoclat.
6. Coronifera tubulosa Cookson & Eisenack, 1974, Slide S-49B: E.F. J16.
7. Structured tracheidal phytoclast of probably gymnospermous plant (each perforated
bordered pit with a concentric thickened zone)
8. Cyclonephelium cf. vannophorum Davey, 1969, Slide S-04B: E.F. X41-3.
9. Degraded terrestrially derived phytoclast showing destruction, with original outlines
preserved.
10. Oligosphaeridium complex (White) Davey & Williams, 1966, Slide S-40A: E.F.
Z37
11. Structured phytoclast derived from gymnosperm xylem ray tissue, showing a cross
hatching structure, with thickened ribs arranged approximately at right angle to each
other.
12. Odontochitina operculata (O.Wetzel) Deflandre & Cookson, 1955, Slide S-30A:
E.F. O26-3.
13. Circulodinium distinctum Deflandre & Cookson, 1955, Slide S-03A: E.F. Y45.
14. Pseudoceratium eisenackii (Davey) Bint, 1986, Slide S-17A: E.F. S14-1.
15, 17. Subtilisphaera senegalensis Jain & Millepied, 1973, 15, Slide S-39A: E.F. N17-
3, 17, Slide S-52A: E.F.X18.
16, 18. Oligosphaeridium pulcherrimum (Deflandre & Cookson) Davey & Williams,
1966, 16, Slide S-47B: E.F. H12-3, 18, Slide S-20A: E.F. S18-3.
19. Oligosphaeridium complex (White) Davey & Williams, 1966, Slide S-32A: E.F.
B43-4.
VI-52 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
Plate 3
1 PF-1
PF-2 2
3 PF-3
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-53
The photomicrographs are published in Mahmoud & Deaf (2007). For full
reference to taxa refer to Mahmoud & Deaf (op. cit.).
Plate 3
(Magnification X100)
1. Palynofacies (PF-1) dominated by brown wood and amorphous organic matter.
2. Palynofacies (PF-2) dominated by brown and black wood, with a diverse
assemblage of miospores as indicated by (Murospora florida, Deltoidospora and
Triplanosporites).
3. Palynofacies (PF-3) dominated by black wood and less abundant amorphous organic
matter.
REFERENCES
Abdel-Kireem, M.R., Schrank, E., Samir, A.M., Ibrahim M.I.A. (1993) Cretaceous
palaeoecology, palaeoclimatology and palaeogeography of the northern Western
Desert of Egypt. IN: Thorweihe U. & Schandelmeier H. (Eds.), Geoscientific
Research in Northeast Africa, Balkema-Rotterdam-Brookfield, 375-380.
Abdel-Kireem, M.R., Schrank, E., Samir, A.M., Ibrahim, M.I.A. (1996) Cretaceous
palaeoecology, palaeogeography, and palaeoclimatology of the northern Western
Desert, Egypt. Journal of African Earth Sciences, 22: 93-112.
Aboul Ela, N.M., Shaw, D., Ragab, S.E. (1996) Palynostratigraphy of the Bahariya
Formation in the subsurface of the Salam Oil Field, north Western Desert, Egypt.
Proceedings of 13th Petroleum Conference, Cairo, Egypt, 1: 381-400.
Al-Ameri, T.K., Al-Musawi, F.S., Batten, D.J. (1999) Palynofacies indications of
depositional environments and source potential for hydrocarbons: uppermost
Jurassic-basal Cretaceous Sulaiy Formation, southern Iraq. Cretaceous Research,
20: 359-363.
Al-Ameri, T.K., Al-Najar, T.K., Batten, D.J. (2001) Palynostratigraphy and
Palynofacies indications of depositional environments and source potential for
hydrocarbons: the Mid Cretaceous Nahr Umr and lower Mauddud formations,
Iraq. Cretaceous Research, 22: 732–742.
Al-Ameri, T.K., Al-Khafa, A.J., Zumberge, J. (2009) Petroleum system analysis of the
Mishrif reservoir in the Ratawi, Zubair, North and South Rumaila oil fields,
southern Iraq. GeoArabia, 14: 91-108.
Balme, B. E. (1957): Spores and pollen grains from the Mesozoic of Western Australia.
Australian Commomwealth Scientific and Industrial Research Organization.
Coal Research Section technical Commission, 25: 1-48.
Barakat, M.G., Darwish, M. (1987) Contribution to the lithostratigraphy of the Lower
Cretaceous sequence in Mersa Matruh area, North Western Desert, Egypt. Ain
Shams University Middle East Research Center, Earth Science Series, Cairo,
Egypt, 1: 48-66.
Batten, D.J. (1973) Use of palynologic assemblage types in Wealden correlation.
Palaeontology, 16: 1-40.
Batten, D.J. (1981) Palynofacies, organic maturation and source potential for
petroleum. IN: Brooks, J. (Ed.), Organic maturation studies and fossil fuel
exploration. Academic Press, London, p. 201–223.
Batten, D.J. (1982) Palynofacies, palaeoenvironments, and petroleum. Journal of
Micropaleontology, 1: 107–114.
VI-54 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
Batten, D.J. (1983) Identification of amorphous sedimentary organic matter by
transmitted light. IN Brooks, J. (Ed.) Petroleum Geochemistry and Exploration of
Europe. Geological Society of London Special Publication.
Batten, D.J. (1996) Palynofacies and palaeoenvironmental interpretation. IN: Jansonius,
J. & Mcgregor, D.C. (Eds.), Palynology: principles and applications. American
Association of Stratigraphic Palynologists, 3: 1011-1064.
Batten, D.J. (1999) Palynofacies analysis. IN: Jones, N. P. & Rowe, N.P. (Eds.), Fossil
Plants and Spores: modern techniques. Geological Society, London, p. 194-198.
Boggs, S, Jr. (2006) Principles of Sedimentology and Stratigraphy (4th edition) 96–97.
Pearson Prentice Hall, New Jersey. 662p.
Boulter, M.C., Riddick, A. (1986) Classification and analysis of palynodebris from the
Paleocene sediments of the Forties Field. Sedimentology, 33: 871–886.
Brenner, G.J. (1996) Evidence for the earliest stage of angiosperm pollen evolution: a
paleoequarorial section from Israel. IN Taylor, D.W. & Hickey, L.J. (Eds.)
Flowering Plant Origin, Evolution & Phylogeny. New York, Chapman & Hall.
Bujak, J.P., Barss, M.S., Williams, G.L. (1977) Offshore east Canada's organic type and
color and hydrocarbon potential. The Oil and Gas Journal, 75: 198-201.
Combaz, A. (1964) Les palynofacies. Revue de Micropaléontologie, 7: 205-218.
Couper, R.A. (1958) British Mesozoic microspores and pollen grains. A Systematic and
Stratigraphic Study. Palaeontographica, B, 103: 75-179.
Deaf, A.S. (2009) Palynology, palynofacies and hydrocarbon potential of the
Cretaceous rocks of northern Egypt. Published Ph.D. Thesis, Southampton
University, 348 pp.
Dow, W.G., Pearson, D.B. (1975) Organic matter in Gulf coastal sediments. Offshore
Technology Conference, Dallas, 1975.
Doyle, J.A. (1999) The rise of angiosperms as seen in the African Cretaceous pollen
record. IN HEINE, K. (Ed.) Third Conference on African Palynology.
Johannesburg 14-19 September, 1997, Balkema, Rotterdam.
Doyle, J.A., Jardine, S., Doerenkamp, A. (1982) Afropollis, a new genus of early
angiosperm pollen, with notes on the Cretaceous palynostratigraphy and
paleoenvironments of northern Gondwana. Bulletin des Centres de Recherches
Exploration-Production Elf Aquitaine, 6: 39-117.
Dybkjaer, K. (1991) Palynological zonation and palynofacies investigation of the
Fjerritslev Formation (Lower Jurassic - basal Middle Jurassic) in the Danish
Subbasin. Danmarks Geologiske Undersogelse serie A, 30, 150.
EGPC, (1992) Western Desert, Oil and Gas Fields. A Comprehensive Overview.
Egyptian General Petroleum Corporation, 431p.
Einsele, G. (1992) Sedimentary basins. Evolution, Facies, and Sediment Budget: Berlin,
Springer-Verlag, 628 pp.
El-Beialy, S.Y. (1994) Early Cretaceous dinoflagellate cysts and miospores from the
Mersa Matruh 1 borehole, north West Desert, Egypt. Qatar University Science
Journal, 14: 148-200.
El-Gezeery, M.N., Mohsen, S.M., Farid, M. (1972) Sedimentary basins of Egypt and
their petroleum prospects. Proceedings of the 8th Arab Petroleum Congress,
Algiers, 1–15.
El-Soughier, M.I., Mahmoud, M. S., Li J. (2010) Palynology and palynofacies of the
lower Cretaceous succession of the matruh2-1X borehole, northwestern Egypt.
Revista Española de Micropaleontologia, 42: 37-58.
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-55
Firth, J.V. (1993) Palynofacies and thermal maturation analysis of sediments from the
Nankai Trough. Proceedings of the Ocean Drilling Project, Scientific Results,
131: 57-69.
Ghorab, M.A., Ebeid, Z., Tawfik, N. (1971) On the stratigraphy of the northeastern
corner of the Western Desert. Ninth Annual Meeting of the Geological Society of
Egypt. Giza, Egypt.
Habib, D. (1979) Sedimentology of palynomorphs and palynodebris in Cretaceous
carbonaceous facies south of Vigo Seamount. Initial Reports of the Deep Sea
Drilling Project, 47: 451-467.
Habib, D. (1982) Sedimentary supply origin of Cretaceous black shales. IN Schlanger,
S.O. & Cita, M. B. (Eds.) Nature and Origin of Cretaceous Carbon-Rich Facies.
London, Academic Press.
Habib, D. (1983) Sedimentation-Rate-Dependent Distribution of Organic-Matter in the
North-Atlantic Jurassic-Cretaceous. Initial Reports of the Deep Sea Drilling
Project, 76: 781-794.
Hantar, G. (1990) North Western Desert. IN: Said, R. (Ed.) The Geology of Egypt,
Rotterdam, Balkema, 15: 293-319.
Harding, I.C. (1986) An Early Cretaceous dinocyst assemblage from the Wealden of
southern England. Palaeontology Special Paper, 35: 95-109.
Hellem, T., Kjemperud, A., Øvrebo, O.K. (1986) The troll field; geological/geophysical
model established by the PL085 group. IN Spencer, A.M. et al. (Eds.) Habitat of
Hydrocarbons on the Norwegian Continental shelf. Graham & Trotman, London,
pp. 217-38.
Hermina, M., Klitzesch, E., List, F.K. (1989): Stratigraphic lexicon and explanatory
notes to the geological map of Egypt: Conoco Corel and Egyptian General
Petrol. Corporation (Cairo).
Herngreen, G.F.W., Kedves, M., Rovnina, L.V., Smirnova, S.B. (1996) Cretaceous
palynofloral provinces: a review. IN Jansonius, J. & Mcgregor, D.C. (Eds.)
Palynology: Principles and Applications. Texas, American Association of
Stratigraphic Palynologists Foundation.
Hughes, N.F., Moody-Stuart, J.C. (1967) Palynological facies and correlation in the
English Wealden. Review of Palaeobotany and Palynology, 1: 259-268.
Ibrahim, M.I.A. (2002) Late Albian-middle Cenomanian palynofacies and
palynostratigraphy, Abu Gharadig-5 well, Western Desert, Egypt. Cretaceous
Research, 23: 775-788.
Kerdany, M.T., Cherif, O.H. (1990) Mesozoic. IN Said, R. (Ed.) The Geology of Egypt.
Rotterdam, Balkema.
Lamberson, M.N., Bustin, R.M. ,Kalkreuth, W. (1991) Lithotype (maceral) composition
and variation as correlated with paleo-wet land environments, Gates Formation,
north - eastern British Columbia, Canada. International Journal of Coal Geology,
18: 87–124.
Lister, J.K., Batten, D.J. (1988) Stratigraphic and paleoenvironmental distribution of
early Cretaceous dinoflagellate cysts in the Hurlands Farm Borehole, West
Sussex, England. Palaeontographica Abteilung B, 210: 8-89.
Lund, J.J., Pedersen, R.K. (1985) Palynology of the marine Jurassic formations in the
Vardekloft Ravine, Jameson Land, East Greenland. Bulletin of the Geological
Society of Denmark, 33: 371-399.
Mahmoud, M.S., Moawad, A.M.M. (1999) Miospore and dinocyst biostratigraphy and
paleoecology of the Middle Cretaceous (Albian–early Cenomanian) sequence of
VI-56 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
the Ghoroud-IX borehole, northern Western Desert, Egypt. IN 1st International
Conference on the Geology of Africa, Assiut, Egypt, 1: 1–13.
Mahmoud, M.S., Moawad, A.M.M. (2002) Cretaceous palynology of the Sanhur-1X
borehole, northern western Egypt. Revista Española de Micropaleontologia, 34:
129-143.
Mahmoud, M.S., Deaf, A.S. (2007) Cretaceous Palynology (Spores, Pollen and
Dinoflagellates cysts) of the Siqeifa 1-X borehole, Northern Egypt. Rivista
Italiana di Paleontologia e Stratigrafia,113: 203-221.
Marzi. R., Rullkötter, J. (1986) Organic matter accumulation and migrated
hydrocarbons in deep-sea sediments of the Mississippi fan and adjacent
intraslope basins, northern Gulf of Mexico. Mitteilungen Geologische
Paläontologisches Institute Universitat Hamburg, 60: 359-79.
Muller, J. (1959) Palynology of Recent Orinoco Delta and shelf sediments: reports of
the Orinoco Shelf expedition. Micropaleontology, 5: 1-2.
Murris,R.J. (1980) Facts and principles of world petroleum occurrence:hydrocarbon
habitat of the Middle East. IN Miall, A.D. (ed.), Facts and Principles of World
Petroleum Occurrence. Canadian Society of PetroleumGeologists, Memoir, 6:
765–800.
Mustafa, A.A., Tyson, R.V. (2002) Organic facies of Early Cretaceous synrift lacustrine
source rocks from the Muglad Basin, Sudan. Journal of Petroleum Geology, 25:
351-365.
Mutterlose, J., Harding, I. (1987) Phytoplankton from the anoxic sediments of the
Barremian (lower Cretaceous) of north-west Germany. Abhandlungen der
Geologischen Bundesanstalt (Vienna), 39: 177-215.
Nagy, J., Dypvik, H., Bjaerke, T. (1984) Sedimentological and paleontological analyses
of Jurassic North Sea deposits from deltaic environments. Journal of Petroleum
Geology, 7: 169-188.
Norton, P. (1967) Rock Stratigraphic Nomenclature of the Western Desert. Internal
Report. Pan American Oil Company, UAR, Cairo, Egypt.
Nichols, G. (2009) Sedimentology and stratigraphy, Second Edition (West Sussex:
Wiley-Blackwell), p. 419.
Obeid, F.L. (2003) Palynostratigraphy of the subsurface Jurassic–Lower Cretaceous
(Aptian) rocks from Zebieda IX Well and Gebel Rissu well, north Western
Desert, Egypt. Egyptian Journal of Geology, 47: 491–509.
Oboh-Ikuenobe, F.E., de Villiers, S.E. (2003) Dispersed organic matter in samples from
the western continental shelf of southern Africa: palynofacies assemblages and
depositional environments of late cretaceous and younger sediments.
Palaeogeography, Palaeoclimatology, palaeoecology, 201:67-88.
Playford, G. (1971) Palynology of the Lower Cretaceous (Swan River) strata of
Saskatchewan and Manitoba. Paleontology, 14: 533-565.
Pocklington, R., Leonard, J.D. (1979) Terrigenous organic mattter in sediments of the
St. Lawrence Estuary and the Saguenay Fjord. Journal of the Fisheries Research
Board of Canada, 36:1250-1255.
Pocock, S.A.J. (1982) Identification and recording of particulate sedimentary organic
matter. IN Staplin, D.J., Dow, W.G., Milner, C.W.D., O'connor, D.I., Pocock,
S.A.J., Van Gijzel, P., Welte, D.H., Yukler, M.A. (Eds.) How to Assess
Maturation and Paleotemperatures. Society of Economic Paleontologists and
Mineralogists, Short Course.
Magdy S. Mahmoud, Mohamed A. Masoud, Mohamed A.Tamam, and
Miran M. Khalaf
VI-57
Prauss, M. (1989) Dinozysten-stratigraphie und palynofazies im oberen Lias und
Dogger von NW-Deutschland. Palaeontographica Abteilung B, 214: 1-124.
Reyre, Y. (1973) Palynologie du Mesozoique Saharien. Mémoris du Muséum National
d’Histoire Naturelle, 27:1-284.
Robert, P. (1979) Classification of organic matter by means of fluorescence; application
to hydrocarbon source rocks. International Journal of Coal Geology, 1: 101–137.
Roncaglia, L. (2006) Revision of the palynofacies model of Tyson (1993) based on
recent high-latitude sediments from the North Atlantic. Facies, 52: 19-39
Said, R. (1990) Cretaceous paleogeographic maps. IN Said, R. (Ed.) The Geology of
Egypt, Rotterdam, Balkema. p. 439-449.
Schrank, E. (1990) Palynology of the clastic Cretaceous sediments between Dongola
and Wadi Muqaddam, northern Sudan. Berliner Geowissenschaftliche
Abhandlungen - Reihe A, 120: 149-168.
Schrank, E. (2001) Paleoecological aspects of Afropollis/elaterate peaks (Albian-
Cenomanian pollen) in the Cretaceous of Northern Sudan and Egypt. IN:
Goodman, D.K., Clarke, R.T. (Eds.) Proceeding of the IX International
Palynological Congress, Houston, Texas, 1996. American Association of
Stratigraphic Palynologists Foundation.
Schrank, E. (1994) Nonmarine Cretaceous palynology of northern Kordofan, Sudan,
with notes on fossil Salviniales (water ferns). Geologische Rundschau, 83: 773–
786.
Schrank, E., Mahmoud, M.S. (1998) Palynology (pollen, spores and dinoflagellates)
and Cretaceous stratigraphy of the Dakhla Oasis, central Egypt. Journal of
African Earth Sciences, 26:167-193.
Smyth, M., Jian, F.X., Ward, C.R. (1992) Potential petroleum source rocks in Triassic
lacustrine-delta sediments of the Gunnedah Basin, Eastern Australia. Journal of
Petroleum Geology, 15: 435-450.
Stancliffe, R.P.W. (1989) Microforaminiferal linings: their classification,
biostratigraphy and paleoecology, with special reference to specimens from
British Oxfordian sediments, Micropaleontology, 35: 337-352.
Summerhayes, C.P. (1987): Organic-rich Cretaceous sediments from the North
Atlantic. IN Brooks, J., Fleet, A.J. (Eds.), Marine petroleum source rocks.
Geological Society of London Special Publication, 26: 301-316.
Ten Haven, H.L., Littke, R., Rullkötter, J., Stein, R., Welte, D.H. (1990) Accumulation
rates and composition of organic matter in late Cenozoic sediments underlying
the active upwelling area off Peru. IN Suess, E., von Huene, R., et al., Proc.
ODP, Scientific Results, 112: 591-606.
Traverse, A. (1988): Paleopalynology. Unwin Hyman, Boston, 1-600.
Traverse, A. (2007) Paleopalynology, Dordrecht, Springer.
Tyson, R.V. (1984) Palynofacies investigation of Callovian (Middle Jurassic) sediments
from DSDP Site 534, Black-Bahama Basin, Western Central Atlantic. Marine
and Petroleum Geology, 1: 3-13.
Tyson, R. V. (1989) Late Jurassic palynofacies trends, Piper and Kimmeridge Clay
Formations, UK onshore and offshore. IN: Batter, D.J. , Keen, M.C. (Eds.)
Northwest European Microplaeontology and Palynology. Chichester, British
Micropalaeontological Society Series, Ellis Horwood.
Tyson, R.V. (1993) Palynofacies analysis. IN Jenkins, D.G. (Ed.) Applied
Micropaleontology. Kluwer Academic Publisher, Dordrecht, 153–191.
VI-58 Palynofacies Analyses and Palaeoenvironments of Some Lower Cretaceous Rocks...
Tyson, R.V. (1995) Sedimentary organic matter-Organic facies and palynofacies.
Chapman and Hall, London.
Vail, P.R., Mitchum, J.R.M., Thompson, S. (1977) Seismic stratigraphy and global
changes of sea level, Part 4: Global cycles of relative changes of sea level.
Seismic Stratigraphy - Application to Hydrocarbon Exploration. American
Association of Petroleum Geologists, Memoirs, 26: 83-97.
Van Bergen, P.F., Janssen, N.M.M., Alferink, M., Kerp, J.H.F. (1990) Recognition of
organic matter types in standard palynological slides. IN Fermont, W.J.J.,
Weegink, J.W. (Eds.), Proceedings of the International Symposium on Organic
Petrology. Mededelingen Rijks Geologische Dienst, 45: 9–21.
Watson, J. (1988) The Cheirolepidiaceae. IN Beck, C.B. (Ed.) Origin and Evolution of
Gymnosperms. New York, Columbia University Press.
WEPCO (1970) Final report and composite well log of the Siqeifa 1-X borehole.
Western Desert Operating Petroleum Company, Egypt.
Williams, G.L. (1992) Palynology as a palaeoenvironmental indicator in the Brent
Group, northern North Sea. IN Morton, A.C., Haszeldine, R.S., Giles, M.R. &
Brown, S. (Eds.) Geology of the Brent Group. Geolological Society of London
Special Publication
Zobaa, M.K., El-Beialy, S.Y., El-Sheikh, H.A., El Beshtawy M.K. (2013) Jurassic–
Cretaceous palynomorphs, palynofacies, and petroleum potential of the Sharib-
1X and Ghoroud-1X wells, north Western Desert, Egypt. Journal of African
Earth Sciences, 78: 51–65.
Zonneveld, K.A.F., Chen, L., Möbius, J., Mahmoud, M.S. (2009) Environmental
significance of dinoflagellate cysts from the proximal part of the Po-river
discharge plume (off southern Italy, Eastern Mediterranean), Journal of Sea
Research, 62: 189–213.