Content uploaded by Robert P. Speijer
Author content
All content in this area was uploaded by Robert P. Speijer
Content may be subject to copyright.
INTRODUCTION
The Danian and Selandian Stages are chronostratigraphi-
cally equivalent to the lower Paleocene and the lower upper
(“middle”) Paleocene, respectively (Berggren et al., 1995,
2000). In western Europe, an unconformity between the Danian
and Selandian Stages marks a sequence boundary in the Ceno-
zoic cycle charts (Se-1 of Hardenbol, 1994; Sel 1, Hardenbol et
al., 1998). According to Hardenbol et al. (1998) this sequence
boundary correlates with the sequence boundary between cycles
TA-1.3 and TA-1.4, which may have resulted from a eustatic
sea-level fall and subsequent rise (Haq et al., 1988). If this se-
quence boundary was indeed controlled by eustatic sea-level
change, then the southern Tethyan (North African) margin must
have recorded a similar sea-level history.
Tunisian and Libyan records do not provide support for a
eustatic sea-level fluctuation during the Danian-Selandian tran-
sition (Kouwenhoven et al., 1997), but several records from
Egypt seem to be in line with this part of the Haq et al. (1988)
curve. Lüning et al. (1998) studied the stratigraphy of many Pa-
leocene outcrops in eastern Sinai (Egypt), and correlated the lo-
cal sequence boundary ThSin-1, with Sel 1 of Hardenbol et al.
(1998) and with the TA1.3/TA1.4 sequence boundary of Haq et
al. (1988). In the Aweina section (Eastern Desert, Egypt), Spei-
jer and Schmitz (1998) documented a high-amplitude sea-level
fluctuation from a succession of benthic foraminiferal assem-
Geological Society of America
Special Paper 369
2003
Danian-Selandian sea-level change and biotic excursion
on the southern Tethyan margin (Egypt)
Robert P. Speijer
Department of Geosciences (FB5), Bremen University, P.O. Box 330440, 28334 Bremen, Germany
ABSTRACT
A study on Danian to Selandian foraminifera (planktic/benthic ratios, benthic as-
semblages) in 23 sections on a N-S transect in eastern Egypt documents a transient bi-
otic excursion associated with sea-level fluctuation at ∼∼60.5 Ma (Subbiochron P3a). In
southern areas, the inner to middle neritic (30–70 m) Neoeponides duwi assemblage
expanded into deeper parts of the shelf (∼∼70–250 m), temporarily replacing the Anom-
alinoides umboniferus and Angulogavelinella avnimelechi assemblages. In the deeper
parts of the basin (∼∼400–600 m) in the northern part of the transect, the Gavelinella
beccariiformis assemblage appears to have been persistent throughout the studied time
interval. Biofacial and sedimentologic data suggest a relative sea-level fluctuation, pos-
sibly with an amplitude of 50–100 m, which may correlate with a eustatic sea-level cy-
cle during the Danian-Selandian transition. During early sea-level rise, total organic
carbon–enriched, partially laminated sediments, containing abundant fish-remains
and planktic foraminifera (>>99.5% planktics), were deposited, reflecting oxygen defi-
ciency at the seafloor. The patterns of biotic and sea-level change at the Danian-Se-
landian transition strongly resemble those across the Paleocene-Eocene Thermal Max-
imum in the same basin, suggesting similar operative processes. Considering the close
coincidence with a recently postulated brief period of oceanic warming at 60.5 Ma, the
question arises whether the observed patterns in Egypt could in part be related to a
global warming event, similar to the Paleocene-Eocene Thermal Maximum.
275
Speijer, R.P., 2003, Danian-Selandian sea-level change and biotic excursion on the southern Tethyan margin (Egypt), in Wing, S.L., Gingerich, P.D., Schmitz, B.,
and Thomas, E., eds., Causes and Consequences of Globally Warm Climates in the Early Paleogene: Boulder, Colorado, Geological Society of America Special
Paper 369, p. 275–290. © 2003 Geological Society of America.
blages within the Danian-Selandian transition, and tentatively
correlated it with Danian-Selandian sequence boundary Se-1 of
Hardenbol (1994).
The foraminiferal succession in Aweina included the tran-
sient occurrence of the shallow water Discorbis (=Neoeponides)
duwi assemblage between deeper shelf benthic assemblages
(Speijer and Schmitz, 1998). New observations on Danian-
Selandian benthic foraminiferal assemblages from 23 sections
on a N-S transect in eastern Egypt reveal the incursion of the
Neoeponides duwi assemblage in other sections in the southern
part of the transect. In this paper, I present a summary of these
observations, provide a new view on the relationship between
biotic and sea-level patterns during the Danian-Selandian tran-
sition, compare these with those related to the Paleocene-
Eocene Thermal Maximum in the same basin, and speculate on
possible implications from this comparison.
Danian-Selandian transition in the type region, Denmark
In its type region, Denmark, Danian chalks and limestones
are unconformably overlain by Selandian greensands and marls
(e.g., Thomsen and Heilmann-Clausen, 1985). This transition to
more terrestrially influenced deposition terminated a >35 m.y.
period of hemipelagic carbonate deposition in the Danish basin
276 R.P. Speijer
Figure 1. Lithostratigraphy, biostratigraphy, and sequence stratigraphy
of the Danian-Selandian transition in the type region, Denmark. Bio-
stratigraphic terminology as adopted in Berggren et al. (2000). Se-
quences TA1.3/1.4 after Haq et al. (1988) and sequence boundary
Sel 1 after Hardenbol et al. (1998). PF—planktic foraminifera; CN—
calcareous nannofossils.
(Håkansson et al., 1974; Schmitz et al., 1998). This change in
depositional regime between 60 and 61 Ma is related to the
opening of the northeastern Atlantic and the uplift of west Eu-
ropean landmasses (Berggren, 1994). Determining the exact
biostratigraphic positions of the bounding surfaces of the un-
conformity marking the Danian-Selandian boundary in the type
region, Denmark (Fig. 1), has proven difficult. Age and duration
of the unconformity vary geographically, but there is general
consensus that the top of the Danian correlates with a level
within calcareous nannofossil Zone NP4 and planktic fora-
miniferal Subzone P1c or Zone P2 (e.g., Bignot et al., 1997).
The base of the Selandian correlates with a level in the upper
Figure 2. Location map with sections studied (triangles). Numbers re-
fer to the following localities: (1) a transect composed of four sections
across the Areif en Naqa anticline; (2) eight sections west of Taba; (3)
a transect composed of five sections south of the Galala platform. See
Table 1 for biostratigraphic information and references.
long
half of Zone NP4 or the lower part of Zone NP5 (Thomsen and
Heilmann-Clausen, 1985; Thomsen, 1994; Stouge et al., 2000).
Foraminifera indicative of Subzone P3a are associated with the
base of the Selandian (Stouge et al., 2000), and this subzone
ought to have no stratigraphic overlap with Zone NP5 (Berggren
et al., 1995, 2000), so that it is plausible that the base of the
Selandian correlates with the top part of Zone NP4 and not with
Zone NP5. The stratigraphic gap at the Danian-Selandian
boundary in the type region thus spans an interval within Zone
NP4, correlative with at least the upper part of Zone P2 to the
lower part of Subzone P3a. Berggren (1994) and Berggren et al.
(1995, 2000) proposed to correlate the Danian-Selandian
boundary with the P2/P3 zonal boundary, with an estimated age
of 60.9 Ma, whereas Hardenbol et al. (1998) estimated the age
for sequence boundary Sel 1 in western Europe at 60.7 Ma
(lower Subzone P3a). Awaiting formal decision of the strati-
graphic position of the Danian-Selandian boundary, I refer to the
sea-level fluctuation recorded at Gebel Aweina within Subzone
P3a (Speijer and Schmitz, 1998), correlative with Sel 1 of Hard-
enbol et al. (1998), as a Danian-Selandian transition event.
Geological setting
The sections studied are located in the Eastern Desert and
in Sinai (Fig. 2, Table 1). This region was part of an extensive
epicontinental basin—with various subbasins—covering Egypt
during the Paleocene (Fig. 3). The area is traditionally subdi-
vided into two main structural units, the so-called stable shelf
Danian-Selandian sea-level change and biotic excursion 277
also known as Nile Basin in the south, and the unstable shelf,
also known as the Syrian Arc, in the north (Said, 1962; Shahar,
1994; Tawadros, 2001). The Nile Basin experienced little struc-
tural deformation during the early Paleogene, whereas the Syr-
ian Arc is characterized by a fold belt that has been tectonically
active since the Late Cretaceous (Shahar, 1994). During Danian-
Selandian times, the southern margin of the Nile Basin was sit-
uated close to the present southern border of Egypt (Luger,
1988). Most of the area north of Aswan was characterized by
hemipelagic marl and clay deposition in a generally northwest
deepening basin. Uplifted areas of the Syrian Arc in northern
Egypt (e.g., the Galala platform) and the local high of Abu Tar-
tur in central Egypt interrupt this generally deepening trend.
More terrestrially influenced deposition (deltaic, coastal) and
phases of erosion characterized the basin’s southern margin
(Hendriks et al., 1985, 1987; Luger, 1985, 1988; Hewaidy,
1994). The microfossil material from hemipelagic parts of the
basin studied here documents Danian-Selandian paleodepths
ranging from ∼70–150 m (Gebel Duwi) to ∼400–600 m (Sinai).
MATERIAL AND METHODS
Samples from 23 sections in eastern Egypt (Table 1, Fig. 4)
were collected during the last two decades by several teams from
the Universities of Berlin, Bremen, Gothenburg and Utrecht in
cooperation with partners in Egypt. In order to obtain fresh rock,
the samples were generally collected from 10 to 30-cm-deep
trenches or holes along the outcrop sections. Standard micropa-
TABLE 1. STRATIGRAPHIC DATA AND PALEODEPTH OF STUDIED SECTIONS
Profile Stratigraphy Paleodepth* Reference to stratigraphic data
Areif en Naqa, section A1b NP2–NP3 400–600 m Lüning (1997)
Areif en Naqa, section A5 NP2–NP3 400–600 m Lüning (1997)
Areif en Naqa, section A8 NP2–NP5 400–600 m Lüning (1997)
Areif en Naqa, section W NP3–NP6 400–600 m Lüning (1997)
Bir Hasana NP3–NP5 400–600 m Lüning (1997)
Sheikh Attiya NP1–NP6 400–600 m Lüning (1997); Lüning et al. (1998)
Gebel Misheiti NP1–NP6 400–600 m Lüning (1997); Lüning et al. (1998)
West Themed NP3–NP4 400–600 m Lüning (1997); Lüning et al. (1998)
Taba NP3–NP4, NP6 400–600 m Lüning (1997); Lüning et al. (1998)
Wadi Gureis NP1–NP3, NP6 400–600 m Lüning (1997); Lüning et al. (1998)
Egma Plateau NP3–NP6 400–600 m Lüning (1997); Lüning et al. (1998)
Gebel Umm Mafrud NP3–NP6 400–600 m Lüning (1997); Lüning et al. (1998)
North Nuweiba NP3–NP5 400–600 m Lüning (1997); Lüning et al. (1998)
Wadi Nukhl P1a–P4 400–600 m Anan (1992); this paper
Saint Paul 9 NP1–NP5 400–600 m Scheibner (2001); Scheibner et al. (2001)
Bir Dakhl 2 NP3–NP5 400–600 m Scheibner (2001); Scheibner et al. (2001)
Bir Dakhl 3 NP3–NP5 400–600 m Scheibner (2001); Scheibner et al. (2001)
Wadi Tarfa 1 NP2–NP6 400–600 m Scheibner (2001); Scheibner et al. (2001)
Wadi Tarfa 2 NP4–NP6 400–600 m Scheibner (2001); Scheibner et al. (2001)
Gebel Qreiya P1a–P4 150–250 m Luger et al. (1998) ); this paper
Gebel Nezzi P1c–P4 150–250 m This paper
Gebel Aweina P1c–P4 150–250 m Speijer and Schmitz (1998)
Gebel Duwi P1b–P4 70–150 m Faris (1984); this paper
Note:
Most sections range higher into the upper Paleocene and lower Eocene.
*Paleodepth estimates in this study.
long
278 R.P. Speijer
Figure 3. Reconstructed Paleocene paleogeography, lithofacies distri-
bution and paleobathymetry (no correction for opening of Red-Sea rift).
Triangles are sections studied (Fig. 2). Thick dashed grey line separates
tectonically stable Nile Basin from tectonically active Syrian Arc. Ar-
rows indicate general orientation of double-plunging anticlines (largely
submarine swells; schematic) of the Syrian Arc. Isobaths are based on
bio- and lithofacies distributions. Carbonate platforms (Abu Tartur and
Galala) represent elevated structures on the deeper shelf. Lithofacies
distribution modified from Luger (1988) with inclusion of data dis-
cussed in this study.
leontologic sample-processing procedures were employed (e.g.,
Speijer et al., 1996) and the size fraction larger than 125 µm was
used for foraminiferal analysis. Stratigraphic distribution and
compositional data of the benthic foraminiferal assemblages
were determined qualitatively. Only the main biotic patterns are
discussed here.
Assemblages from beds directly overlying the Cretaceous-
Paleogene boundary (e.g., Subzone P1a in Gebel Qreiya and
Wadi Nukhl) containing large proportions of reworked Maas-
trichtian foraminifera were disregarded. Planktic/benthic (P/B)
ratios, expressed as percentage planktics, were determined for
the southern Eastern Desert sections (Tables 2, 3). The terms
‘neritic’ and ‘bathyal’are used as representing paleodepths less
than and in excess of ∼200 m, respectively (Van Morkhoven et
al., 1986). Note however, that the continental slope was situated
north of the epicontinental basin studied (Mart, 1991).
Total organic carbon (TOC) and total carbon (C
tot
) con-
tents were measured on homogenized samples from Gebel
Nezzi and Gebel Qreiya using Leco elemental analyzer facili-
ties at Bremen University. TOC content (precision of measure-
ment ±3%) was measured with a Leco CS-300 and C
tot
with a
Leco CS-200 (precision of measurement ±3%). CaCO
3
content
(Table 2) was calculated from these measurements through:
CaCO
3
= 8.3333*(C
tot
-TOC).
LITHOSTRATIGRAPHY AND BIOSTRATIGRAPHY
In the study area, the Danian and Selandian Stages are rep-
resented by the upper part of the Maastrichtian-Paleocene
Dakhla Formation (Said, 1962, 1990) (Fig. 5). This formation
consists of rather monotonous brownish to grey marls and shales
with occasional intercalated thin marly limestone beds. In Sinai,
age-equivalent marls and shales are sometimes referred to as
Esna Formation, overlying the Maastrichtian Sudr Formation
(e.g., Said, 1990; Lüning et al., 1998). The Dakhla Formation is
usually overlain by Thanetian limestones and chalks of the
Tarawan Formation. In the Sinai sections, however, the Tarawan
Formation is usually just a few meters thick or is absent. In the
latter case, there is no clear lithologic boundary between the
Dakhla Formation and the Esna Formation (s.s.: Thanetian–
Ypresian marls and shales overlying the Tarawan Formation
[Scheibner et al., 2001]). Danian and Selandian marginal marine
successions in the Western Desert are represented by the Kurkur
Formation. South of the Abu Tartur platform, this formation in-
terfingers with marls of the basinal Dakhla Formation.
The studied interval spans planktic foraminiferal Zone P1
to the lower part of Zone P4, corresponding to calcareous nan-
nofossil zones NP1-NP6 (Berggren et al., 1995, 2000). In this
study, because of the rarity of the P4 zonal marker Globanom-
alina pseudomenardii, the base of Zone P4 is approximated by
the lowest occurrence of Morozovella velascoensis, a species
traditionally thought to appear approximately simultaneously
with G. pseudomenardii (e.g., Blow, 1979; Toumarkine and
Luterbacher, 1985). Recent studies, however, suggest that the
Danian-Selandian sea-level change and biotic excursion 279
Figure 4. Biostratigraphic ranges of
sections studied. Dashed lines indicate
stratigraphic gaps. Ranges of the
Galala transect (3) and all Sinai sec-
tions but Wadi Nukhl are based on cal-
careous nannofossil data (Table 1). In-
consistencies may exist with equivalent
planktic foraminiferal zonal ranges
(e.g., Wadi Gureis, Lüning et al., 1998).
Biostratigraphic calibration of other
sections is primarily based on planktic
foraminifera. Bio- and chronostrati-
graphic scheme after Berggren et al.
(2000). Grey band spanning the Dan-
ian-Selandian transition indicates the
approximate extent of the stratigraphic
gap between the two stages in Denmark
(Fig. 1). Ms—Maastrichtian; Th—
Thanetian; Tar—Tarawan; A.e. Naqa—
Areif en Naqa.
lowest occurrence of M. velascoensis is within Subzone P3b
(Olsson et al., 1999), and thus the stratigraphic range of Subzone
P3b may be underestimated in the present study. Detailed bios-
tratigraphic data of most of these sections can be found in pre-
vious reports (Table 1, Fig. 4). For Gebel Qreiya and Gebel
Nezzi, new biostratigraphic data are presented in Table 2.
RESULTS
Sedimentology, CaCO
3
, TOC
Sedimentary structures in the monotonous grey to grey-
brown marl successions of the Dakhla Formation are rare, par-
ticularly in the successions in Sinai deposited at greater depths.
In the Eastern Desert sections of Aweina, Nezzi, and Qreiya, the
marls generally contain between 15 and 60% CaCO
3
(Table 2;
Speijer and Schmitz, 1998). At 25–40 m above the Cretaceous-
Paleogene boundary in these sections, an up to several-dm-thick
dark-brown, foraminifera-rich marl bed is intercalated within
Subzone P3a (Table 4). This partly laminated bed, containing
abundant fish remains and planktic foraminifera, in part pre-
served as pyritic molds, seems to fill in an inconspicuous undu-
lating channel-like surface in the marls. In Aweina, immediately
overlying this bed common pyritic macrofossils are observed. In
the Duwi section, 10 brownish more indurated beds are present
in the Paleocene part of the Dakhla Formation. One of these,
containing abundant secondary gypsum veins, was not sampled,
but is situated in the same biostratigraphic position as the dark-
brown marl beds in the other Eastern Desert sections. In the
overlying interval, shark teeth, gastropods, bivalves, solitary
corals and crinoid stems are common.
The TOC contents in “background marls” ranges generally
between 0.1% and 0.2% in Nezzi and 0.1% and 0.3% in Qreiya
(Table 2). The anomalous dark-brown bed in these sections,
however, yields 0.75% and 2.0% TOC, respectively. This bed is
sandwiched within shale beds with <10% CaCO
3
, of which the
overlying one also has slightly elevated TOC contents (0.95% in
Qreiya and 0.27% in Nezzi).
Planktic/benthic (P/B) ratios and planktic
foraminiferal assemblages
P/B ratios from Zone P3 (Table 3) represent the total range
of P/B ratios observed in the Dakhla Formation very well. P/B
ratios of the lower and upper parts of the Dakhla Formation in
Nezzi and Qreiya are listed in Table 2 for comparison. Most P/B
ratio values in Zone P3 fall within the range between 70% and
98% planktics. There appears to be no distinct gradient in P/B
ratios from the shallower to the deeper sections. More signifi-
cant are large variations within individual sections. Whereas in
the Galala area P/B ratios <50% planktics are rare, these are
more common in the Sinai sections and particularly in the
southern Eastern Desert sections. In Qreiya and Nezzi, anom-
alous low P/B ratios below 20% planktics are generally associ-
ated with low-carbonate sediments. In combination with low
absolute numbers of generally poorly preserved foraminifera,
numerous fragments, large proportions of agglutinated and
thick-shelled calcareous taxa, these low P/B ratios are an indi-
cation of postmortem dissolution. Loss of calcareous tests as-
sociated with reduced P/B ratios is observed in samples from
all regions, but is particularly prominent within Zone P3 in the
Aweina, Nezzi and Qreiya sections, especially in the shale beds
TABLE 2. FORAMINIFERAL AND GEOCHEMICAL
DATA OF GEBEL QREIYA AND GEBEL NEZZI
Level* % % %
Profile Sample (m) Biozone Planktics TOC CaCO
3
Gebel Qreiya 271185/30 54 P4 94.3 N.D. N.D.
271185/31 51 P4 98.0 0.21 81.6
271185/32 48 P4 64.1 0.20 63.8
271185/33 46.5 P4 48.7 0.15 42.9
271185/34 44.5 P4 59.9 0.14 54.4
271185/35 42 P4 63.1 0.18 50.4
271185/36 40 P4
†
67.4 0.34 46.4
271185/37 37.5 P3b 96.7 0.18 30.3
271185/38 34.5 P3b 92.9 0.16 35.8
271185/39 32 P3a 87.8 0.34 15.2
271185/40 31.6 P3a 22.2 0.95
§
7.7
271185/41 31.4 P3a 99.5 2.02
§
19.5
271185/42 31 P3a 0 # 0.32
§
5.8
271185/43 29 P3a 90.0 0.25 35.0
271185/44 26.5 P3a 85.3 0.22 15.4
271185/45 24 P2 93.5 0.24 24.1
271185/46 22 P2 94.0 0.24 23.6
281185/35 21 P2 90.9 0.12 27.4
281185/36 19 P1c 91.2 0.07 29.7
281185/37 17 P1c 86.9 0.07 35.2
281185/38 14.5 P1c 92.0 0.14 55.8
281185/26 13.5 P1c 75 0.10 58.5
281185/25 12 P1c 86 0.08 53.2
281185/24 10 P1b 69 0.08 52.8
281185/23 9.5 P1b 81 0.09 54.7
281185/22 8.0 P1b 47 N.D. N.D.
281185/21 5.5 P1b 65 0.02 57.2
281185/20 3.5 P1b 10 0.10 12.3
Gebel Nezzi 51285/28 66 P4 80.3 0.06 81.9
51285/27 61.5 N.D. 77.6 0.06 77.7
51285/26 59.5 N.D. 63.0 0.06 72.1
51285/25 57.5 N.D. 42.9 N.D. N.D.
51285/24 54 P4 92.5 0.06 78.7
51285/23 50 P4
†
90.1 0.14 79.6
51285/22 46 P3b 90.7 0.08 44.6
51285/21 42 P3b 93.3 0.11
§
44.7
51285/20 38.5 N.D. 1.9 0.27 1.9
51285/19 38 P3a 99.7 0.75
§
20.2
51285/18 37.5 N.D. 0 # 0.10 1.8
51285/17 34 P3a 85.6 0.12
§
16.9
51285/16 31.5 P2 86.5 0.08 25.5
51285/15 29.5 P2 87.0 0.14 22.2
51285/14 27 N.D. 92.3 0.11 30.2
51285/13 25 N.D. 84.1 0.14 30.5
51285/12 24.5 N.D. 90.1 0.15 44.4
51285/11 24 N.D. 66.1 0.10 42.8
51285/10 21.5 N.D. 85.5 0.10 49.6
51285/9 19.5 N.D. 81.9 0.15 63.0
51285/8 15 N.D. 25.9 0.14 46.8
51285/7 11 N.D. 74.6 0.21 53.4
51285/6 8.5 P1c 53.0 0.16 51.0
51285/5 7 N.D. 12.3 0.30 37.2
51285/4 5 N.D. 10.9 0.41 6.9
51285/3 2.5 N.D. 7.9 N.D. N.D.
51285/2 1.5 N.D. 0.0 0.37 1.8
Note:
Boldface data from anomalous dark-brown marl bed. N.D.—No data.
*Meters above Cretaceous-Paleogene boundary.
†
The base of Zone P4 is approximated by the lowest occurrence of
M. velascoensis.
§
Average value from two sub-samples.
#
Dissolution residues. Rare planktics only preserved as pyritic molds. Benthic assemblage consists
of agglutinated taxa and fragments of thick-shelled calcareous taxa (Nodosarians).
TABLE 3. PERCENTAGE PLANKTICS (%P) WITHIN ZONE P3 IN STUDIED SECTIONS
Sinai * Galala area* Southern Eastern Desert
Profile Sample %P Profile Sample % P Profile Sample %P
Areif en Naqa A8-18 97 St Paul 9 S9-58 92.1 Gebel Qreiya 271185/37 96.7
A8-17 94 S9-57 95.5 271185/38 92.9
A8-16 93 S9-56 95.4 271185/39 87.8
S9-55 96.2 271185/40 22.2
Areif en Naqa W1-11 59 S9-54 96.3 271185/41 99.5
W1-10 63 S9-53 94.2 271185/42 0
†
W1-9 89 S9-52 93.3 271185/43 90.0
W1-8 72 S9-51 94.7 271185/44 85.3
W1-7 61 S9-50 93.4
W1-6 98 S9-49 96.5 Gebel Nezzi 51285/23 90.1
W1-5 88 51285/22 90.7
W1-4 77 Bir Dakhl 2 D2-48 81.6 51285/21 93.3
W1-3 90 D2-47 87.0 51285/20 1.9
W1-2 87 D2-45 93.7 51285/19 99.7
D2-46 93.0 51285/18 0
†
Sheikh Attiya C1-29 73 D2-44 92.2 51285/17 85.6
C1-28 76 D2-43 91.0 51285/16 86.5
C1-27 85 D2-42 91.4
C1-26 86 D2-41 96.6 Gebel Aweina O95 + 750 cm 87.3
C1-25 73 D2-40 86.1 O95 + 600 cm 92.7
C1-24 85 D2-39 97.3 O95 + 450 cm 96.3
C1-23 21 D2-38 97.9 O95 + 400 cm 94.6
C1-22 67 D2-37 89.0 O95 + 275 cm 91.6
C1-21 83 D2-36 85.8 O95 + 175 cm 81.4
C1-20 97 D2-35 90.0 O95 + 70-80 cm 94.2
D2-34 82.3 O95 + 65—70 cm 87.3
Gebel Misheiti F1-43 82 D2-32 88.9 O95 + 55—60 cm 88.5
F1-42 88 D2-33 47.2 O95 + 19—24 cm 55.4
F1-41 78 D2-31 76.0 O95 + 0—2 cm 99.8
F1-40 95 D2-30 84.8 O95—5—8 cm 70.4
O95—9—15 cm 27.8
West Themed K1-15 94 Bir Dakhl 3 D3-36 92.1 O95—18—25 cm 68.8
D3-35 84.6 O95—30—35 cm 78.3
Taba M1-36 97 D3-34 80.1 O95—90—100 cm 44.3
M1-35 88 D3-33 94.7 O95—200 cm 72.4
M1-34 96 D3-32 94.9 O95—300 cm 76.3
D3-31 96.0 O95—400 cm 87.6
Wadi Gureis P1-30 95 D3-30 93.8
D3-29 90.3 Gebel Duwi DU95D/S+41 97.6
Egma Plateau Q1-12 98 D3-28 88.3 DU95D/S+40.5 95.1
Q1-11 53 D3-27 98.8 DU95D/S+40 70.0
D3-26 84.3 DU95D/S+39A 67.5
Gebel Umm Mafrud R1-8 52 DU95D/S+39 86.9
R1-7 66 Wadi Tarfa 1 T1-42 98.8 DU95D/S+38 83.1
R1-6 79 T1-41 97.3 DU95D/S+37 81.3
R1-5 97 T1-40 95.8
R1-4 89 T1-39 94.0
R1-3 97 T1-38 94.6
R1-2 97 T1-37 94.8
T1-36 96.1
North Nuweiba T1-14 45 T1-35 90.7
T1-13 77 T1-34 68.3
T1-12 81 T1-33 90.3
T1-11 96 T1-32 92.4
T1-10 94 T1-31 86.9
T1-9 70
T1-8 93 Wadi Tarfa 2 T2-11 56.6
T1-7 89 T2-10 50.0
T2-9 89.4
Wadi Nukhl S718 98 T2-8 95.7
S716 95 T2-7 88.8
T2-6 95.8
T2-5 98.0
T2-4 94.5
T2-3 87.1
T2-2 82.7
*Data from Sinai except for Wadi Nukhl from Lüning (1997) and data from Galala area from Scheibner (2001).
†
Dissolution residues. Rare planktics only preserved as pyritic molds. Benthic assemblage consists of agglutinated taxa and fragments of thick-
shelled calcareous taxa (Nodosarians).
encompassing the anomalous dark-brown marl bed (0%–22%
planktics). In contrast, the dark-brown bed itself, with >99.5%
planktics, contains the highest P/B ratios, observed in all stud-
ied material.
Planktic foraminiferal assemblages in Zone P3 are diverse
with most Paleocene genera like Morozovella, Subbotina, Para-
subbotina, Praemurica, Igorina, and Globanomalina well rep-
resented. In contrast, samples from the dark-brown bed with P/B
ratios of >99.5% planktics contain a poorly diverse planktic as-
semblage, largely constituted by nonkeeled genera with muri-
cate and praemuricate tests, such as Praemurica and Acarinina.
Particularly striking is the near absence of large morozovellids
(M. angulata, M. conicotruncata), which are typical for plank-
tic assemblages in Zone P3 in eastern Egypt. Samples from the
interval overlying the dark-brown bed in Aweina also lack mo-
rozovellids and contain relatively large numbers of Igorina tad-
jikistanensis.
Danian-Selandian benthic foraminiferal assemblages
Three main Danian-Selandian benthic foraminiferal assem-
blages characterize three bathymetric regimes from ∼70–150 to
∼400–600 m in the studied part of the basin (Fig. 6). The bathy-
metric interval between ∼250 and ∼400 m (situated between
Gebel Qreiya and the Galala transect) is not covered in this
study. Shallower assemblages, characterizing deposition at up to
∼70 m depth, were described from southern Egypt (Hewaidy,
1994; Schnack, 2000).
282 R.P. Speijer
Figure 5. Schematic lithostratigraphic
framework of the Paleocene in a north-
east-southwest transect across Egypt.
Only main lithostratigraphic units and
lithologies are indicated and the lateral
extent of marginal facies in southwest is
exaggerated. Hiatuses other than the
one spanning the Cretaceous-Paleogene
boundary are not indicated. Cret.—Cre-
taceous; Eoc.—Eocene; Ms—Maas-
trichtian; Da—Danian; Se—Selandian;
Th—Thanetian; Yp—Ypresian; Fm.—
Formation. Drawing after Luger (1985),
Hendriks et al. (1987), and Said (1990).
TABLE 4. DETAILED DATA ON SAMPLES CONTAINING THE
NEOEPONIDES DUWI
ASSEMBLAGE
%%%
Profile Sample Subzone Planktics TOC CaCO
3
Lithology Macrofossils
Gebel Qreiya 271185/40 P3a 22.2 0.95* 7.7 Dark-grey shale N.D.
271185/41 P3a 99.5 2.02* 19.5 Dark-brown marl N.D.
Gebel Nezzi 51285/20 P3a 1.9 0.27 1.9 Grey shale N.D.
51285/19 P3a 99.7 0.75* 20.2 Dark-brown marl N.D.
Gebel Aweina
†
O95 + 19—24 cm P3a 55.4 N.D. N.D. Grey marl Mollusks
O95 + 0—2 cm P3a 99.8 N.D. N.D. Dark-brown marl No
O95 — 5–8 cm P3a 70.4 N.D. N.D. Grey marl No
O95 — 9–15 cm P3a 27.8 N.D. N.D. Grey marl No
O92 + 26 m P3a 10.9 N.D. 13 Grey shale N.D.
O92 + 25 m P3a 2.9 N.D. N.D. Grey shale N.D.
Gebel Duwi DU95D/S+40 P3a 70.0 N.D. N.D. Grey shaley marl No
DU95D/S+39A P3a 67.5 N.D. N.D. Grey marl Shark teeth, mollusks, corals
DU95D/S+18 P1b 82.5 N.D. N.D. Dark-grey shaley marl No
DU95D/S+12 P1b 92.5 N.D. N.D. Brown-grey marl No
Note:
N.D.—No data.
*Average value derived from two sub-samples.
†
Data on O92 samples of Aweina from Charisi and Schmitz (1995) and Speijer and Schmitz (1998). The range of the two O92 samples corre-
sponds to the interval from ~20 cm below to ~30 cm above the dark-brown marl bed.
Anomalinoides umboniferus assemblage. The Anomali-
noides umboniferus assemblage in Gebel Duwi consists, besides
the common nominative species, of various Anomalinoides spp.
(A. cf. midwayensis, A. praeacutus), Cibicidoides spp. (C.
pseudoacutus, C. rigidus), Lenticulina spp., Bulimina spp. (B.
midwayensis, B. strobila), Siphogenerinoides eleganta, Valval-
abamina depressa, Oridorsalis plummerae, Osangularia plum-
merae, Loxostomoides applinae, and Gyroidinoides spp. Deep-
sea taxa such as Gavelinella beccariiformis, Nuttallides
truempyi, Gyroidinoides globosus, and Bulimina trinitatensis
are absent and deep outer neritic taxa such as Angulogavelinella
avnimelechi, Anomalinoides susanaensis, and Anomalinoides
affinis rarely occur in this assemblage. The absence of deeper
water species in combination with fairly high P/B ratios (aver-
age ∼85% planktics) suggests water depths ranging from ∼70 to
150 m (middle neritic to shallow outer neritic) for this assem-
blage. This assemblage is also found in a 1-m-thick interval im-
mediately underneath the incursion of the Neoeponides duwi as-
semblage (see below) at Aweina (Speijer and Schmitz, 1998).
Angulogavelinella avnimelechi assemblage. The Aweina,
Nezzi, and Qreiya sections are characterized by the Angulogave-
linella avnimelechi assemblage. This assemblage is generally
composed of most species of the Anomalinoides umboniferus as-
semblage listed above, but also contains larger numbers of
trochamminids and deep outer neritic taxa like A. avnimelechi,
A. susanaensis, and A. affinis. It also includes a small percentage
of bathyal marker species such as G. beccariiformis and N.
truempyi, indicating deep outer neritic to upper bathyal environ-
ments (∼150–250 m; Speijer and Schmitz, 1998).
Gavelinella beccariiformis assemblage. The Gavelinella
beccariiformis assemblage is found near the Galala Mountains
and all over Sinai. The nominative species is the most common
in almost all samples investigated. Otherwise this assemblage is
composed of N. truempyi, Osangularia plummerae, Gyroidi-
noides globosus, A. avnimelechi, various Anomalinoides (A.
affinis, A. rubiginosus), Cibicidoides (C. pseudoacutus, C. cf.
hyphalus) and numerous infrequent species. Based on upper
depth limits of ∼500 m for N. truempyi and B. trinitatensis (Van
Morkhoven et al., 1986), Speijer (1994) suggested a water depth
of 500–700 m for this assemblage. Because these taxa have been
found in low numbers in the Eastern Desert sections (see also
Speijer and Schmitz, 1998), the upper depth limits for these taxa
appear unrealistic for the Nile Basin. Consequently, the bathy-
metric range of the G. beccariiformis assemblage, occurring in
the deepest parts of the basin, is estimated somewhat shallower
(∼400–600 m).
These depth-related assemblages are fairly uniform through
time with respect to their general composition, although some
species have local lowest or highest occurrences in the Danian-
Selandian interval. Compositional variations are generally sub-
tle and in some instances appear to relate to taphonomic
processes, such as dissolution (see above) rather than to primary
differences.
Neoeponides duwi assemblage. Superimposed on the gen-
eral biotic stability in the investigated successions are a few
stratigraphic levels with a strongly deviating benthic foramini-
feral composition. In the Aweina section, the Neoeponides duwi
assemblage occurred in an ∼1 m thick interval within planktic
Danian-Selandian sea-level change and biotic excursion 283
Figure 6. Schematic spatial and temporal distribution of main benthic foraminiferal assemblages in Danian to Selandian deposits of Egypt. In-
terfingering between the Neoeponides duwi and various shallower assemblages in southern Egypt (Hewaidy, 1994) is more complex than indicated.
Bio- and chronostratigraphy as in Figure 4. PF—planktic foraminifera; CN—calcareous nannofossils; Ms—Maastrichtian; Th—Thanetian.
foraminiferal Subzone P3a and calcareous nannofossil Zone
NP4 (Speijer and Schmitz, 1998), and it includes the dark-brown
marl bed. This same unusual assemblage occurs in short inter-
vals in the Duwi, Nezzi and Qreiya sections. It generally con-
sists of abundant Neoeponides duwi, composing up to ∼60% of
the benthic assemblage, Haplophragmoides walteri, trocham-
minids and small proportions of Siphogenerinoides elegantus,
Gyroidinoides girardanus, Anomalinoides praeacutus, A. um-
boniferus, Cibicidoides pseudoacutus, Bulimina strobila and
Lenticulina spp. This assemblage is not observed in any of the
bathyal successions in the Galala area and in Sinai. In Nezzi and
Qreiya, two localities similar to Aweina, the N. duwi assemblage
is observed in the dark-brown marls and overlying shales within
Subzone P3a. In the somewhat shallower Duwi succession, the
assemblage occurs within Subzone P3a and further down in two
Danian (Subzone P1b) horizons (Table 4). Within the present
biostratigraphic constraints, the interval marked by the N. duwi
assemblage in Subzone P3a seems to be a synchronous unit in
the region.
The N. duwi assemblage is associated with highly variable
P/B ratios. The nominative species is highly abundant (relatively
and in absolute numbers) in foraminiferal assemblages with
very low P/B ratios, e.g., Gebel Qreiya sample 271185/40,
Gebel Nezzi sample 51285/20, and Aweina samples O92 + 25
and O92 + 26. Neoeponides duwi is much less abundant in ab-
solute numbers, but similarly dominant among the benthic
foraminifera in assemblages from the dark-brown beds
(271185/41, 51285/19 and O95 + 0–2) characterized by >99.5%
planktics and TOC enrichment. In the low-resolution succes-
sions of Nezzi and Qreiya, the appearance of the N. duwi as-
semblage seems to coincide with the extremely high P/B ratios.
High-resolution data of Aweina, however, show that appearance
of the N. duwi assemblage slightly predated the peak in the P/B
ratios: A sample 9–15 cm below the dark-brown bed contains a
typical N. duwi assemblage with abundant agglutinated taxa,
suggesting that the appearance of the N. duwi assemblage is not
directly linked to the conditions prevailing during deposition of
the TOC-enriched dark-brown marl beds.
In order to understand the paleoenvironmental significance
of the anomalous N. duwi assemblage, its stratigraphic and ba-
thymetric distribution needs to be considered. This type of as-
semblage has previously been found in Danian–lower Selandian
(Zones P1-P3) deposits in southern Egypt (Aswan-Uweinat
high) and central Egypt, near the Abu Tartur plateau where it is
associated with P/B ratios varying between 1 and 56% planktics
(Hewaidy, 1994; Schnack, 2000). These areas are characterized
by a carbonate-platform facies of the lower Paleocene Abu Tar-
tur platform (Schnack, 2000) and by inner to middle neritic
marls and shales (Hewaidy, 1994). Occasionally, N. duwi dom-
inates the benthic foraminiferal assemblages in these shallow ar-
eas. Haplophragmoides walteri, another frequent component of
the N. duwi assemblage, is a common constituent in inner ner-
itic and restricted marine environments in the Paleocene of
Tunisia and Texas (Kellough, 1965; Aubert and Berggren, 1976;
Kouwenhoven et al., 1997), but also occurs in Paleocene to
Eocene flysch-type deep-water deposits (Kaminski et al., 1988).
Most other taxa in this assemblage appear to have had wide ba-
thymetric distributions in Egypt, spanning from inner neritic to
upper bathyal depths (Hewaidy, 1994; Speijer, 1994; Speijer et
al., 1996; Speijer and Schmitz, 1998; Schnack, 2000). In Egypt,
the N. duwi assemblage thus seems to typify inner to middle ner-
itic (∼30–70 m) settings and the invasions into deeper shelf do-
mains, particularly those into the outer neritic realm should be
considered as anomalies.
DISCUSSION
Sea-level change during the Danian–Selandian transition
Three different sea-level scenarios for the Danian-Se-
landian transition in the region are considered. In the first two
scenarios, the interval with the N. duwi assemblage, indicative
of inner-to-middle neritic deposition, constitutes a relative sea-
level lowstand, as suggested by Speijer and Schmitz (1998). In
the third scenario it constitutes the last phase of falling sea level
and the subsequent rising sea level.
Scenario one. According to the first observations on the
benthic foraminiferal record of the Aweina section, the presence
of the N. duwi assemblage (two samples) coincided with a drop
in the percentage of planktic foraminifera from ∼90% to ∼10%
(Speijer and Schmitz, 1998). This suggested that a relative sea-
level fall and a decrease in paleodepth from ∼150–250 m to
30–70 m forced a biofacial replacement of the deeper A. avnim-
elechi assemblage by the shallower N. duwi assemblage. The re-
turn of the A. avnimelechi assemblage marked drowning of the
deeper shelf and the return to former paleodepths. The new ob-
servations indicate that this overall pattern is valid on a more
regional scale.
Scenario two. In a slightly modified interpretation, the N.
duwi assemblage is thought to have been introduced from the
shallower shelf into the deeper parts through increasing current
activity with falling sea level. The presence of the N. duwi as-
semblage on top of the channel-like surfaces supports this view.
This interpretation also differs from scenario one in that the pale-
odepth for the interval of the A. duwi assemblage cannot be accu-
rately assessed, since the assemblage would be largely constituted
by transported elements. As in scenario one, the return of the A.
avnimelechi assemblage marks the return to former paleodepths.
There are several problems with considering the interval
marked by the N. duwi assemblage as an exclusively lowstand
signal as in these two scenarios. The dark-brown marl beds con-
tain large numbers of planktic foraminifera in combination with
extremely high P/B ratios (>99.5% planktics). Such occurrences
are not compatible with a relative sea-level lowstand for the en-
tire interval characterized by the presence of the N. duwi assem-
blage. These sediments are also enriched in organic carbon and
fish remains, pointing to oxygen deficiency at the seafloor. This
cannot be reconciled with deposition under high current activity.
284 R.P. Speijer
Scenario three. The appearance of the A. umboniferus as-
semblage prior to the appearance of the N. duwi assemblage in
the Aweina record indicates 50–100 m shallowing (Speijer and
Schmitz, 1998). The subsequent replacement by the N. duwi as-
semblage, just below the dark-brown marl bed, reflects the shal-
lowest phase at the end of a falling relative sea level. In sequence
stratigraphic terminology (Posamentier et al., 1988; Van Wag-
oner et al., 1988), this could represent the late highstand systems
tract (HST) of a relative sea-level cycle (Fig. 7). The channel-like
surface may be interpreted as a type 2 sequence boundary,
marked by minor submarine erosion (Emery and Myers, 1996).
The overlying sediments, marked by rich foraminiferal assem-
blages, and at least in Duwi and Aweina common macrofossils,
seem to represent a period of condensed sedimentation during the
subsequent relative sea-level rise. This interval could represent
the transgressive systems tract (TST) in the relative sea-level
curve. Considering the absence of sand-sized terrigenous or ob-
viously redeposited material, there are no good indications for
the presence of a lowstand systems tract or shelf-margin systems
tract between the HST and TST in the southern Eastern Desert
sections, suggesting that there may be a hiatus of unknown du-
ration associated with the bottom surface of the channel.
During the early part of the rising sea level, oxygen defi-
ciency led to restricted bottom life reflected in extremely high
P/B ratios, preservation of fish remains, dark coloration and
TOC-enrichment of the sediments. Simultaneously, surface
ecosystems were also perturbed, as indicated by the near disap-
pearance of the morozovellids and the predominance of non-
keeled praemuricate and muricate planktic genera. As sea level
rose and seafloor oxygenation improved, the N. duwi assem-
blages rapidly disappeared and the normal bathymetric biofacial
distribution (Fig. 6) was restored.
It is intriguing that N. duwi remained the dominant benthic
taxon during the short oxygen-deficiency phase. Its persistence
in this interval could suggest an opportunistic life mode, like has
been suggested for other benthic foraminiferal taxa in black
shales and sapropels (e.g., Sen Gupta and Machain-Castillo,
1993). However, most of these opportunistic taxa are character-
ized by small and thin-shelled tests, whereas N. duwi is one of
the largest species in the benthic assemblages and has a thick
and strongly decorated test (Fig. 8). Alternatively, despite their
generally good preservation, it cannot be excluded that the spec-
imens of N. duwi in the dark-brown bed represent a reworked
fraction from the immediately underlying sediments. High-res-
olution data from Aweina show that the underlying 10–20 cm of
sediment contain the N. duwi assemblage (Table 4), but sample
density of the other sections does not allow to evaluate this al-
ternative. Irrespective of the ecologic characteristics of N. duwi
with respect to oxygen deficiency, with the available data sce-
nario three provides the best explanation for the sequence of
events in the Danian-Selandian transition in eastern Egypt.
Regional sea-level record
If the changes in water depth and relative sea level as
recorded in the Eastern Desert sections are of regional or eusta-
tic significance, they must also have left a record in other parts
of the basin. In Sinai, Lüning et al. (1998) found micropaleon-
tologic and sedimentologic evidence for a sequence boundary,
correlative with the one observed in the Eastern Desert (Fig. 7),
Danian-Selandian sea-level change and biotic excursion 285
Figure 7. Schematic sedimentologic and benthic foraminiferal succession within outcrop across the Danian-Selandian
transition in an outer neritic setting (e.g., Gebel Aweina). Note that in Gebel Aweina the lowest occurrence of the N. duwi
assemblage is observed already 10–15 cm below the dark-brown foraminifera-rich marl bed. Interpreted relative sea-level
history and systems tracts compared to cycle boundaries elsewhere: (1) Sinai (Lüning et al., 1998); (2) western Europe
(Hardenbol et al., 1998); (3) “Global” (Haq et al., 1988). Grey band indicates oxygen deficiency at the base of the trans-
gressive systems tract (TST). SB?—Type 2 sequence boundary?; HST—highstand systems tract; S-L—sea-level; TOC—
total organic carbon.
reflected in a reduction in P/B ratios and biostratigraphic dis-
continuities. A sea-level fall within Subbiochron P3a and a sub-
sequent unconformity was observed in the Western Desert
(Luger, 1985; Schnack, 2000). In southern Egypt, the late Dan-
ian sea-level fall is manifested by a regressive sequence of
deltaic deposits. An erosional contact marks the transition to the
overlying transgressive sequence that correlates with the lower
part of Zone P4 (Hendriks et al., 1985; Luger, 1985). Except for
the Galala area, where there is yet no evidence for sea-level
changes within Subzone P3a (Scheibner et al., 2000), the Dan-
ian-Selandian sea-level fall and subsequent rise can be moni-
tored in various parts of the Nile Basin. Estimating the amount
of relative sea-level change awaits a detailed quantitative analy-
sis, but Speijer and Schmitz (1998) indicate that the amount of
shallowing prior to the invasion of the N. duwi assemblage is
probably on the order of 50–100 m. Water depths before and af-
ter this sea-level fluctuation were similar, so the subsequent
deepening must have been in the same order of magnitude.
Eustatic sea-level change
In order to estimate the magnitude of eustatic changes, local
subsidence must be assessed. Tectonic activity in the basin ap-
pears restricted to the late Paleocene, in particular to Zones NP5
to NP9 (Strougo, 1986; Guiraud and Bosworth, 1999; Kuss et al.,
2000; Scheibner et al., 2000) and thus seems to play no role in
the Danian-Selandian transition in Egypt. In Aweina, 45 m of
compacted sediments accumulated during the interval between
the base of the Paleocene (Biochron P1c) and the top of Biochron
NP6, corresponding to ∼4 m.y. (Speijer and Schmitz, 1998). Pa-
leodepths over this time interval remained overall unchanged,
and assuming no tectonic activity, the average subsidence (with-
out correction for compaction) was 11 m/myr. The total time in-
volved in the Danian-Selandian sea-level event in Aweina (in-
cluding hiatuses) is on the order of 1 m.y. or less. If the estimate
of 50–100 m sea-level change and the assumption of no tectonic
activity are generally correct, then the role of subsidence is neg-
286 R.P. Speijer
Figure 8. SEM photographs of Neoeponides duwi (Nakkady) from
Subzone P3a in the Eastern Desert, Egypt. 1a—spiral side of specimen
from Gebel Aweina (sample O95 + 19–24 cm); 1b—side view of spec-
imen from Gebel Duwi (sample DU95DS+39A); 1c—umbilical side of
another specimen from Gebel Duwi (sample DU95DS+39A). Scale
bars are 100 µm.
ligible and the major component in the paleodepth and relative
sea-level changes observed could be eustatic change.
The postulated type 2 sequence boundary in the Eastern
Desert sections appears to correlate (Fig. 7) with the type 1 se-
quence boundary Sel 1 (Hardenbol et al., 1998) and the se-
quence boundary between third order cycles TA1.3 and TA1.4,
for which the estimated amounts of sea-level fall and subsequent
rise are 60 m and 30 m, respectively (Haq et al., 1988). The for-
mer value is within the estimated range for Aweina, but the lat-
ter value is only one half to one third of the estimate. This indi-
cates that there is fair agreement in timing and magnitude of the
Danian-Selandian sea-level fluctuation in the studied basin and
globally. The magnitude of sea-level change (∼50 m) suggests
that glacio-eustatic processes may have been involved. Although
the early Paleocene was a relatively cool period compared to the
Late Cretaceous and late Paleocene (Oberhänsli and Hsü, 1986;
Frakes et al., 1992; Zachos et al., 2001), independent evidence
for the existence of ice sheets during the early to late Paleocene
merely consists of a few records of early to “middle” Paleocene
dropstones (Dalland, 1976; Leckie et al., 1995). Oxygen iso-
topic data, however, have been interpreted as indicating that the
early Paleogene world was essentially free of ice-sheets (e.g.,
Zachos et al., 2001). A fairly good fit between eustatic cycles
and the ice-volume record reconstructed from oxygen isotopic
data currently only exists for middle Eocene and younger
records (Miller et al., 1996; Abreu and Anderson, 1998). For
now it remains enigmatic how this and other Paleocene large
magnitude sea-level fluctuations (Haq et al., 1988) may have
been eustatically controlled without good evidence for the wax-
ing and waning of large ice-sheets.
Comparison with Paleocene-Eocene Thermal
Maximum record in Egypt
In addition to indications for glacial periods within the
early to early late Paleocene (Dalland, 1976; Leckie et al.,
1995), it has been suggested that the first of a series of hyper-
thermals, short periods of extreme atmospheric and oceanic
warmth, may have occurred at this time. Negative peaks in the
deep-sea oxygen isotopic record suggest a total of perhaps six
hyperthermals during the late Paleocene to early Eocene, of
which the most prominent one was the Paleocene-Eocene Ther-
mal Maximum (Thomas et al., 2000). Another hyperthermal
may have occurred at 60.5 Ma (Thomas and Zachos, 2000), co-
inciding with a short-term polar-wards expansion of the distri-
bution of the warm-water dinoflagellate genus Apectodinium
(Bujak and Brinkhuis, 1998), at about the same time as the Dan-
ian-Selandian sea-level event. Whether or not these events truly
correlate remains to be proven, but the Paleocene-Eocene
Thermal Maximum appears to coincide with eustatic sea-level
fluctuations (Crouch, 2001; Speijer and Morsi, 2002; Speijer
and Wagner, 2002, and references therein) like the Danian-Se-
landian transition. The biotic and abiotic events at the Danian-
Selandian transition thus warrant a comparison with those of
the Paleocene-Eocene Thermal Maximum as observed in the
Nile Basin.
The Paleocene-Eocene Thermal Maximum (∼55.5 Ma) rep-
resents a brief period of global warming, particularly at high lat-
itudes, associated with an ∼3‰ negative carbon isotopic excur-
sion (Zachos et al., 1993) that was likely related to massive
methane release from continental margin sediments (e.g., Ken-
nett and Stott, 1991; Dickens et al., 1995; Katz et al., 1999; Nor-
ris and Röhl, 1999). These climatic and oceanographic changes
triggered major biotic extinctions and evolutionary innovations,
particularly among deep-sea benthic foraminifera (e.g., Tjalsma
and Lohmann, 1983; Thomas, 1998), marine micro- and nanno-
plankton (e.g., Kelly et al., 1996; Aubry, 1998; Crouch et al.,
2001), and terrestrial mammals (e.g., Gingerich, 2000). In the
Nile Basin, many of these were identified, including the carbon
isotopic excursion, anomalous planktic foraminiferal assem-
blages characterized by numerous Acarinina, and a turnover in
benthic foraminiferal assemblages (Speijer, 1994; Schmitz et
al., 1996; Speijer et al., 1996, 2000; Charisi and Schmitz, 1998;
Bolle et al., 2000; Speijer and Wagner, 2002). Some of the local
paleoenvironmental changes were related to changes in sea level
(Speijer and Morsi, 2002; Speijer and Wagner, 2002).
Several aspects of the Paleocene-Eocene Thermal Maxi-
mum in the Nile Basin are of particular interest in the compari-
son with the Danian-Selandian transition events (Table 5). Both
events are marked by the onset of oxygen deficiency on the
seafloor. During the Paleocene-Eocene Thermal Maximum, this
occurred virtually basin-wide (middle neritic to bathyal),
whereas during the Danian-Selandian transition apparently only
the middle-outer neritic realms were affected. Both events are
characterized by anomalous planktic foraminiferal assem-
blages. Although oxygen deficiency perturbed the seafloor
biota, the otherwise common keeled Morozovella virtually dis-
appeared from the surface waters and nonkeeled muricate and
praemuricate taxa (Praemurica, Acarinina) became very abun-
dant. This indicates transient environmental anomalies perturb-
ing the ecosystems of the entire water column. Sedimentologic
features of both events (minor submarine erosion, sediment
starvation, omission surfaces) may have resulted from sudden
sea-level rise—associated with circulation changes—after a
sea-level fall. Speijer and Morsi (2002) correlated the Paleo-
cene-Eocene Thermal Maximum with the transgressive systems
tract (TST) of third order sea-level cycle TA2.3 of Haq et al.
(1988). The Danian-Selandian transgressive phase appears to
correlate with transgressive deposits of the Selandian transgres-
sion of cycle TA1.4.
Many details concerning the actual existence of a Danian-
Selandian hyperthermal, correlations between the open ocean
and the Nile Basin, the sequence-stratigraphic and oxygen-iso-
topic records, and ecologic changes still need to be clarified.
This time interval has as yet received very little attention com-
pared with the Paleocene-Eocene Thermal Maximum. Never-
theless, the many similarities in sedimentologic features and
biotic patterns in the Nile Basin during these two time intervals
Danian-Selandian sea-level change and biotic excursion 287
TABLE 5. BIOTIC AND SEDIMENTARY FEATURES OF DANIAN-SELANDIAN EVENT, PALEOCENE-EOCENE THERMAL
MAXIMUM, AND BACKGROUND CHARACTERISTICS
Parameter Paleocene background Danian-Selandian transition* PETM
†
Predominant lithology Grey to pale-brown marl Dark-brown marl Dark-brown marl
Discontinuities Some paraconformities Unconformity Some distinct
Systems tract Various Transgressive Transgressive
Fish remains Rare Abundant Abundant
Peloids Rare Rare Abundant
Macrofossils Rare Common Rare
TOC <0.3% 0.8–2.0% 1.5–2.7%
Foraminifera:
% Planktics (>125 ìm) 70–95% P
§
2–99.8% P ~99% P
Morozovella
#
Common to abundant Rare Rare
Praemurica
and
Acarinina
Common to abundant Dominant Dominant
Benthic assemblage Diverse** Oligotaxic Oligotaxic
Dominant benthic taxon Depth dependent
Neoeponides duwi Anomalinoides aegyptiacus
Paleobathymetry Middle neritic to bathyal Not applicable
††
Not applicable
††
Oxygenation seafloor Good to moderate Poor Poor (variable?)
Note:
These features may not necessarily be present in every section studied. Paleocene-Eocene thermal maximum (PETM) characteristics from
Speijer and Wagner (2002).
*Compilation of observations on sections Gebel Aweina, Gebel Duwi, Gebel Nezzi, Gebel Qreiya.
†
Compilation of observations on the previous 4 sections plus Wadi Nukhl, and Ben Gurion (Israel).
§
Lower percentages planktics (<50%) where dissolution has strongly affected the assemblages.
#
Morozovella
first appears in Danian Zone P2.
**Diversity increases with paleodepth.
††
Paleobathymetric estimates based on benthic foraminifera are not reliable because of ecologic disturbance.
are significant, and suggest that at least in this basin similar
processes have taken place. It is an intriguing consideration that
the Danian-Selandian transition event may have been a precur-
sor of the Paleocene-Eocene Thermal Maximum.
CONCLUSIONS
In Egypt, a marked relative sea-level fluctuation occurred
during the Danian-Selandian transition at ∼60.5 Ma. A local se-
quence boundary appears to correlate with sequence boundaries
observed on other continental margins, suggesting eustatic con-
trol. In middle to outer neritic deposits in the Eastern Desert, the
sea-level fluctuation is associated with an incursion of the anom-
alous Neoeponides duwi benthic foraminiferal assemblage,
which is usually restricted to Danian-Selandian inner to middle
shelf regions. During the early transgressive phase, dysoxic wa-
ters spread at middle to outer neritic depths. The patterns of en-
vironmental and biotic change associated with the Danian-Se-
landian transition in the Nile Basin show strong similarities with
the ones associated with the Paleocene-Eocene Thermal Maxi-
mum in the same basin. The question arises whether the ob-
served patterns may be linked to a hyperthermal during the Dan-
ian-Selandian as postulated on the basis of preliminary oxygen
isotopic studies.
ACKNOWLEDGMENTS
Financial support was provided through the Deutsche Forsch-
ungsgemeinschaft (Sp-612/1 and 612/2). I am grateful to Chris-
tian Müller and Tom Wagner and for TOC measurements, to
Peter Luger for providing samples and stratigraphic logs of the
Qreiya and Nezzi sections and to Birger Schmitz for enabling to
analyze samples from Aweina and Duwi. Thierry Adatte, Richard
Fluegeman, Miriam Katz, Tanja Kouwenhoven, Christian
Scheibner, Ellen Thomas, and an anonymous reviewer are
thanked for constructive criticism and improvements of the text.
APPENDIX 1
Systematic part
Speijer (1994) provides taxonomic concepts and synonymies of
most benthic foraminiferal taxa mentioned in the main text. A
few notes on Neoeponides duwi are presented here. An exten-
sive taxonomic discussion is presented.
Neoeponides duwi (Nakkady)
(Fig. 8)
Synonymy
Discorbis pseudoscopos var. duwi—NAKKADY 1950, p. 689,
Plate 90, Figures 5–7.
Discorbis pseudoscopos duwi Nakkady—ANAN and SHARABI
1988, Plate 2, Figure 15.
Discorbis duwi Nakkady—HEWAIDY 1994, Figure 13, nos. 7,
9 (not no. 8) (without description).
Discorbis duwiensis Nakkady—SCHNACK 2000, p. 49 of ap-
pendix, Plate 7, Figures 15, 16.
Neoeponides duwi lacks the characteristic apertural open-
ings extending along the umbilical flaps in Discorbis and better
fits with the generic concept of Neoeponides as defined by Reiss
(1960). Note that Loeblich and Tappan (1987) provide a differ-
ent view on the generic characters of Neoeponides (Hottinger et
al., 1990).
Nakkady (1950) named Discorbis pseudoscopos var. duwi
after the locality of Gebel Duwi. Following the general practice
of naming species after localities by ending with “-ensis,”
Schnack (2000) proposed to change the name Discorbis duwi
to Discorbis duwiensis. However, the International Code of
Zoological Nomenclature (Chapter 7, Article 32) does not
allow such a change (International Commission on Zoological
Nomenclature, 1999).
REFERENCES CITED
Abreu, V.S., and Anderson, J.B., 1998, Glacial eustasy during the Cenozoic: Se-
quence stratigraphic implications: AAPG (American Association of Petro-
leum Geologists) Bulletin, v. 82, p. 1385–1400.
Anan, H.S., 1992, Maastrichtian to Ypresian stratigraphy of Abu Zenima sec-
tion, west-central Sinai, Egypt: Middle East Research Center Ain Shams
University, Earth Science Series, v. 6, p. 62–68.
Anan, H.S., and Sharabi, S.A., 1988, Benthonic foraminifera from the Upper
Cretaceous–lower Tertiary rocks of the northwest Kharga Oasis, Egypt:
Middle East Research Center Ain Shams University, Earth Science Series,
v. 2, p. 191–218.
Aubert, J., and Berggren, W.A., 1976, Paleocene benthic foraminiferal bio-
stratigraphy and paleoecology of Tunisia: Bulletin de Centre de Recherche
Pau-SNPA, v. 10, p. 379–469.
Aubry, M.-P., 1998, Early Paleogene calcareous nannoplankton evolution: A tale
of climatic amelioration, in Aubry, M.-P., et al., eds., Late Paleocene–early
Eocene climatic and biotic events in the marine and terrestrial records: New
York, Columbia University Press, p. 158–203.
Berggren, W.A., 1994, In defense of the Selandian: GFF, v. 116, p. 44–46.
Berggren, W.A., Kent, D.V., Swisher, C.C., III, and Aubry, M.-P., 1995, A re-
vised Cenozoic geochronology and chronostratigraphy, in Berggren, W.A.,
et al., eds., Geochronology, time scales, and global stratigraphic correla-
tion: SEPM (Society for Sedimentary Geology) Special Publication 54,
p. 129–212.
Berggren, W.A., Aubry, M.-P., Van Fossen, M., Kent, D.V., Norris, R.D., and
Quillévéré, F., 2000, Integrated Paleocene calcareous plankton magneto-
biochronology and stable isotope stratigraphy, DSDP Site 384 (northwest
Atlantic Ocean): Palaeogeography, Palaeoclimatology, Palaeoecology,
v. 159, p. 1–51.
Bignot, G., Curry, D., and Pomerol, C., 1997, The resistible rise of the Selandian:
Neues Jahrbuch für Geologie und Paläontologie, Monatshefte, v. 1997,
p. 114–128.
Blow, W.H., 1979, The Cainozoic Globigerinida: A study of the morphology,
taxonomy, evolutionary relationships, and the stratigraphical distribution
of some Globigerinida (mainly Globigerinacea): Leiden, Netherlands, E.J.
Brill, v. 1–3, 1413 p.
288 R.P. Speijer
short
Bolle, M.P., Tantawy, A.A., Pardo, A., Adatte, T., Burns, S., and Kassab, A.,
2000, Climatic and environmental changes documented in the upper Paleo-
cene to lower Eocene of Egypt: Eclogae Geologicae Helvetiae, v. 93,
p. 33–51.
Bujak, J.P., and Brinkhuis, H., 1998, Global warming and dinocyst changes
across the Paleocene–Eocene Epoch boundary, inAubry, M.-P., et al., eds.,
Late Paleocene–early Eocene climatic and biotic events in the marine and
terrestrial records: New York, Columbia University Press, p. 277–295.
Charisi, S.D., and Schmitz, B., 1995, Stable (δ
13
C, δ
18
O) and strontium
(
87
Sr/
86
Sr) isotopes through the Paleocene at Gebel Aweina, eastern
Tethyan region: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 116,
p. 103–129.
Charisi, S.D., and Schmitz, B., 1998, Paleocene to early Eocene paleoceanog-
raphy of the Middle East: The δ
13
C and δ
18
O isotopes from foraminiferal
calcite: Paleoceanography, v. 13, p. 106–118.
Crouch, E.M., 2001, Environmental change at the time of the Paleocene-Eocene
biotic turnover [Doctoral Thesis]: Utrecht, Netherlands, Utrecht Univer-
sity, Laboratory of Palaeobotany and Palynology Contributions Series,
v. 14, 216 p.
Crouch, E.M., Heilmann-Clausen, C., Brinkhuis, H., Morgans, H.E.G., Rogers,
K.M., Egger, H., and Schmitz, B., 2001, Global dinoflagellate event asso-
ciated with the late Paleocene thermal maximum: Geology, v. 29, p. 315–
318.
Dalland, A., 1976, Erratic clasts in the lower Tertiary deposits of Svalbard: Ev-
idence of transport by winter ice: Årbok, Norsk Polarinstitutt, v. 1976,
p. 151–165.
Dickens, G.R., O’Neil, J.R., Rea, D.K., and Owen, R.M., 1995, Dissociation of
oceanic methane hydrate as a cause of the carbon isotope excursion at the
end of the Paleocene: Paleoceanography, v. 10, p. 965–971.
Emery, D., and Myers, K., 1996, Sequence stratigraphy: London, Blackwell Sci-
ence, 297 p.
Faris, M., 1984, Biostratigraphy of the Upper Cretaceous–lower Tertiary suc-
cession of Duwi Range, Quseir District, Egypt: Revue de Micropaléon-
tologie, v. 27, p. 107–112.
Frakes, L.A., Francis, J.E., and Syktus, J.I., 1992, Climate modes of the
Phanerozoic: The history of the Earth’s climate over the past 600 million
years: Cambridge, UK, Cambridge University Press, 274 p.
Gingerich, P.D., 2000, Paleocene/Eocene boundary and continental vertebrate
faunas of Europe and North America: GFF, v. 122, p. 57–59.
Guiraud, R., and Bosworth, W., 1999, Phanerozoic geodynamic evolution of
northeastern Africa and the northwestern Arabian Platform: Tectono-
physics, v. 315, p. 73–108.
Håkansson, E., Bromley, R., and Perch-Nielsen, K., 1974, Maastrichtian chalk
of northwest Europe: A pelagic shelf sediment, in Hsü, K.J., and Jenkyns,
H.C., eds., Pelagic sediments: On land and under the sea: Special Publica-
tion of the International Association of Sedimentologists: Oxford, Black-
well, p. 211–233.
Haq, B.U., Hardenbol, J., and Vail, P., 1988, Mesozoic and Cenozoic chronos-
tratigraphy and cycles of sea-level change, in Wilgus, C.K., et al., eds., Sea-
level changes: An integrated approach: Society of Economic Paleontolo-
gists and Mineralogists Special Publication 42, p. 71–108.
Hardenbol, J., 1994, Sequence stratigraphic calibration of Paleocene and lower
Eocene continental margin deposits in northwest Europe and the U.S. Gulf
Coast with the oceanic chronostratigraphic record: GFF, v. 116, p. 49–51.
Hardenbol, J., Thierry, J., Farley, M.B., De Graciansky, P.-C., and Vail, P.R.,
1998, Mesozoic and Cenozoic sequence chronostratigraphic framework of
European basins, in De Graciansky, P.-C., et al., eds., Mesozoic and Ceno-
zoic sequence stratigraphy of European basins: SEPM (Society for Sedi-
mentary Geology) Special Publication 60, p. 3–13.
Hendriks, F., Luger, P., Kallenbach, H., and Schroeder, J.H., 1985, Faziesmuster
und Stratigraphie der campanen bis paleozänen Schichtenfolgen im
südlichen Obernil-Becken (Western Desert, Ägypten): Zeitschrift der
Deutschen Geologischen Gesellschaft, v. 136, p. 207–233.
Hendriks, F., Luger, P., Bowitz, J., and Kallenbach, H., 1987, Evolution of de-
positional environments of southeast Egypt during the Cretaceous and
lower Tertiary: Berliner Geowissenschaftliche Abhandlungen, Reihe A,
Geologie und Paläontologie, v. 75, p. 49–82.
Hewaidy, A.G.A., 1994, Biostratigraphy and paleobathymetry of the Garra-
Kurkur area, southwest Aswan, Egypt: Middle East Research Center Ain
Shams University, Earth Science Series, v. 8, p. 48–73.
Hottinger, L., Reiss, Z., and Halicz, E., 1990, Comments on Neoeponides
(foraminifera): Revue de Paléobiologie, v. 9, p. 335–340.
International Commission on Zoological Nomenclature, 1999, International
code of zoological nomenclature (4th edition): London, The International
Trust for Zoological Nomenclature, 306 p.
Kaminski, M.A., Gradstein, F.M., Berggren, W.A., Geroch, S., and Beckmann,
J.P., 1988, Flysch-type agglutinated foraminiferal assemblages from
Trinidad: Taxonomy, stratigraphy, and paleobathymetry: Abhandlungen
der Geologischen Bundesanstalt, v. 41, p. 155–227.
Katz, M.E., Pak, D.K., Dickens, G.R., and Miller, K.G., 1999, The source and
fate of massive carbon input during the latest Paleocene thermal maximum:
Science, v. 286, p. 1531–1533.
Kellough, G.R., 1965, Paleoecology of the Foraminiferida of the Wills Point
Formation (Midway Group) in northeast Texas: Transactions of the Gulf
Coast Association of Geological Societies, v. 15, p. 73–153.
Kelly, D.C., Bralower, T.J., Zachos, J.C., Premoli Silva, I., and Thomas, E.,
1996, Rapid diversification of planktonic foraminifera in the tropical
Pacific (ODP Site 865) during the late Paleocene thermal maximum:
Geology, v. 24, p. 423–426.
Kennett, J.P., and Stott, L.D., 1991, Abrupt deep-sea warming, palaeoceano-
graphic changes, and benthic extinctions at the end of the Paleocene:
Nature, v. 353, p. 225–229.
Kouwenhoven, T.J., Speijer, R.P., van Oosterhout, C.W.M., and van der Zwaan,
G.J., 1997, Benthic foraminiferal assemblages between two major extinc-
tion events: The Paleocene El Kef section, Tunisia: Marine Micropaleon-
tology, v. 29, p. 105–127.
Kuss, J., Scheibner, C., and Gietl, R., 2000, Carbonate to platform transition
along an Upper Cretaceous to lower Tertiary Syrian Arc uplift, Galala
Plateaus, Eastern Desert of Egypt: GeoArabia, v. 5, p. 405–424.
Leckie, D.A., Morgans, H., Wilson, G.J., and Edwards, A.R., 1995, Mid-
Paleocene dropstones in the Whangai Formation, New Zealand: Evidence
of mid-Paleocene cold climate?: Sedimentary Geology, v. 97, p. 119–129.
Loeblich, A.R.J., and Tappan, H., 1987, Foraminiferal genera and their classifi-
cation: New York, Van Nostrand Reinhold, 970 p.
Luger, P., 1985, Stratigraphie der marinen Oberkreide und des Alttertiärs im süd-
westlichen Obernil-Becken (southwest- Ägypten) unter besonderer
Berücksichtigung der Mikropaläontologie, Palökologie und Paläogeogra-
phie: Berliner Geowissenschaftliche Abhandlungen, Reihe A, Geologie
und Paläontologie, v. 63, 151 p.
Luger, P., 1988, Maestrichtian to Paleocene facies evolution and Cretaceous–
Tertiary boundary in middle and southern Egypt: Revista Espanola de
Paleontologia, Numero extraordinario, p. 83–90.
Lüning, S., 1997, Late Cretaceous–early Tertiary sequence stratigraphy, pale-
oecology and geodynamics of eastern Sinai, Egypt [Ph.D. thesis]: Bremen
University, Berichte aus dem Fachbereich Geowissenschaften der Univer-
sität Bremen, Nr. 98, 218 p.
Lüning, S., Marzouk, A.M., and Kuss, J., 1998, The Paleocene of central East
Sinai, Egypt: “Sequence stratigraphy” in monotonous hemipelagites: Jour-
nal of Foraminiferal Research, v. 28, p. 19–39.
Mart, Y., 1991, Some Cretaceous and early Tertiary structures along the distal
continental margin of the southeastern Mediterranean: Israel Journal of
Earth Sciences, v. 40, p. 77–90.
Miller, K.G., Mountain, G.S., the Leg 150 Shipboard Party, and Members of the
New Jersey Coastal Plain Drilling Project, 1996, Drilling and dating New
Jersey Oligocene–Miocene sequences: Ice volumes, global sea level, and
Exxon records: Science, v. 271, p. 1092–1095.
Danian-Selandian sea-level change and biotic excursion 289
short
Nakkady, S.E., 1950, A new foraminiferal fauna from the Esna shales and Up-
per Cretaceous chalk of Egypt: Journal of Paleontology, v. 24, p. 675–692.
Norris, R.D., and Röhl, U., 1999, Carbon cycling and chronology of climate
warming during the Paleocene–Eocene transition: Nature, v. 401, p. 775–
778.
Oberhänsli, H., and Hsü, K.J., 1986, Paleocene–Eocene paleoceanography, in
Hsü, K.J., ed., Mesozoic and Cenozoic oceans: Geodynamics Series 15,
p. 85–100.
Olsson, R.K., Hemleben, C., Berggren, W.A., and Huber, B.T., 1999, Atlas of
Paleocene planktonic foraminifera: Smithsonian Contributions to Paleo-
biology, v. 85, 252 p.
Posamentier, H.W., Jervey, M.T., and Vail, P.R., 1988, Eustatic controls on clas-
tic deposition, I: Conceptual framework, in Wilgus, et al., eds., Sea-level
changes: An integrated approach: Society of Economic Paleontologists and
Mineralogists Special Publication 42, p. 109–124.
Reiss, Z., 1960, Structure of so-called Eponides and some other rotaliiform
foraminifera: Israel Geological Survey, Bulletin, v. 29, p. 1–19.
Said, R., 1962, The geology of Egypt: Amsterdam, Elsevier, 377 p.
Said, R., 1990, Cenozoic, in Said, R., ed., The geology of Egypt: Rotterdam,
A.A. Balkema, p. 451–486.
Scheibner, C., 2001, Architecture of a carbonate platform-to-basin transition on
a structural high (Campanian–early Eocene, Eastern Desert, Egypt): Clas-
sical and modeling approaches combined [Ph.D. thesis]: Bremen Univer-
sity, Bremen, Berichte aus dem Fachbereich Geowissenschaften der Uni-
versität Bremen, Nr. 186, 174 p.
Scheibner, C., Kuss, J., and Marzouk, A.M., 2000, Slope sediments of a Paleo-
cene ramp-to-basin transition in northeast Egypt: International Journal of
Earth Sciences, v. 88, p. 708–724.
Scheibner, C., Marzouk, A.M., and Kuss, J., 2001, Maastrichtian–early Eocene
litho-biostratigraphy and palaeogeography of the northern Gulf of Suez
region, Egypt: Journal of African Earth Sciences, v. 32, p. 223–255.
Schmitz, B., Speijer, R.P., and Aubry, M.-P., 1996, Latest Paleocene benthic ex-
tinction event on the southern Tethyan shelf (Egypt): Foraminiferal stable
isotopic (δ
13
C, δ
18
O) records: Geology, v. 24, p. 347–350.
Schmitz, B., Molina, E., and Von Salis, K., 1998, The Zumaya section in Spain:
A possible global stratotype section for the Selandian and Thanetian
Stages: Newsletters on Stratigraphy, v. 36, p. 35–42.
Schnack, K., 2000, Biostratigraphie und fazielle Entwicklung in der Oberkreide
und im Alttertiär im Bereich der Kharga Schwelle, Westliche Wüste, south-
west Ägypten [Ph.D. thesis]: Bremen University, Bremen, Berichte, Fach-
bereich Geowissenschaften, Universität Bremen, Nr. 151, 142 p.
Sen Gupta, B.K., and Machain-Castillo, M.L., 1993, Benthic foraminifera in
oxygen-poor habitats: Marine Micropaleontology, v. 20, p. 183–201.
Shahar, J., 1994, The Syrian arc system: An overview: Palaeogeography, Palaeo-
climatology, Palaeoecology, v. 112, p. 125–142.
Speijer, R.P., 1994, Extinction and recovery patterns in benthic foraminiferal
paleocommunities across the Cretaceous–Paleogene and Paleocene–
Eocene boundaries [Ph.D. thesis]: Geologica Ultraiectina, v. 124, p. 191 p.
Speijer, R.P., and Morsi, A.M., 2002, Ostracode turnover and sea-level changes
associated with the Paleocene-Eocene thermal maximum: Geology, v. 30,
p. 23–26.
Speijer, R.P., and Schmitz, B., 1998, A benthic foraminiferal record of Paleocene
sea level and trophic/redox conditions at Gebel Aweina, Egypt: Palaeo-
geography, Palaeoclimatology, Palaeoecology, v. 137, p. 79–101.
Speijer, R.P., and Wagner, T., 2002, Sea-level changes and black shales associ-
ated with the late Paleocene thermal maximum: Organic-geochemical and
micropaleontologic evidence from the southern Tethyan margin (Egypt-
Israel), in Koeberl, C., and MacLeod, K.G., eds., Catastrophic events and
mass extinctions: Impacts and beyond: Boulder, Colorado, Geological
Society of America Special Paper 356, p. 533–549.
Speijer, R.P., Van der Zwaan, G.J., and Schmitz, B., 1996, The impact of Pale-
ocene–Eocene boundary events on middle neritic benthic foraminiferal as-
semblages from Egypt: Marine Micropaleontology, v. 28, p. 99–132.
Speijer, R.P., Schmitz, B., and Luger, P., 2000, Stratigraphy of late Paleocene
events in the Middle East: Implications for low- to middle-latitude succes-
sions and correlations: Journal of the Geological Society of London, v. 157,
p. 37–47.
Stouge, S., Ferre, H.B., Rasmussen, J.A., Roncaglia, L., and Sheldon, E., 2000,
Micro- and nannofossil biostratigraphy across the Danian-Selandian (Pa-
leocene) stage boundary at Gemmas Allé, Copenhagen, Denmark: GFF,
v. 122, p. 161–162.
Strougo, A., 1986, The Velascoensis event: A significant episode of tectonic ac-
tivity in the Egyptian Paleogene: Neues Jahrbuch für Geologie und Paläon-
tologie, Abhandlungen, v. 173, p. 253–269.
Tawadros, E.E., 2001, Geology of Egypt and Libya: Rotterdam, A.A. Balkema,
468 p.
Thomas, E., 1998, Biogeography of the late Paleocene benthic foraminiferal ex-
tinction, in Aubry, M.-P., et al., eds., Late Paleocene–early Eocene climatic
and biotic events in the marine and terrestrial records: New York, Colum-
bia University Press, p. 214–243.
Thomas, E., and Zachos, J.C., 2000, Was the late Paleocene thermal maximum
a unique event?: GFF, v. 122, p. 169–170.
Thomas, E., Zachos, J.C., and Bralower, T.J., 2000, Deep-sea environments on
a warm Earth: Latest Paleocene–early Eocene, in Huber, B.T., et al., eds.,
Warm climates in Earth history: Cambridge, UK, Cambridge University
Press, p. 132–160.
Thomsen, E., 1994, Calcareous nannofossil stratigraphy across the Danian-
Selandian boundary in Denmark: GFF, v. 116, p. 65–67.
Thomsen, E., and Heilmann-Clausen, C., 1985, The Danian-Selandian bound-
ary at Svejstrup with remarks on the biostratigraphy of the boundary in
western Denmark: Bulletin of the Geological Society of Denmark, v. 33,
p. 341–632.
Tjalsma, R.C., and Lohmann, G.P., 1983, Paleocene–Eocene bathyal and abyssal
benthic foraminifera from the Atlantic Ocean: Micropaleontology, Special
Publication, v. 4, 90 p.
Toumarkine, M., and Luterbacher, H., 1985, Paleocene and Eocene planktic
foraminifera, in Bolli, H.M., et al., eds., Plankton stratigraphy: Cambridge,
UK, Cambridge University Press, p. 87–154.
Van Morkhoven, F.P.C.M., Berggren, W.A., and Edwards, A.S., 1986, Cenozoic
cosmopolitan deep-water benthic foraminifera: Bulletin des Centres de
Rechèrches Exploration-Production Elf-Aquitaine, Memoir 11, 421 p.
Van Wagoner, J.C., Posamentier, H.W., Mitchum, R.M., Jr., Vail, P.R., Sarg, J.F.,
Loutit, T.S., and Hardenbol, J., 1988, An overview of the fundamentals of
sequence stratigraphy and key definitions, in Wilgus, C.K., et al., eds., Sea-
level changes: An integrated approach: Society of Economic Paleontolo-
gists and Mineralogists Special Publication 42, p. 39–45.
Zachos, J.C., Lohmann, K.C., Walker, J.C.G., and Wise, S.W., 1993, Abrupt cli-
mate changes and transient climates during the Paleogene: A marine per-
spective: Journal of Geology, v. 101, p. 191–213.
Zachos, J., Pagani, M., Sloan, L., Thomas, E., and Billups, K., 2001, Trends,
rhythms, and aberrations in global climate 65 Ma to present: Science,
v. 292, p. 686–693.
M
ANUSCRIPT
A
CCEPTED BY THE
S
OCIETY
A
UGUST
13, 2002
290 R.P. Speijer
Printed in the USA
