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sequences at the delta’s coastal margin Figure 2. (A) Geographic features and localities in the northern sector of the
(Fig. 2A) are based on stratigraphic, sedi- Nile delta, including those cited in the text. (B) Map showing average thick-
mentological, petrologic, biogenic, and ness (in m) of Holocene section (CD) in sectors I, II, and III of the northern
geochemical analyses of >3000 samples delta. (C) Lithologic aspects and physiographic features in the delta margin
selected from 85 radiocarbon-dated drill and offshore sector. Arrows highlight three major coastal shifts and rever-
cores (dots in Fig. 2B). These cores and sals through time: I, coastline landward retreat in post-glacial time (ca.
supplemental study materials were exam- 16,000 B.C.) to early Holocene (ca. 6000–5500 B.C.); II, coastline seaward
ined during the past 30 years by the advance from early Holocene (ca. 6000–5500 B.C.) to late Holocene (ca.
Smithsonian Institution’s Mediterranean 2500 B.C.); and III, coastline landward retreat, once again, from late Holo-
Basin (MEDIBA) Program (Stanley et al., cene (ca. 2500 B.C.) to present.
1996; Stanley and Warne, 1998). Total core
lengths range from 20 m to >50 m from Idku, and Maryut; Fig. 2A), are of modest surges and wave-driven coastal currents
the delta surface downward, with many depths, ranging to little more than 1 m that displace sediment mostly toward the
sections radiocarbon dated to provide a below msl. They are open to the sea, and east (Frihy et al., 2002). Coastal material is
chrono-stratigraphic framework. The their waters are brackish to saline. The preferentially eroded from seaward pro-
upper part of the Late Pleistocene’s largely delta’s coastal margin sequences of Late jecting headlands, including the two Nile
sandy sections (Mit Ghamer Fm.) is gener- Pleistocene to present age include Nile flu- distributary promontories and the bowed-
ally recovered at most core bases; these vial and desert wind-borne sediment, and out coast in the Baltim region
older sections, in turn, are covered by also those derived from eroded marine (Fig. 2A). This displaced sediment forms
Holocene nutrient-rich silty mud and fine sections from nearshore deposits. Sandy the long, narrow sand barriers at the sea-
sand sequences (Bilquas Fm.) that thicken delta beaches are in part shaped by the ward margin of coastal lagoons, while
northward and eastward along the coast Mediterranean’s semi-diurnal microtidal landward-driven masses of wind-blown
(Fig. 2B). Core sites are distributed from and surge effects, and especially by strong sand have accumulated as extensive dune
east to west in a curvilinear, coast-parallel winds that in winter are directed toward fields along the north-central delta coast
area of ~7000 km2 that forms the northern the SE. The present coastline’s arcuate east of Baltim (Figs. 2A and 2C). A large
third of the delta; most sites are positioned form results from powerful winter wave body of published work summarizes the
‫ޒ‬30 km from the present arcuate shoreline
at elevations to ~1 m or lower above msl.

Additional data are derived from other
sources: cores obtained by others in the
delta (Attia, 1954; Marriner et al., 2012);
sediment grab samples and short gravity
cores on the adjacent Nile delta shelf
(Summerhayes et al., 1978); and dated
vibro-core and seafloor data at major,
now-submerged archaeological sites of
Greek and Roman age seaward of the
delta, including major ones in Abu Qir
Bay and Alexandria’s Eastern Harbor
(Bernand and Goddio, 2002; Stanley,
2007; Robinson and Wilson, 2010). Also
useful are published analyses of satellite
surveys of delta surface and sea-level
elevations, deep subsurface stratigraphic
and structural data obtained in the north-
ern delta and offshore by means of 2D and
3D geophysical surveys, and associated
well core information. These data are com-
piled by the hydrocarbon (largely gas)
companies conducting exploration in this
region during the past half-century.

The distance between the delta’s south-
ern apex near Cairo and the coast is 160
km, and the delta length along its arcuate
coastline is ~270 km, from Alexandria in
the west to the margin south of the Gulf of
Tineh in the east. Four elongate brackish
lagoons, positioned from east to west adja-
cent to the delta coast (Manzala, Burullus,

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