14
The Historical Background
in the Middle Pliocene (Plaisancian) (Moshkovitz, 1963, 1968). For the end of the
Pliocene, Reiss (1968) gives a radiometric date of nearly two million years (precisely 1.85) and states that the Plio-Pleistocene boundary in the Mediterranean,
established by integrated analysis of multiple criteria, preceded the first major
glaciation in the Mediterranean area by more than a million years. The end of the
Pliocene must have been more or less contemporaneous with the establishment of
the sill connection through the recent Gibraltar Straits and the transformation of
the Paleomediterranean with its deep-sea connection into the present-day sillenc10sed Mediterranean (Benson and Sylvester-Bradley, 1971). This change set
the scene for the Pleistocene environmental fluctuations ofthis sea.
Much less is known about the Tertiary Red Sea. Nevertheless, events were
probably far more simple in this rectilinear graben dominated by the effect of the
Syro-African rift movement. In the Eocene, the Gulf of Suez was a southward
extension of the Tethyian Mediterranean, similar to the gulf which extended
further west into the future Nile valley.
There is disagreement in the evaluation of the age of the last marine Mediterranean influence in the future Red Sea basin and also on whether the Mediterranean and Indo-Pacific faunas ever came to mingle there during the Miocene
or Pliocene.
Gohar (1954) assumes that the Paleomediterranean Gulf extended along the
present-day Gulf of Suez, and further down approximately to the latitude of
Qosseir. After a temporary loss of contact during the Oligocene, the graben was
again flooded with Paleomediterranean water in the Miocene, a view accepted by
Ekman (1967). Klausewitz (1960) considers that the connection was soon interrupted and that the graben was filled in the Upper Miocene by an "immense
inland sea". This lacustrine period is accepted also by Gohar (1954). Brackish
water marls and gypsum in the graben are attributed to the Middle Miocene by
Hume (1916) and Beadnell (1924).
What happened subsequently is a matter of considerable dissent. The Red Sea
of the Pliocene was, according to Gohar (1954), connected to the Mediterranean
again but opened for the first time to the Indian Ocean, and consequently acquired a mixed fauna. This conception was taken up by Fox (1926). Klausewitz
(1960) extends this coexistence of both faunas to the Lower Pleistocene. Ekman
(1967) sets the start of the faunal intermingling at the Middle Pliocene. All these
judgments are probably based on the view that the "Ostrea-Pecten series" of
Beadnell situated by the first author in the Mio-Pliocene and by the second in the
Upper Miocene were considered remnants of a mixed fauna. Neumann (1966)
writes that sediments along the Gulf of Suez show that the northem end of the
Red Sea was open to the Mediterranean only until early Quatemary times. Cox
(1929) and especially Moshkovitz (1968) consider that this is probably untrue and
that the only marine influence after the Mid or Late Miocene inland lake was an
Indo-Pacific one. Moshkovitz also uses the data of Goldberg (1963), from the
Island of Tiran at the entrance of the Gulf of Aqaba. He states very categorically
that: "In the end of the period of gypsum denosition, the opening of the Red Sea
to the Indian Ocean occurred (probably in the Lower Pliocene) and Indo-Pacific
fauna invaded. From this time up until now there was no renewed contact between the Red Sea and the Mediterranean. All the proofs for such a contact are
more than scanty". Benson (personal communication) considers that all the
The Historical Background
in the Middle Pliocene (Plaisancian) (Moshkovitz, 1963, 1968). For the end of the
Pliocene, Reiss (1968) gives a radiometric date of nearly two million years (precisely 1.85) and states that the Plio-Pleistocene boundary in the Mediterranean,
established by integrated analysis of multiple criteria, preceded the first major
glaciation in the Mediterranean area by more than a million years. The end of the
Pliocene must have been more or less contemporaneous with the establishment of
the sill connection through the recent Gibraltar Straits and the transformation of
the Paleomediterranean with its deep-sea connection into the present-day sillenc10sed Mediterranean (Benson and Sylvester-Bradley, 1971). This change set
the scene for the Pleistocene environmental fluctuations ofthis sea.
Much less is known about the Tertiary Red Sea. Nevertheless, events were
probably far more simple in this rectilinear graben dominated by the effect of the
Syro-African rift movement. In the Eocene, the Gulf of Suez was a southward
extension of the Tethyian Mediterranean, similar to the gulf which extended
further west into the future Nile valley.
There is disagreement in the evaluation of the age of the last marine Mediterranean influence in the future Red Sea basin and also on whether the Mediterranean and Indo-Pacific faunas ever came to mingle there during the Miocene
or Pliocene.
Gohar (1954) assumes that the Paleomediterranean Gulf extended along the
present-day Gulf of Suez, and further down approximately to the latitude of
Qosseir. After a temporary loss of contact during the Oligocene, the graben was
again flooded with Paleomediterranean water in the Miocene, a view accepted by
Ekman (1967). Klausewitz (1960) considers that the connection was soon interrupted and that the graben was filled in the Upper Miocene by an "immense
inland sea". This lacustrine period is accepted also by Gohar (1954). Brackish
water marls and gypsum in the graben are attributed to the Middle Miocene by
Hume (1916) and Beadnell (1924).
What happened subsequently is a matter of considerable dissent. The Red Sea
of the Pliocene was, according to Gohar (1954), connected to the Mediterranean
again but opened for the first time to the Indian Ocean, and consequently acquired a mixed fauna. This conception was taken up by Fox (1926). Klausewitz
(1960) extends this coexistence of both faunas to the Lower Pleistocene. Ekman
(1967) sets the start of the faunal intermingling at the Middle Pliocene. All these
judgments are probably based on the view that the "Ostrea-Pecten series" of
Beadnell situated by the first author in the Mio-Pliocene and by the second in the
Upper Miocene were considered remnants of a mixed fauna. Neumann (1966)
writes that sediments along the Gulf of Suez show that the northem end of the
Red Sea was open to the Mediterranean only until early Quatemary times. Cox
(1929) and especially Moshkovitz (1968) consider that this is probably untrue and
that the only marine influence after the Mid or Late Miocene inland lake was an
Indo-Pacific one. Moshkovitz also uses the data of Goldberg (1963), from the
Island of Tiran at the entrance of the Gulf of Aqaba. He states very categorically
that: "In the end of the period of gypsum denosition, the opening of the Red Sea
to the Indian Ocean occurred (probably in the Lower Pliocene) and Indo-Pacific
fauna invaded. From this time up until now there was no renewed contact between the Red Sea and the Mediterranean. All the proofs for such a contact are
more than scanty". Benson (personal communication) considers that all the