extended abstracts - Geomorphic Processes and Geoarchaeology

Geomorphic processes and geoarchaeology
0.8 m / years. The total loss of land for the last 1.5 thousand years is estimated about 400-
500 m.
Using archival cartographic and geological materials and geological studies
conducted by the authors in 2004-2011 showed that the modern topography of the coastal
land of Kamysh-Burun Bay is a series of ancient generations of Kamysh-Burun spit,
formed during the follow-up paleo- bay on the spot of estuarine zone of Churubash
estuary. The average width of the zone of accumulation and, as a consequence,
forwarding of Kamysh-Burun Bay coastline is 2-2.5 km. According to preliminary data
this zone of the coastal marine accumulation is a fairly uniform thick layer of shell sand
with the capacity of 3.5-4.5 m. Modern Kamysh-Burun Spit represents the newest
generation of beach ridges.
The data of coring have shown that the beach-ridges plain is consist of coarse
shelly sands which have been redeposited during erosion of more old sandy body that
have been located more seaward from the present shoreline and was related with mid-
Holocene highstand. The thickness of superficial coarse layer is about 3.5-4.5 m. The
mean width of the beach-ridge plain reach the 2.0-2.5 km that define the scale of
advancing of shoreline during the last 1.5 thousand years.
Below the subsurface cover of coarse sands the extensive strata of fine well-sorted
sand with shells spreads in the inner part of the former semi-enclosed shallow embayment
that reach the eastern flank of cliffed shore that bound the coastal lowland. The set of
radiocarbon dates of shells from fine sands have shown that the shallow embayment in
the inner part of coastal lowland existed between the end of the II millennium BC up to
end of the I millennium AD. The belt of silty clay in the outer part of the former
embayment confirm the semi-enclosed type of the waterbody and existence the sandy
barrier that located easterly from present Kamysh-Burun spit and have been related with
mid-Holocene highstand of sea level. This barrier have been destroyed during the
acceleration of sea level rise during the last 1,5-1,0 thousands years. The eroded sands
have been removed in the inner part of the paleo bay and redeposited during formation of
the different generation of the beach ridges that infilled the inner part of embayment.
In general, the underwater archaeological survey indicate that the sea level during
the Phanagory regression for the maritime part of Nymphaion in the 4 th century BC could
correspond to the depth of 5.0-5.5 m below the present. Consequently, during the last
2.5 ky more than 400 m of ancient coastal strip has got under water, which is about 3
square kilometers of Nymphaion polis. This means that the majority of the most ancient
rural settlements, burial structures, as well as all port buildings of Nymphaion have been
flooded [1]. A similar situation can be observed for the coastal area of rural district of
Bosporus cities of Tyritaka, Panticapaeum and Myrmekion.
The results of the geological work in the vicinity of Tyritaka have shown that the
fragments of local pottery of Hellenistic time have been met at depth 4,5-5,5 m below
present sea level that didn’t contradict to the underwater archeological data and could be
used for sea level reconstruction [4]. The geomorphological data have permitted to
reconstruct the boundary of embayment which existed in Kamysh-Burun bay in classic
time. In the bayhead the paleoshoreline was adjacent to southern border of Tyritaka. In
the southern part of embayment she bordered the northern flank of the rocky upland on
which the antique Nymphaeum have located. This creates the geological base for
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