FORMAL EARLY NEOLITHIC FLINT TOOLKITS ...

Fig. 4. Cryptocrystalline chalcedony, microfauna filled with microcrystalline
chalcedony and clastic particles – blade fragment, Neolithic
archaeological site Yabalkovo, sample N18; possible source – Upper
Cretaceous (Moesian flint); transmitted light, crossed polars
Further thin section analyses should reduce the potential
candidates for original outcrops of the toolkits under
discussion. Although archaeological evidence for Neolithic
workshops in the region of North-East Bulgaria is absent, we
have to presume that they existed in the Early Neolithic for
ensuring suitable nodules, cores (about 18-20 cm long) and
debitage (blades): all these products were predestined for long
distance exchange of good and perhaps embodied know-how.
Sedimentological aspects of prehistoric flints
The siliceous concretions (flint) are relatively well studied in
Bulgaria. The published sedimentological works are about
Upper Jurassic siliceous concretions in West Bulgaria
(Atanasov, 1954; Nachev, 2005), Low Cretaceous flint in
Northeast Bulgaria (Goranov, 1965; Nachev, Kanchev, 1984;
Nachev, 2008, in press) and Upper Cretaceous siliceous
concretions (Soultanov, 1982; Nachev, 2008 in press).
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Part of the present work is based on sedimentological
examinations of flint and flint-like materials from the territory of
Bulgaria. They include terrain observation (more than 100
localities), macroscopic observations (descriptions of
specimens – 480 numbers) and microscopic descriptions (700
thin-sections from 65 outcrops). The microscopic observations
of artefacts with Neolithic and Chalcolithic age have
preliminary character and are based on macro-and
microscopic observations of 180 thin sections from 16
archeological sites. According to some authors, the siliceous
concretions (flint) consist from autogenic minerals of SiO2
(silica). They have concretion structure and are hosted
predominantly in limestones or chalk. The natural flint outcrops
are widely spread in Bulgaria. The siliceous concretions are
represented in almost geographic and morphotectonic zones.
Significant accumulations are located in the Moesian
Platform and adjustment parts of the Balkan Alpine Orogen
(Fig. 5) (Nachev, Nachev, 1986). In the Phanerozoic rocks in
Bulgaria the siliceous concretions are found in 16 stratigraphic
levels and different paleogeodynamic environments are
recognized (Nachev, Nachev, 1989). The main stratigraphic
levels, which are of theoretical and practical interest for
archeology, are the Upper Jurassic (Oxfordian), the Low
Cretaceous (Aptian) and the Upper Cretaceous (Coniacian,
Campanian and Maastrichtian).Some meaning in archaeology
may have the hydrothermal chalcedony veins in the Upper
Cretaceous Sredna Gora zone (Sredna Gora atypical flint) and
in the Oligocene Rhodopes volcanic zone (Rhodopes atypical
flint). The term “Pre-Balkan Platform” is not a correct term for
Moesian Platform. The “Balkan flint” probably means every flint
in the Moesian Platform and adjustment parts of the Balkan
Alpine Orogen including both Low Cretaceous (Aptian) flint and
Upper Cretaceous (Campanian and Maastrichtian) flint. The
geographic and stratigraphic distribution of the main levels of
siliceous concretions (flint) with archaelogocal significance in
Bulgaria is shown on Fig. 5.
Fig. 5. Geological map of the main types of flint-born rocks in Bulgaria: 1 – Upper Jurassic limestones (Oxfordian age) with siliceous concretions (J3 ox ) -
Hemus flint; 2 – Low Cretaceous (Aptian age) limestones with siliceous concretions (К1 a ) – Luda Gora flint (Dobrudzha flint); 3 – Upper Cretaceous chalk
and chalk-like limestones (Campanian and Maastrictian ages) with siliceous concretions (К2 cp-m ) – Moesia flint; 4 – Upper Cretaceous volcanogenous
rocks (Coniacian, Santonian and Campanian ages) in Sredna Gora Zone (K2 Cn-Cp ) – Sredna Gora atypical flint; 5 – Chalcedony veins in Oligocene
volcanogenous rocks in Rhodope Zone (Pg3) – Rhodope atypical flint ; 6 – boundary between tectonic zones