6 Boreal Submerged Black Sea Landscapes
77
Conversely, marine geologists and geophysicists have produced many detailed
studies of underwater features relating to sea-level change, coastal sediment dynamics and palaeoclimate across the full depth range of potentially habitable landscapes
on the continental shelf, but rarely with archaeological goals and issues of prehistoric
social change in view. This is why for instance, the objectives of the FP5 European
project ASSEMBLAGE was to use most advanced geophysical techniques to asses
the sedimentary system of the Western Black Sea since the Last Glacial Maximum.
Modern high-technology equipment was used and ground truthing was carried out to
determine the geophysical features recognized. At present, important analyses such
as stable isotope measurements as well as AMS
14 C age determinations from core
samples at a small sampling interval are undergone.
Most important results used in this paper are coming from interpretation of data
acquired during surveys realised in the framework of two main projects; (1) BlaSON:
a French-Romanian bilateral project for which two surveys coordinated by IFREMER were carried out on board the French RV “Le Suroît” in 1998 and 2002, (2)
ASSEMBLAGE: a FP5 European project for which two surveys on board the French
RV “Le Marion Dufresne” in 2004 and the Romanian RV “Mare Nigrum” in 2005
were carried out. For all these surveys a differential GPS system was deployed for accurate (about 1 m) positioning and every vessel was equipped with swath bathymetry
systems. Very high-resolution seismic lines were shot simultaneously using a Chirp
sonar system. All data acquisition were synchronized and digitally recorded. The
navigation profiles presented here are displayed in Fig. 6.2.
Together with geophysical surveys, ground truthing was obtained from cores.
Sediment cores have been recovered using Kullenberg-type piston corers. More than
100 cores were collected among which, some reach more than 40 m long of sediment
recovery. Studies are still ongoing on the analyses of the samples.
6.3 Results
6.3.1 Morphological Information
Prior to these important Black Sea campaigns, work and publications reported presence of terraces on many Black Sea margins, from the narrow Caucasus shelves
(Ostrovskiy et al. 1977; Shimkus et al. 1980) to the Northern Turkish shelf (Algan
et al. 2002; Ballard et al. 2000). Among these terraces, shells belonging to past littoral environments were dated between 19,000 to 9,000 years BP (Chepalyga 1984;
Dimitrov 1982; Ostrovskiy et al. 1977; Scherbakov et al. 1978). On the Romanian
continental shelf, Popescu et al. (2004) and Lericolais et al. (2007b) have noticed the
absence of incised river channels below − 90 m water depth where a wave-cut terrace
like morphology was mapped about 100 km far from the Danube delta (Fig. 6.3).
Wave-cut terraces are erosion surfaces created by erosion from wave action indicating the vicinity of the shoreline. Since rivers do not always generate continuous
incised valleys all along the shelf (Lericolais et al. 2001; Talling 2000; Wescott
77
Conversely, marine geologists and geophysicists have produced many detailed
studies of underwater features relating to sea-level change, coastal sediment dynamics and palaeoclimate across the full depth range of potentially habitable landscapes
on the continental shelf, but rarely with archaeological goals and issues of prehistoric
social change in view. This is why for instance, the objectives of the FP5 European
project ASSEMBLAGE was to use most advanced geophysical techniques to asses
the sedimentary system of the Western Black Sea since the Last Glacial Maximum.
Modern high-technology equipment was used and ground truthing was carried out to
determine the geophysical features recognized. At present, important analyses such
as stable isotope measurements as well as AMS
14 C age determinations from core
samples at a small sampling interval are undergone.
Most important results used in this paper are coming from interpretation of data
acquired during surveys realised in the framework of two main projects; (1) BlaSON:
a French-Romanian bilateral project for which two surveys coordinated by IFREMER were carried out on board the French RV “Le Suroît” in 1998 and 2002, (2)
ASSEMBLAGE: a FP5 European project for which two surveys on board the French
RV “Le Marion Dufresne” in 2004 and the Romanian RV “Mare Nigrum” in 2005
were carried out. For all these surveys a differential GPS system was deployed for accurate (about 1 m) positioning and every vessel was equipped with swath bathymetry
systems. Very high-resolution seismic lines were shot simultaneously using a Chirp
sonar system. All data acquisition were synchronized and digitally recorded. The
navigation profiles presented here are displayed in Fig. 6.2.
Together with geophysical surveys, ground truthing was obtained from cores.
Sediment cores have been recovered using Kullenberg-type piston corers. More than
100 cores were collected among which, some reach more than 40 m long of sediment
recovery. Studies are still ongoing on the analyses of the samples.
6.3 Results
6.3.1 Morphological Information
Prior to these important Black Sea campaigns, work and publications reported presence of terraces on many Black Sea margins, from the narrow Caucasus shelves
(Ostrovskiy et al. 1977; Shimkus et al. 1980) to the Northern Turkish shelf (Algan
et al. 2002; Ballard et al. 2000). Among these terraces, shells belonging to past littoral environments were dated between 19,000 to 9,000 years BP (Chepalyga 1984;
Dimitrov 1982; Ostrovskiy et al. 1977; Scherbakov et al. 1978). On the Romanian
continental shelf, Popescu et al. (2004) and Lericolais et al. (2007b) have noticed the
absence of incised river channels below − 90 m water depth where a wave-cut terrace
like morphology was mapped about 100 km far from the Danube delta (Fig. 6.3).
Wave-cut terraces are erosion surfaces created by erosion from wave action indicating the vicinity of the shoreline. Since rivers do not always generate continuous
incised valleys all along the shelf (Lericolais et al. 2001; Talling 2000; Wescott