DACIAN BASIN - GeoEcoMar

10.5 Conclusions
After the development of the two depocenters, the control of the sediment
filling process was dominated by the westward tilting of the Dacian Basin axial
zone. The two depocenters were located at both ends of the inclined sedimentary
trench. Being positioned at the base of the general sedimentary slope of the basin,
the western depocenter was not exposed to important morphologic changes
(except for the southward extinction). Its main role was to accumulate the detrital
material supplied by the low relief western source-area of the Carpathians to the
limit of its accommodation space.
The eastern Dacian Basin depocenter had a complex evolution. Being affected
by high subsidence, the eastern depocenter acted as a huge sediment trap, being
able to store Late Neogene sediments with a total thickness of several kilometers.
The other role played by the eastern depocenter was controlled by the progressive
westward deepening of the sedimentary trench which created a sedimentary
slope. Being positioned upslope the eastern Dacian Basin depocenter acted as a
sediment conveyor. The detrital material, which exceeded the storing capacity of
the eastern depocenter, was progressively transferred down slope toward the sediment
deficient area between the eastern and western depocenters. Being initially
out of the reach of the sediments supplied by the two Carpathian source-areas, the
area in between the depocenters, developed an excessive accommodation space
during the initial sediment filling stage. The isopach maps (Saulea et al., 1969) (Figs.
10.1; 10.2; 10.10) show the evolution of the process, which led to the filling of this
inter-depocenter area, and the implicit sediment fill of the brackish-marine Dacian
Basin.
During the existence of the Dacian Basin trench the Carpathians-derived sediment
had to be transported longitudinally along the trench elongation and parallel
to the orientation of the mountain range. After the sedimentary trench of the Dacian
Basin was completely filled, the sediments supplied by the Carpathians continued
to accumulate at the base of the mountain. The new post-fill stage allowed
the direct southern transfer of the sediments transversally from the Carpathians.
10.5 CONCLUSIONS
The sediment thickness pattern during the development of the Dacian Basin in the
Late Neogene shows two separate areas of sedimentary accumulation: the eastern
depocenter and the western depocenter.
The initial appearance of two synchronous and separated depocenters represent
the characteristic of the Dacian Basin sediment fill evolution. This feature was
imposed by the existence of two separated Carpathian source-areas located in the
Southern Carpathians and in the southern part of the Eastern Carpathians.
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