DACIAN BASIN - GeoEcoMar

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Chapter 11. From Brackish-Marine to Continental-Fluvial Depositional Environment
Crowley (1994) argued that the lower shoreface of a littoral unit forced to prograde
because of a sea-level fall, should show a sharp, not a transitional basal limit.
Another explanation of the Dacian Basin fill resorts to the sediment filling out
process. Indeed, the Dacian Basin could have been almost full with accumulated
sediments by the time the Early Dacian shoreline began to migrate. The 700.000
year time lap might be enough for the sediment accumulation to fill out the eastern
part of the basin.
The concept of the transition to continental environment due to the filling out
of the Dacian Basin during the Dacian time does not provide an explanation to the
possible west to east gradual filling out of the basin. Why should the western part
of the basin fill out first, when the bulk of sediment accumulation is in the eastern
part of the basin? Was the eastern part of the Dacian Basin a separated depressional
area as a result of the subsidence process?
The role of the subsidence in any scenario of the Dacian Basin fill might be very
important. The high subsidence was restricted to the Focşani-Buzău area, conferring
individuality to the north-eastern part of the Dacian Basin. Subsidence may
explain why the northern part of the basin was the last to be drained out by forced
regression. Also, subsidence could provide the explanation of the eastern part of
the basin which continued to accumulate sediment, while the western Dacian Basin
was filled out.
The complete explanation of the Dacian Basin closure and the identification of
the forcing factors which controlled the process require more data.