The Donbas Fold Belt is the compressionally deformed southeasternmost part of the intracratonic late Paleozoic Dniepr‐Donets rift basin. It is situated in an intracratonic setting but close to the southern margin of the East European Craton, south of which lies the Scythian Platform. A range of igneous rocks from the Donbas Fold Belt and the Scythian Platform were dated by the 40Ar/39Ar method in order to constrain the ages of magmatic activity in these areas, and compare them. The plateau ages from the south margin of the Donbas Fold Belt vary from 151.4 ± 4.7 Ma to 278.1 ± 5.3 Ma, and define three main age groups: Middle‐Late Jurassic, Middle‐Late Triassic, and Early Permian. The age spectra obtained from the Scythian Platform samples are often disturbed as a result of limited alteration. The proposed ages (plateau and pseudoplateau) vary from 174.4 ± 2.1 Ma to 243.7 ± 1.4 Ma, and two major age groups are defined, in Early Carboniferous and Triassic/Jurassic times. The Early Permian (285–270 Ma) and Early Triassic (245–250 Ma) ages of magmatic activity are the same in both areas; in the Late Triassic, the ages of magmatic activity are slightly different (220 and 205 Ma), and they are entirely different thereafter. These data can be interpreted as indicating a mantle plume as common deep magmatic source.

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A Devonian-Early Carboniferous succession comprising thick clastic and carbonate sediments with interbedded volcanics was examined along the southern margin of the Donbas fold belt, Ukraine. Following initial rifting and subsidence, a continental (fluvial, lacustrine) succession was established. This first phase of synrift activity (Eifelian) was accompanied by the extrusion of basalts. In Late Givetian-early Famennian times, half-graben development was pronounced and a series of E-W-trending half-grabens were formed, along with coeval volcanic activity. Subsequent basin subsidence led to the establishment of a broad marine carbonate platform across the region (Late Famennian-Tournaisian-early Viséan). Renewed uplift led to partial exposure and karstification of the platform. This was accompanied by trachyte intrusion and extrusion. The overlying chert-rich unit was probably deposited under lacustrine conditions, although a shelf environment has also been suggested. Renewed tectonic activity along the main basin-bounding fault resulted in the synsedimentary deformation of this unit.

An unconformity has been observed along the Black Sea shelf on seismic reflection profiles and wells which is broadly similar to the one associated with that formed during the Messinian salinity crisis (MSC) in the Mediterranean. Therefore, this intra- (or Middle) Pontian unconformity has been traditionally interpreted as the manifestation of the MSC in the Black Sea Basin. However, the magnitude of the sea-level fall associated with this erosive surface does not appear to be nearly as significant as was assumed previously. Also, the inferred MSC surface itself cannot be easily followed into the palaeo-deep-water basin as a regional unconformity in the same manner as in the Mediterranean. Moreover, around the Black Sea, there is no evidence of major river incisions during the MSC, unlike the well-documented cases in the Mediterranean region. If the MSC evaporites in the Mediterranean indeed deposited in a subaerial setting at the basin floor, the lack of a major drawdown in the Black Sea explains why there are no Messinian evaporites in the Black Sea. Owing to the approximately 500 m MSC sea-level drop the Black Sea basin system, this basin did not even get close to the conditions required for the formation of evaporites in the basin centre. As the magnitude of the sea-level drop and the overall impact of the MSC in the Black Sea is interpreted to be less significant than in the Mediterranean, the risk of breaching pre-existing hydrocarbon traps during the MSC is less than has been suggested before.

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