STRATIGRAPHY AND THE GEOLOGIC-FORMATIONAL CORRELATION OF THE GRANULITE COMPLEXES OF THE UKRAINIAN SHIELD Article 3. Stratigraphy of the granulite complexes of the megablocks infrastructure and summary correlation

• Datum: 2020
• Hauptverfasser: Kyrylyuk, V.P., Lysak, A.M., Sivoronov, A.A.
• Format: Artikel
• Sprache: Russisch
• Veröffentlicht: Institute of Geological Sciences, NAS of Ukraine 2020
• Schlagworte: stratigraphy; granulite-gneiss complexes; series; suite; Lower Archean; Ukrainian Shield
• Online Zugang: http://geojournal.igs-nas.org.ua/article/view/196983
• Назва журналу: Geological journal

Granulite-gneiss complexes and their diaphoritic analogs, together with the ultrametamorphic formations that replace them, are the most common on the surface of the basement of the Ukrainian Shield. These complexes are known in all megablocks and most likely have continuous development in the basement of the shield under the younger stratigenic complexes of the Lower Precambrian, which overlap them. In previous articles of the series the stratigraphy of Bug Area and Azov Area granulite complexes is considered, that compose overhead structural stage (suprastructure) of Podolsk and Azov Area megablocks, and also south part of Bug-Ros megablock. Data about composition and distribution of granulite complexes within the limits of Dnepr Area, Ingul and Volyn megablocks are presented in this article. In these megablocks granulite complexes are part of the lower structural stage (infrastructure) and are therefore limited in distribution. Summary geological-formational correlation of all granulite-gneiss complexes of the Ukrainian Shield demonstrates their good compatibility between themselves and with the key section of the Bug Area complexes. The common units for all megablocks, except for Volyn, are the enderbito-gneissic and leucogranulitic formations, and for Volyn megablock, the enderbito-gneissic and kintzigitic formations of the key section. An assumption was made about the formation of the initial strata of granulite-gneiss complexes in specific conditions of a global character that have not re-occurred throughout the Earth’s further development. This provides grounds not only for the geologic-formational, but also for the stratigraphic dating correlation among the disparate granulite-gneiss complexes. Based on the oldest isotope dating results of 3780- 3650 million years from the Bug complex ores, all granulite-gneiss complexes of the Ukrainian Shield belong to the Lower Archean. All more young dating of granulite-gneiss complexes is, most likely, due to their subsequent long and, probably, continuous stay in the conditions of granulite facies and ongoing metamorphism and ultrametamorphism.