A ZOOGENIC BUILDUP FROM THE MIDDLE FRASNIAN (UPPER DEVONIAN) OF THE ZHLOBIN SADDLE (EAST OF BELARUS)

The article provides a brief description and reconstruction of a Middle Frasnian coral-stromatoporoid buildup, uncovered by the Rahachouskaya-742 borehole. It is preserved as a xenolith in younger Devonian volcanic formations of a volcanic pipe in the Zhlobin Saddle. The buildup, at least several tens of meters in diameter, could have represented a bioherm or part of a more complex framework structure. The main rock-forming organisms were Tabulata and Rugosa corals, as well as Stromatoporoidea. The organogenic limestones and secondary dolomites of the buildup are characterized by noticeable porosity, indicating their potential for high reservoir properties. Paleogeographically, this structure is confined to the proposed East Belarusian reef belt of the Semiluki Time (Middle Frasnian).

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