Carbonate sedimentary environments in the epeiric Baltic Devonian Basin: Pļaviņas Formation, Lower Frasnian

Abstract

This study focuses on a detailed facies analysis of the Pļaviņas Formation (Upper Devonian, Lower Frasnian) and the interpretation of their sedimentary environments. The study area is located in the northwestern part of the Main Devonian Field, including the territory of Latvia and the southeastern part of Estonia. Facies analyses primarily rely on geological section documentation, macro-scale sample studies, and various methods, such as X-ray diffraction, X-ray fluorescence, total organic carbon analysis, biomarker analysis, and carbon and oxygen stable isotope analysis. Shallow-water sedimentation occurs across all studied areas of the Baltic Devonian Basin. The basin territory exhibits multiple areas with diverse hydrodynamic activities, leading to fluctuations in environmental energy levels during the study period. Notably, the lagoonal to tidal flat environment is particularly related to the northeastern part of the study area, especially within the Sēlija and Atzele members of the Pļaviņas Formation.

Keywords

• dolomites
• sedimentology
• facies analysis
• epeiric basin
• tidal influence
• carbon and oxygen stable isotopes