- Research Article
- 10.3176/earth.2025.11
- Oct 29, 2025
- Estonian Journal of Earth Sciences
- Ervīns Lukševičs + 4 more
Combined sedimentological and palaeontological studies of the vertebrate fossil-bearing deposits of the Upper Devonian, Upper Famennian Ketleri Formation have provided new data on the sedimentary environment of the deposits, as well as on taxonomic and taphonomic peculiarities of the fossil assemblage. Data from numerical modelling of the Baltic Devonian Basin demonstrate that the sandy deposits of the PavÄri and Varkaļi members form a fan-shaped area resembling a wide delta developed in shallow-marine settings. Fluvial channels and bars with strong tidal influence were identified in a sedimentological study of the PavÄri site, suggesting a tide-influenced fluvial environment. Taphonomic studies indicate that the sedimentary concentrations of well-preserved vertebrate remains were formed under the influence of fluvial and strong tidal processes in a shallow-water environment, most likely in tide-influenced deltaic settings. Trace fossils recognised in the Ketleri and PavÄri-1 sites suggest a brackish-water or marine environment, and thus support the hypothesis. The analysis of rhizocretes from the Varkaļi Member suggests the strong influence of a seasonal climate. Well-preserved plant macroremains have been discovered for the first time during this study in the Ketleri Formation.
- Research Article
- 10.3176/earth.2025.06
- Mar 8, 2025
- Estonian Journal of Earth Sciences
- Samuli Helama + 4 more
Plant-based data from southern Finland were used to reconstruct late Holocene warm-season temperature variability on inter-annual to longer scales. Temperature-sensitive records representing maximum latewood density of Pinus sylvestris tree rings (since AD 760) and phenological stages of several plant species (since AD 1750) explained ~60% and ~70% of instrumentally observed temperature variance, respectively. The value of a multi-proxy approach was demonstrated by statistical models including both variables, which explained ~80% of the temperature variance. Temperatures from the CRUTEM5 and Berkeley datasets had slight variations in their correlativity with proxy data, possibly resulting from their differing spatial representativeness over the proxy sites. Temperature history inferred from maximum latewood densities extended over the past millennium and correlated with previously published data from similar proxy records in Fennoscandia and adjacent areas. These data indicate that the region cooled since the Medieval Climate Anomaly and warmed markedly since the Little Ice Age/Maunder Minimum. In the study region, the magnitude of this long-term warming was 2.1 °C and 2.8 °C, calculated between the coldest and warmest 100-year and 30-year intervals, respectively. Collectively, our results display the potential of plant-based data from low-lying and mild boreal sites to extend our understanding of preindustrial and recent climatic changes.
- Research Article
- 10.3176/earth.2025.06s
- Mar 8, 2025
- Estonian Journal of Earth Sciences
- Samuli Helama + 4 more
- Research Article
- 10.3176/earth.2025.05
- Feb 5, 2025
- Estonian Journal of Earth Sciences
- Juan David Solano-Acosta + 2 more
This research focuses on the geochemical analysis of Paleoproterozoic metasedimentary and metavolcanic units in the Alutaguse region of northern Estonia, shedding light on the geodynamic evolution during the Svecofennian orogeny in eastern Fennoscandia. The metasedimentary units consist of micaceous gneisses (± Grt ± Crd ± Sil), and the metavolcanic units include amphibolites and pyroxenic gneisses. Geochemical analyses utilized both historical and new whole-rock geochemical data. Weathering indices indicated their applicability for provenance studies and tectonic setting analyses. Metasediments are classified by their silica content: high-SiO2 (>63 wt%) metasediments resemble litharenites, implying higher maturity and felsic origins akin to the upper continental crust reference; low-SiO2 (
- Research Article
- 10.3176/earth.2025.s05
- Feb 5, 2025
- Estonian Journal of Earth Sciences
- Juan David Solano-Acosta + 2 more
Supplementary files 1 and 2 are designed to provide an in-depth analysis, including the complete analyzed geochemical dataset of the Alutaguse zone.
- Research Article
1
- 10.3176/earth.2025.04
- Jan 31, 2025
- Estonian Journal of Earth Sciences
- Normunds Stivrins + 2 more
Latviaâs peatlands play an important role in achieving the countryâs climate goals and preserving natural diversity. Approximately 10% of Latviaâs territory is covered by peatlands, more precisely defined as peat deposits. However, outdated inventories of these peatlands hinder the development of sustainable policies for managing natural recourses. This lack of data also complicates efforts to predict the extent of fens and assess their potential contribution to climate change mitigation, such as through rewetting activities. In this study, we assessed the extent of fens in one of Latviaâs largest municipalities â Ogre. After a feasibility study using GIS tools, fen peat deposits were randomly selected and surveyed in the field to determine the type, thickness, and characteristics of the peat. Among the 20 sites surveyed, only five corresponded to fen peat deposits (with a peat layer of at least 30 cm), and only one of these qualified as a fen also in terms of vegetation and moisture regime. Existing fen peat deposits are subject to intensive erosion, mineralization, and decomposition, leading to greenhouse gas emissions. The results indicate that there are significantly fewer fen peat deposits than previously assumed, and a detailed analysis of their extent, involving field inspection and verification at the national level, is needed.
- Research Article
- 10.3176/earth.2025.03
- Jan 13, 2025
- Estonian Journal of Earth Sciences
- Elisa Toivanen + 4 more
The Orijärvi area within the Paleoproterozoic Uusimaa belt contains volcanic and minor sedimentary formations, providing valuable insights into the oldest Svecofennian crust in southern Finland. Previously, felsic volcanic rocks from the Orijärvi, Kisko and Toija formations have been dated at 1895 ± 3, 1878 ± 4 and 1878 ± 4 Ma, respectively. In the present study, the Sorvasto sample from the southern boundary of the Kisko formation yields a zircon age of 1885 ± 5 Ma and a titanite age of 1800 ± 15 Ma. The zircon age falls within the interval between previously obtained age determinations and is coeval with the common Svecofennian crustal growth stage. The Kavasto sample from the western part of the area yields a zircon age of 1878 ± 6 Ma and a titanite age of 1796 ± 4 Ma. The zircon age corresponds to those obtained for similar rock types in the Toija and Ahdisto formations. Picritic interlayers occur within all these successions and are here interpreted as belonging to the same Toija formation. We tentatively infer that the Toija and Salittu formations, together with the overlying sedimentary rocks, can be traced to the West Uusimaa area in the east and the Turku area in the west. The titanite ages near 1.80 Ga reflect cooling or reheating events.
- Research Article
- 10.3176/earth.2025.07
- Jan 1, 2025
- Estonian Journal of Earth Sciences
- T Märss
- Research Article
- 10.3176/earth.2025.08
- Jan 1, 2025
- Estonian Journal of Earth Sciences
- Enn Karro + 6 more
- Research Article
1
- 10.3176/earth.2025.02
- Dec 31, 2024
- Estonian Journal of Earth Sciences
- Ilona Šakurova + 6 more
We analyze the spatio-temporal dynamics of sand relocation for beach nourishment in the low-energy coastal segment north of the Port of KlaipÄda, eastern Baltic Sea, under mild wave conditions, with significant wave heights below 0.9 m and water level variations from â30 to 44 cm with respect to the long-term average. In summer 2022, about 180 000 m3 of sand was added approximately 120 m from the shore at water depths of 2â3.5 m to form a 750 m long underwater bar. Sand relocation is evaluated based on repeated water depth measure ments along 114 cross-shore coastal profiles. Some sand was rapidly transported to greater depths, down to about 6 m, even though wave conditions were particularly mild. The pre dominant sand motion was directed offshore, and characteristically for the area, wave-driven sediment transport was directed to the north. The analysis confirms that even very mild wave conditions can substantially relocate large volumes of deposited sand in shallow water, both offshore and onshore, from its original location during the initial adjustment phase following nourishment.