| Titre | Chronology of Quaternary shoreline progradational sequences related to eustatic sea-level changes: sedimentation and subsidence in Saronikos Gulf, Greece |
| |
| Auteur | Foutrakis, P M; Anastasakis, G; Piper, D J W |
| Source | Marine Geology vol. 428, 106278, 2020 p. 1-21, https://doi.org/10.1016/j.margeo.2020.106278 |
| Image |  |
| Année | 2020 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20200130 |
| Éditeur | Elsevier |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1016/j.margeo.2020.106278 |
| Media | papier; en ligne; numérique |
| Formats | pdf; html |
| Région | Saronikos Gulf; Aegean Sea |
| Lat/Long OENS | 20.0000 30.0000 40.0000 35.0000 |
| Lat/Long OENS | 23.8333 23.8333 38.1667 37.5000 |
| Sujets | interprétations géophysiques; interpretations sismiques; profils sismiques; carottes; carottes de sédiment marin; paléogéographie; Pléistocène; Pliocène; stratigraphie systématique; changements du niveau
de la mer; antecedents de sedimentation; débit de sedimentation; antécédents tectoniques; affaissement; formation de failles; plis; sédiments marins; géologie du socle; caractéristiques structurales; failles; biseaux sédimentaires; géochronologie;
géologie marine; géologie des dépôts meubles/géomorphologie; stratigraphie; sédimentologie; tectonique; Nature et environnement; Sciences et technologie; Phanérozoïque; Cénozoïque; Quaternaire; Tertiaire |
| Illustrations | cartes de localisation; tableaux; profils sismiques; échelles stratigraphiques; diagrammes stratigraphiques |
| Diffusé | 2020 06 23 |
| Résumé | (disponible en anglais seulement)
The stacking pattern of shoreline progradational sequences in subsiding basins have been used as a chronologic tool in the Mediterranean region. Most previous
studies have used a few key seismic lines seaward of deltas, where the record is complicated by deltaic distributary switching. Southeastern Saronikos Gulf, in the western Aegean Sea at the northwestern end of the South Aegean Arc, lacks large river
input of sediment. The ENE-WSW and NW-SE trending neotectonic Aegina and Methana basins lie between the tectonically active Gulf of Corinth and the relatively stable Cyclades plateau. New high-resolution seismic profiles from southeastern Saronikos
Gulf have been interpreted according to the principles of seismic and sequence stratigraphy. Alpine basement and marine Pliocene sediments have been recognized in the surrounding basin margins and more than 300 m and 150 m of unconsolidated sediments
have been mapped in Aegina and Methana basin respectively. Progradational clinoforms that toplap against transgressive surfaces, have been traced along strike, leading to the establishment of a robust chronostratigraphic framework further controlled
by sedimentation rates as extracted from cores. Southeastern Saronikos Gulf poses an outstanding example of development of progradational wedges formed within a microtidal, wave dominated regime of low sedimentation rates, between 2.8 cm/ka and 3.2
cm/ka, within the framework of low subsiding basins with rates between 0.03 and 0.31 m/ka. In this environment, more than 180 well preserved shoreline progradational units, with attributes similar to the ones reported from the Aegean and Eastern
Mediterranean seas, have been mapped and correlated to sea level lowstands back to 866 ka. Deeper Mid-Pleistocene progradational units are also recognized, tentatively back to 1.4 Ma. Subsidence rate shows a dramatic decrease in the last 1 Ma and
significant numbers of faults became inactive during the last 130 ka. In Early-Middle Quaternary, Methana basin was an isolated lake and extended terrestrial areas were shaped in the Poros-Agios Georgios plateau during sea level lowstands. Aegina
basin was continuously connected to the Aegean through the Agios Georgios fault valley. This study demonstrates the robustness of chronology based on stacked shoreline progradational sequences and its applicability to determining rates of tectonic
subsidence. |
| Sommaire | (Résumé en langage clair et simple, non publié et disponible en anglais seulement)
This publication focuses on studying the shoreline patterns in the southeastern Saronikos Gulf in the western
Aegean Sea. The researchers used high-resolution seismic data and the principles of seismic and sequence stratigraphy to understand how the shoreline changed over time.
Their main goal was to establish a solid timeline of how the coastline
evolved. They found more than 180 well-preserved shoreline units that extend back to around 866,000 years ago. They also identified older units dating back to approximately 1.4 million years ago.
One of the significant findings is that the rate of
land sinking into the sea decreased dramatically over the last 1 million years. They also discovered that some faults in the area became inactive during the past 130,000 years. This information helps us understand the geological history and tectonic
activity in the region.
The scientific impact of this publication is that it demonstrates the reliability of using shoreline patterns to create a timeline of geological changes. This can be helpful for studying how coastlines have evolved and
understanding the rates of land sinking into the sea. It's also important for evaluating tectonic subsidence, which can have implications for understanding geological processes and assessing potential geological hazards in the area. |
| GEOSCAN ID | 326700 |
|
|