Unraveling sea-level variations and tectonic uplift in wave-built marine terraces, Santa Maria Island, Chile
- The architecture of coastal sequences in tectonically-active regions results mostly from a combination of sea-level and land-level changes. The objective of this study is to unravel these signals by combining sequence stratigraphy and sedimentology of near-shore sedimentary sequences in wave-built terraces. We focus on Santa Maria Island at the south-central Chile margin, which hosts excellent exposures of coastal sediments from Marine Isotope Stage 3. A novel method based on statistical analysis of grain-size distributions coupled with fades descriptions provided a detailed account of transgressive-regressive cycles. Radiocarbon ages from paleosols constrain the chronology between >53 and similar to 31 cal ka BP. Because the influence of glaciations can be neglected, we calculated relative sea-level curves by tying the onset of deposition on a bedrock abrasion platform to a global sea-level curve. The observed depositional cycles match those predicted for uplift rates between 1.2 and 1.8 m/ka. The studied sedimentary units representThe architecture of coastal sequences in tectonically-active regions results mostly from a combination of sea-level and land-level changes. The objective of this study is to unravel these signals by combining sequence stratigraphy and sedimentology of near-shore sedimentary sequences in wave-built terraces. We focus on Santa Maria Island at the south-central Chile margin, which hosts excellent exposures of coastal sediments from Marine Isotope Stage 3. A novel method based on statistical analysis of grain-size distributions coupled with fades descriptions provided a detailed account of transgressive-regressive cycles. Radiocarbon ages from paleosols constrain the chronology between >53 and similar to 31 cal ka BP. Because the influence of glaciations can be neglected, we calculated relative sea-level curves by tying the onset of deposition on a bedrock abrasion platform to a global sea-level curve. The observed depositional cycles match those predicted for uplift rates between 1.2 and 1.8 m/ka. The studied sedimentary units represent depositional cycles that resulted in reoccupation events of an existing marine terrace. Our study demonstrates wave-built marine terrace deposits along clastic shorelines in temperate regions can be used to distinguish between tectonic uplift and climate-induced sea-level changes.…
Verfasserangaben: | Julius Jara-MunozORCiDGND, Daniel MelnickORCiDGND |
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DOI: | https://doi.org/10.1016/j.yqres.2014.10.002 |
ISSN: | 0033-5894 |
ISSN: | 1096-0287 |
Titel des übergeordneten Werks (Englisch): | Quaternary research : an interdisciplinary journal |
Verlag: | Elsevier |
Verlagsort: | San Diego |
Publikationstyp: | Wissenschaftlicher Artikel |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2015 |
Erscheinungsjahr: | 2015 |
Datum der Freischaltung: | 27.03.2017 |
Freies Schlagwort / Tag: | Coastal sedimentation; Marine terraces; Sea-level change; Tectonic uplift; Terrace reoccupation; Wave-built terraces |
Band: | 83 |
Ausgabe: | 1 |
Seitenanzahl: | 13 |
Erste Seite: | 216 |
Letzte Seite: | 228 |
Fördernde Institution: | Federal Ministry of Education and Research; MARISCOS (MAule eaRthquake: Integration of Seismic Cycle Observations and Structural investigations) project from the German Science Foundation (DFG) [STR 373/30-1]; German Science Foundation (DFG) [ME 3157/2-2] |
Organisationseinheiten: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Geowissenschaften |
Peer Review: | Referiert |
Name der Einrichtung zum Zeitpunkt der Publikation: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Erd- und Umweltwissenschaften |