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| Titel |
Transient uplift of a long-term quiescent coast inferred from raised fan delta sediments |
| VerfasserIn |
Andrea Madella, Romain Delunel, Onno Oncken  , Sönke Szidat, Fritz Schlunegger |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250142923
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| Publikation (Nr.) |
 EGU/EGU2017-6602.pdf |
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| Zusammenfassung |
| We present the first example of a short-term uplift transient within the long-term subsiding forearc of the Arica Bend, northernmost Chile. We date through radiocarbon a storm deposit embedded into fan delta sediments, which were deposited close to sea level and are now located 50 m higher. The radiocarbon age is ca. 10 ka, which yields an average uplift rate of about 5 mm/yr. The section, in addition, is cut by the Lluta River, whose long profile shows geomorphic response to coastal uplift. The coast of the Arica bend is characterized by Myr-scale relative subsidence and current GPS-surveyed quiescence. We therefore interpret the inferred uplift signal to represent a transient increase in uplift rates during the Holocene. Similar short-term transients have been globally documented in relation to various subduction zones, although their causes still remain a matter of debate and need further investigation. We propose that periods of increased surface uplift may occur also in long-term quiescent forearcs, possibly due to temporal variations of plate interface strength that induce thickening beneath the coast. |
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