Controls of the Lithospheric Thermal Field of an Ocean-Continent Subduction Zone
- In an ocean-continent subduction zone, the assessment of the lithospheric thermal state is essential to determine the controls of the deformation within the upper plate and the dip angle of the subducting lithosphere. In this study, we evaluate the degree of influence of both the configuration of the upper plate (i.e., thickness and composition of the rock units) and variations of the subduction angle on the lithospheric thermal field of the southern Central Andes (29 degrees-39 degrees S). Here, the subduction angle increases from subhorizontal (5 degrees) north of 33 degrees S to steep (similar to 30 degrees) in the south. We derived the 3D temperature and heat flow distribution of the lithosphere in the southern Central Andes considering conversion of S wave tomography to temperatures together with steady-state conductive thermal modeling. We found that the orogen is overall warmer than the forearc and the foreland and that the lithosphere of the northern part of the foreland appears colder than its southern counterpart.In an ocean-continent subduction zone, the assessment of the lithospheric thermal state is essential to determine the controls of the deformation within the upper plate and the dip angle of the subducting lithosphere. In this study, we evaluate the degree of influence of both the configuration of the upper plate (i.e., thickness and composition of the rock units) and variations of the subduction angle on the lithospheric thermal field of the southern Central Andes (29 degrees-39 degrees S). Here, the subduction angle increases from subhorizontal (5 degrees) north of 33 degrees S to steep (similar to 30 degrees) in the south. We derived the 3D temperature and heat flow distribution of the lithosphere in the southern Central Andes considering conversion of S wave tomography to temperatures together with steady-state conductive thermal modeling. We found that the orogen is overall warmer than the forearc and the foreland and that the lithosphere of the northern part of the foreland appears colder than its southern counterpart. Sedimentary blanketing and the thickness of the radiogenic crust exert the main control on the shallow thermal field (<50km depth). Specific conditions are present where the oceanic slab is relatively shallow (<85 km depth) and the radiogenic crust is thin. This configuration results in relatively colder temperatures compared to regions where the radiogenic crust is thick and the slab is steep. At depths >50km, the temperatures of the overriding plate are mainly controlled by the mantle heat input and the subduction angle. The thermal field of the upper plate likely preserves the flat subduction angle and influences the spatial distribution of shortening.…
Verfasserangaben: | Constanza Rodriguez PicedaORCiDGND, Magdalena Scheck-WenderothORCiDGND, Judith BottORCiDGND, Maria Laura Gomez DacalORCiD, Mauro CacaceORCiDGND, Michael PonsORCiDGND, Claudia PrezziORCiD, Manfred StreckerORCiDGND |
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DOI: | https://doi.org/10.2113/2022/2237272 |
ISSN: | 1941-8264 |
ISSN: | 1947-4253 |
Titel des übergeordneten Werks (Englisch): | Lithosphere / Geological Society of America |
Untertitel (Englisch): | the Southern Central Andes |
Verlag: | GeoScienceWorld |
Verlagsort: | McLean |
Publikationstyp: | Wissenschaftlicher Artikel |
Sprache: | Englisch |
Datum der Erstveröffentlichung: | 13.05.2022 |
Erscheinungsjahr: | 2022 |
Datum der Freischaltung: | 13.03.2024 |
Band: | 2022 |
Ausgabe: | 1 |
Aufsatznummer: | 2237272 |
Seitenanzahl: | 26 |
Fördernde Institution: | Deutsche Forschungsgemeinschaft (DFG); Federal State of Brandenburg; DFG; [STR 373/34-1] |
Organisationseinheiten: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Geowissenschaften |
DDC-Klassifikation: | 5 Naturwissenschaften und Mathematik / 55 Geowissenschaften, Geologie / 550 Geowissenschaften |
Peer Review: | Referiert |
Publikationsweg: | Open Access / Gold Open-Access |
DOAJ gelistet | |
Lizenz (Deutsch): | CC-BY - Namensnennung 4.0 International |