دورية أكاديمية

Tracking geothermal anomalies along a crustal fault using (U − Th)∕He apatite thermochronology and rare-earth element (REE) analyses: the example of the Têt fault (Pyrenees, France)

التفاصيل البيبلوغرافية
العنوان: Tracking geothermal anomalies along a crustal fault using (U − Th)∕He apatite thermochronology and rare-earth element (REE) analyses: the example of the Têt fault (Pyrenees, France)
المؤلفون: G. Milesi, P. Monié, P. Münch, R. Soliva, A. Taillefer, O. Bruguier, M. Bellanger, M. Bonno, C. Martin
المصدر: Solid Earth, Vol 11, Pp 1747-1771 (2020)
بيانات النشر: Copernicus Publications, 2020.
سنة النشر: 2020
المجموعة: LCC:Geology
LCC:Stratigraphy
مصطلحات موضوعية: Geology, QE1-996.5, Stratigraphy, QE640-699
الوصف: The Têt fault is a major crustal-scale fault in the eastern Pyrenees (France) along which 29 hot springs emerge, mainly within the footwall damage zone of the fault. In this study, (U-Th)/He apatite (AHe) thermochronology is used in combination with rare-earth element (REE) analyses in order to investigate the imprint of hydrothermal activity around two main hot spring clusters (Thuès-les-Bains and St Thomas) and between them. The main goal is to better define the geometry and intensity of the recent thermal anomalies along the fault and to compare them with previous results from numerical modelling. This study displays 99 new AHe ages and 63 REE analyses on single apatite grains from samples collected in the hanging wall (18 to 43 Ma) and footwall (8 to 26 Ma) of the Têt fault. In the footwall, the results reveal AHe age resetting and apatite REE depletion due to hydrothermal circulation along the Têt fault damage zone, near the two hot spring clusters, and also in areas lacking present-day geothermal surface manifestation. These age resettings and element depletions are more pronounced around the Thuès-les-Bains hot spring cluster and are spatially restricted to a limited volume of the damage zone. Outside this damage zone, new modelling of thermochronological data specifies the thermal evolution of the massifs. The footwall model suggests the succession of two main phases of cooling: between 30 and 24 Ma and a second one around 10 Ma. In the hanging wall, little evidence of hydrothermal imprint on AHe ages and REE signatures has been found, and thermal modelling records a single cooling phase at 35–30 Ma. Low-temperature thermochronology combined with REE analyses allows us to identify the spatial extent of a recent geothermal perturbation related to hydrothermal flow along a master fault zone in the eastern Pyrenees, opens new perspectives to constrain the geometry and intensity of geothermal fields, and provides new regional constraints on the cooling history of the footwall and hanging-wall massifs.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1869-9510
1869-9529
Relation: https://se.copernicus.org/articles/11/1747/2020/se-11-1747-2020.pdf; https://doaj.org/toc/1869-9510; https://doaj.org/toc/1869-9529
DOI: 10.5194/se-11-1747-2020
URL الوصول: https://doaj.org/article/9dcc339ff6124f75aa4bf4dae107db9d
رقم الأكسشن: edsdoj.9dcc339ff6124f75aa4bf4dae107db9d
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:18699510
18699529
DOI:10.5194/se-11-1747-2020