Journal metrics

Journal metrics

  • IF value: 4.165 IF 4.165
  • IF 5-year value: 4.075 IF 5-year 4.075
  • CiteScore value: 4.28 CiteScore 4.28
  • SNIP value: 1.501 SNIP 1.501
  • SJR value: 1.060 SJR 1.060
  • IPP value: 4.21 IPP 4.21
  • h5-index value: 29 h5-index 29
  • Scimago H index value: 27 Scimago H index 27
Discussion papers | Copyright
https://doi.org/10.5194/se-2018-84
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Research article 10 Sep 2018

Research article | 10 Sep 2018

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Solid Earth (SE).

Advecting heating by hot fluids of an Alpine fissure in Lauzière Granite (Belledonne massif, Western Alps)

Emilie Janots1,2, Alexis Grand'Homme1, Matthias Bernet1, Damien Guillaume3, Edwin Gnos4, Marie-Christine Boiron5, Magali Rossi6, Anne-Magali Seydoux-Guillaume3, and Roger De Ascenção Guedes7 Emilie Janots et al.
  • 1Univ. Grenoble Alpes, CNRS, IRD, IFSTTAR, ISTerre, 38000 Grenoble, France
  • 2Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität Munich, Luisenstr, 37, 80333 Munich, Germany
  • 3Univ Lyon, UJM-Saint-Etienne, UCA, CNRS, IRD, LMV UMR 6524, 42023, SAINT-ETIENNE, France
  • 4Natural History Museum of Geneva, 1 route de Malagnou, 1208 Geneva, Switzerland
  • 5Université de Lorraine, CNRS, GeoRessources, 54000 Nancy, France
  • 6Univ. Grenoble Alpes, Univ. Savoie Mont-Blanc, CNRS, EDYTEM, 73 000 Chambéry
  • 7Editions du Piat, Glavenas, 43200 Saint-Julien-du-Pinet, France

Abstract. A multi-method approach investigation in the Lauzière granite, located in the external Belledonne massif of the French Alps, reveals unusually hot hydrothermal conditions in vertical open fractures (Alpine-type clefts), caused by advective heating. The host-rock granite shows sub-vertical mylonitic microstructures and partial retrogression at temperatures of <400°C during Alpine tectonometamorphism. Novel zircon fission-track (ZFT) data in the granite give ages at 16.3±1.9 and 14.3±1.6Ma, confirming that Alpine metamorphism was high enough to reset the pre-alpine cooling ages and that the Lauzière granite had already cooled below <240–280°C and was exhumed to <10km at that time. Novel microthermometric data and chemical compositions of fluid inclusions obtained on millimetric monazite and on quartz crystals from the same cleft indicate early precipitation of monazite from a hot fluid at T>410°C, followed by a main stage of quartz growth at 300–320°C and 1.5–2.2kbar. Previous Th-Pb dating of cleft monazite at 12.4±0.1Ma clearly indicates that this hot fluid infiltration took place significantly later than the peak of the Alpine metamorphism. Advective heating due to the hot fluid caused rejuvenation of the ZFT age at 10.3±1.0Ma in the cleft hanging wall. The results attest of highly dynamic fluid pathways, allowing the circulation of deep mid-crustal fluids, 150–250°C hotter than the host-rock, affecting the thermal regime at the wall-rock of the Alpine-type cleft for a duration of 1–3My. Such advecting heating may represent a pitfall source for exhumation reconstructions.

Emilie Janots et al.
Interactive discussion
Status: open (until 26 Oct 2018)
Status: open (until 26 Oct 2018)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Emilie Janots et al.
Emilie Janots et al.
Viewed
Total article views: 316 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
281 32 3 316 1 2
  • HTML: 281
  • PDF: 32
  • XML: 3
  • Total: 316
  • BibTeX: 1
  • EndNote: 2
Views and downloads (calculated since 10 Sep 2018)
Cumulative views and downloads (calculated since 10 Sep 2018)
Viewed (geographical distribution)
Total article views: 316 (including HTML, PDF, and XML) Thereof 313 with geography defined and 3 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited
Saved
No saved metrics found.
Discussed
Latest update: 18 Oct 2018
Publications Copernicus
Download
Short summary
This study reveals the existence of advecting heating due to hot fluid circulations in a Alpine cleft (open fissure partly filled by hydrothermal crystals) of the external crystalline massif in the Western Alps. The source of the fluid is estimated > 6 km deeper compared to the granitic host-rock. This fluid circulation locally impacts the thermal regime and resets the zircon fission track thermochronometer. It demonstrates the existence of very efficient fluid pathways at mid-crustal conditions.
This study reveals the existence of advecting heating due to hot fluid circulations in a Alpine...
Citation
Share