| Titre | Effects of fluid circulation in subducting crust on Nankai margin seismogenic zone temperatures |
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| Auteur | Spinelli, G A; Wang, K |
| Source | Geology vol. 36, no. 11, 2008 p. 887-890, https://doi.org/10.1130/G25145A.1 |
| Image |  |
| Année | 2008 |
| Séries alt. | Secteur des sciences de la Terre, Contribution externe 20080351 |
| Éditeur | Geological Society of America |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1130/G25145A.1 |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Région | Nankai Margin; Nankai Trough |
| Lat/Long OENS | 132.0000 137.0000 34.5000 31.0000 |
| Sujets | zones de subduction; subduction; temperature; températures géothermiques; anomalies; croûte océanique; perméabilité; système hydrothermal; sismicité; caractéristiques structurales; failles; zones de
failles; établissement de modèles; modèles; tectonique; géologie structurale |
| Illustrations | cartes de localisation; graphiques; graphiques; coupes transversales |
| Programme | Réduction des risques dus aux aléas naturels |
| Diffusé | 2008 01 01 |
| Résumé | (disponible en anglais seulement)
Vigorous fluid circulation maintained in newly subducted ocean crust significantly affects subduction zone temperatures on the Nankai margin, Japan. The shallow
part of the igneous ocean crust is pervasively fractured and thus highly permeable, allowing vigorous hydrothermal circulation. This circulation has been recognized as an important control on the thermal budget and evolution of ocean crust worldwide.
However, existing subduction zone thermal models either do not include hydrothermal circulation in ocean crust or assume that it abruptly stops upon subduction. Here, we use a conductive proxy to incorporate the thermal effects of high Nusselt number
fluid circulation in subducting crust into a subduction zone thermal model. Hydrothermal circulation reduces temperatures in the seismogenic zone of the Nankai margin plate boundary fault by ~20 °C at the updip limit of seismicity and ~100 °C at the
downdip limit. With improved thermal models for subduction zones that include the effects of hydrothermal circulation in subducting crust, estimates of metamorphic reaction progress and interpretations of fault zone processes on various margins may
need to be revisited. |
| GEOSCAN ID | 225735 |
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