Academic Journal
The depth of pseudotachylyte formation from detailed thermochronology and constraints on coseismic stress drop variability
| العنوان: | The depth of pseudotachylyte formation from detailed thermochronology and constraints on coseismic stress drop variability |
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| المؤلفون: | Dobson, Kate, Kirkpatrick, J. D., Dobson, K. J., Mark, D. F., Shipton, Z. K., Brodsky, E. E., Stuart, F. M. |
| المصدر: | Dobson , K , Kirkpatrick , J D , Dobson , K J , Mark , D F , Shipton , Z K , Brodsky , E E & Stuart , F M 2012 , ' The depth of pseudotachylyte formation from detailed thermochronology and constraints on coseismic stress drop variability ' , Journal of Geophysical Research: Atmospheres , vol. 117 , no. 6 , B06406 . https://doi.org/10.1029/2011JB008846 |
| سنة النشر: | 2012 |
| المجموعة: | The University of Manchester: Research Explorer - Publications |
| الوصف: | Pseudotachylytes are accepted as recording paleo-seismicity in the rock record. However, the interpretation of the mechanics of faulting based on pseudotachylyte generation is often hindered because the depth at which they form is poorly constrained. Here, we use thermochronology to determine the depth at which pseudotachylytes in the Sierra Nevada, California, formed. The pseudotachylytes formed in ≤ 10 m long patches over a rupture surface, the rest of which comprised cataclasites that did not melt. The age of the pseudotachylytes is found to be 76.6 0.3 Ma (2σ) from 40Ar/ 39Ar dating of pristine vein matrix. A suite of thermochronometers define the temperature-time path of the host rock granodiorite from ∼550 to 60°C. When the pseudotachylytes formed, the ambient temperature was 110 to 160°C, implying a depth of ∼2.4 to 6.0 km under typical geothermal gradients. At these depths, the failure stress on optimally oriented faults with Byerlee friction and hydrostatic pore pressure was ≤51 MPa. Following melting, the dynamic stress acting on the fault is the melt shear resistance, which we calculate to be |
| نوع الوثيقة: | article in journal/newspaper |
| وصف الملف: | application/octet-stream |
| اللغة: | English |
| DOI: | 10.1029/2011JB008846 |
| الاتاحة: | https://research.manchester.ac.uk/en/publications/c25d1068-92a3-4f16-b467-1291bf9981db https://doi.org/10.1029/2011JB008846 https://pure.manchester.ac.uk/ws/files/19966493/POST-PEER-REVIEW-PUBLISHERS.PDF |
| Rights: | info:eu-repo/semantics/openAccess |
| رقم الانضمام: | edsbas.1BFAEEA0 |
| قاعدة البيانات: | BASE |
| DOI: | 10.1029/2011JB008846 |
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