EGU21-3052
https://doi.org/10.5194/egusphere-egu21-3052
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

From moderate earthquakes to continuous aseismic slip, a variety of ways to release strain along the Chaman fault (Pakistan, Afghanistan). 

Manon Dalaison1, Romain Jolivet1,2, and Elenora van Rijsingenn1
Manon Dalaison et al.
  • 1Laboratoire de Géologie - CNRS, Ecole Normale Supérieure - PSL University, Paris, France
  • 2Institut Universitaire de France, Paris, France

Surface fault slip can be continuously monitored at fine spatial resolution from space using InSAR. Based on 5 years of observations (2014-2019), we describe and interpret the InSAR time series of deformation around the Chaman fault, a major strike-slip fault along the boundary between the Indian and Eurasian plates. Aseismic slip was observed on two >100 km long segments, reaching a maximum of 1 cm/yr. In between, a fault segment delimited by a restraining and releasing bend in the fault trace hosted three Mb 4.2, Mw 5.1 and Mw 5.6 earthquakes in our observation period. These earthquakes were followed by significant postseismic slip with characteristic duration between 1.5 to 3 years. Postseismic to coseismic surface slip ratios reach at least 0.6-1.2. In addition, aseismic slip was observed in close spatio-temporal relationship with those earthquakes. Finally, we argue that we detect numerous micro-slip events of Mw<3, although with large uncertainty. We provide an extensive description of the various modes of slip along this plate boundary fault and discuss the mechanical implications of such entangled behavior. 

How to cite: Dalaison, M., Jolivet, R., and van Rijsingenn, E.: From moderate earthquakes to continuous aseismic slip, a variety of ways to release strain along the Chaman fault (Pakistan, Afghanistan). , EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-3052, https://doi.org/10.5194/egusphere-egu21-3052, 2021.

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