Monitoring of temporal seismic velocity changes in the North Anatolian Fault zone using data derived scattering properties
- 1Université Grenoble Alpes, Institut des Sciences de la Terre, Grenoble, France (chantal.van-dinther@univ-grenoble-alpes.fr)
- 2IRAP-CNRS, Université Paul Sabatier Toulouse 3
Monitoring of temporal seismic velocity changes can provide us with information on the mechanical state of the Earth’s crust due to processes of stress build-up and release.
In current work, we use the Dense Array of North Anatolia [1], which has been continuously recording from May 2012 until October 2013, to analyse the spatio-temporal variations of seismic velocity changes in the North Anatolian Fault zone (NAF). We compute daily ambient-noise cross-correlation functions for all 63 three-component stations in the frequency band between 0.1 – 1 Hz.
To retrieve spatial distribution of seismic velocity changes in such an inhomogeneous fault zone, we go beyond the simple linear travel-time shifts approximation and homogeneous sensitivity kernel. We therefore invert for the travel-time shifts at different lag-times. Furthermore, we use sensitivity kernels for media with inhomogeneous scattering properties. The scattering properties for the sensitivity kernels are derived from the data: a scattering mean free path inside the fault zone (northern strand of NAF) of ∼ 10 km and ∼ 150 km outside the fault zone, the attenuation coefficient inside and outside the fault zone are 80 and 100 respectively.
[1] DANA. Dense array for north anatolia. International Federation of Digital Seismograph Networks doi:10.7914/SN/YH2012, 2012.
How to cite: van Dinther, C., Campillo, M., Margerin, L., and Lecointre, A.: Monitoring of temporal seismic velocity changes in the North Anatolian Fault zone using data derived scattering properties, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-15195, https://doi.org/10.5194/egusphere-egu2020-15195, 2020.
This abstract will not be presented.