/SH-Ambient-Noise-NatComm

The ambient noise modelling codes developed for the paper Fluid migrations and volcanic earthquakes from depolarized ambient noise, Petrosino & De Siena, accepted n Nature: Communications.

Primary LanguageMATLABGNU General Public License v2.0GPL-2.0

DOI

SH-wave simulation code for ambient noise polarization

The ambient noise modelling codes developed for the paper Fluid migrations and volcanic earthquakes from depolarized ambient noise, submitted to Nature: Communications and available as pre-print on Research Square

Content and requirements

The simulation works in Matlab version 2019a and requires the Image Processing, Mapping and Wavelet toolboxes.

The folder contains four subfolders:

FarLine to obtain results from a line of ambient noise sources in the far field (plane wave).

NearCoastline to obtain results from a circle of ambient noise sources in the near field (circular wave).

FigureED8 to obtain the corresponding Figure.

idw with the corresponding function and licence.

The FarLine and NearCoastline folders are used for modelling, inside each of them there are two more subfolders with the names:

Homogeneous to obtain results for an homogeneous model (constant shear modulus).

Heterogeneous to obtain results for an heterogeneous model (shear modulus that varies depending on polarisation results).

Use

  1. Download the package.
  2. Enter the folder Modelling.
  3. Enter the folder corresponding to the source distribution you want to simulate (FarLine or NearCoastline).
  4. Enter the folder corresponding to either the homogeneous or heterogeneous case.
  5. Run the file CF_noise_sources_?.m where ? corresponds either to Line or CircleN.

Outputs

The simulation will produce a video showing noise propagation (.avi), a figure showing the variations of shear modulus (.tiff), and a .mat file that contains the simulated noise data at all stations considered (.mat) and a figure representing the corresponding seismograms (.fig).

Simulation Time

Each simulation takes about 2 hours and 15 minutes on a Macbook Pro, 2,3 GHz, 8-Core Intel Core i9 with 32 Gb of memory.

Reproduction Instructions

To reproduce the panels in Extended Data Fig. 8a,b, use the codes in Folder Modellin/FigureED8. This contains the results of the Data Processing folder (available in the in the Open Science Framework). The codes were applied to the simulated noise data in .mat format.