MC Kernel

Authors:

Simon Stähler, Martin van Driel, Ludwig Auer, Kasra Hosseini, Tarje Nissen-Meyer

License:

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 3 of the License.

Acknowledgements:

If you use this program for your work, please cite:

Simon C. Stähler, Martin van Driel, Ludwig Auer, Kasra Hosseini, Karin Sigloch, and Tarje Nissen-Meyer: MC Kernel: Broadband Waveform Sensitivity Kernels for Seismic Tomography, Geophysical Research Abstracts, Vol. 18, EGU2016-7020-2, 2016

Download

To download the current developer version, use git clone

git clone https://github.com/seismology/mc_kernel

Prequisites

MC Kernel needs a recent Fortran compiler (gfortran 4.8 or later), an MPI installation, the NetCDF library for accessing the wavefield files, the FFTW library for Fourier transforms and LAPACK, because we were too lazy to write a matrix inversion routine ourselves. The installation of these libraries can be done by hand on desktop machines or using modules on HPC environments. The recommended submit script uses Python and needs NetCDF4

Ubuntu/Debian Linux

Since Ubuntu 14.04LTS, the system libraries can be used:

- sudo apt-get install gfortran libnetcdff5 libnetcdf-dev libfftw3-dev liblapack-dev libblas-dev openmpi-bin libopenmpi-dev

MacOS X

We recommend using Homebrew to download and compile the necessary libraries. Be careful to add the --with-fortran argument while installing any library. Otherwise, only C libraries are installed. If you did install the libraries before without the --with-fortran argument, it may be necessary to remove and reinstall them.

HPC environments

Be sure to load modules for Fortran, NetCDF, FFTW and LAPACK. On SuperMUC, the necessary commands are

module load fortran
module load netcdf/mpi
module load fftw
module load mkl

AxiSEM wavefields

Using the code requires computation of a global seismic wavefield using AxiSEM. Please refer to the AxiSEM documentation on how to do this. An set of example wavefields with a dominant period of 40s can be downloaded:

wget https://www.geophysik.uni-muenchen.de/~staehler/kerner_wavefields.tar.bz2
tar -xvf kerner_wavefields.tar.bz2

Installation

Change into the download directory and copy the included template files into the main directory

cd kerner
./copy_templates.sh

The file make_mc_kerner.macros allows you to modify the compiler name and compiler flags according to your system. To compile, use

make

and afterwards

make check

to run a set of tests (wavefields downloaded in the previous step are necessary for the tests to complete).

Usage

To run the code, a convenient submit script is available:

python submit.py -n NSLAVES JOB_NAME

This creates a run directory JOB_NAME, puts the default input files there and starts a MPI job with one master and NSLAVES worker tasks. In this simple form, it uses default values stored in the files CMTSOLUTION, receivers.dat, filters.dat and stf_20s.dat together with AxiSEM wavefields in ./wavefield/fwd and ./wavefield/bwd.
Modifying the settings for the run is possible by setting one of the options of submit.py, which can be queried by

python submit.py -h

Plot results

MC Kerner comes with a set of simple Python plotting scripts to visualize kernels and the seismograms they are based on. They can be found in the folder pyfiles and need a few extra programs to run:

Paraview (version >= 4.3)
Python packages matplotlib and wand

To run the scripts change into the job directory

cd JOB_DIR

and run

python ../pyfiles/plot_all_seismograms.py
pvpython ../pyfiles/plot_all_kernels.py
python ../pyfiles/create_composites.py

The last script creates a composite image like the one below:

FAQs

Anaconda interference

The python package manager Anaconda installs his own version of gfortran, which interferes with the system version and the MPI libraries. A solution is to replace the compiler name FC and the MPIRUN variable in make_mc_kerner.macros with absolute paths

FC = /usr/bin/mpif90