Repeating earthquakes search and analysis.

Copyright (c) 2021-2024 Claudio Satriano satriano@ipgp.fr

Requake is a command line tool to search and analyse repeating earthquakes.

It can either scan an existing earthquake catalog to search for similar events, or perform template matching on a continuous waveform stream.

Catalogs and waveforms can be read from local files or downloaded using standard FDSN web services.

Requake is written in Python and uses ObsPy as backend.

The latest release of Requake is available on the Python Package Index.

You can install it easily through pip:

pip install requake

If you need a recent feature that is not in the latest release (see the unreleased section in CHANGELOG), you want to use the more recent development snapshot from the Requake GitHub repository.

The easiest way to install the most recent development snapshot is to download and install it through pip, using its builtin git client:

pip install git+https://github.com/SeismicSource/requake.git

Run this command again, from times to times, to keep Requake updated with the development version.

If you want to take a look at the source code (and possibly modify it 😉), clone the project using git:

git clone https://github.com/SeismicSource/requake.git

or, using SSH:

git clone git@github.com:SeismicSource/requake.git

(avoid using the "Download ZIP" option from the green "Code" button, since version number is lost).

Then, go into the requake main directory and install the code in "editable mode" by running:

pip install -e .

You can keep your local Requake repository updated by running git pull from times to times. Thanks to pip's "editable mode", you don't need to reinstall Requake after each update.

Requake is based on a single executable, aptly named requake 😉.

To get help, use:

requake -h

The different running modes are specified as "verbs" (positional arguments). Currently supported verbs are:

sample_config       write sample config file to current directory and exit
read_catalog        read an event catalog from web services or from a file
print_catalog       print the event catalog to screen
scan_catalog        scan an existing catalog for earthquake pairs
print_pairs         print pairs to screen
plot_pair           plot traces for a given event pair
build_families      build families of repeating earthquakes from a catalog
                    of pairs
print_families      print families to screen
plot_families       plot traces for one ore more event families
plot_timespans      plot family timespans
plot_cumulative     cumulative plot for one or more families
map_families        plot families on a map
flag_family         flag a family of repeating earthquakes as valid or not
                    valid. Note that all families are valid by default
                    when first created
build_templates     build waveform templates for one or more event
                    families
scan_templates      scan a continuous waveform stream using one or more
                    templates

Certain running modes (e.g., plot_pair) require further arguments (use, e.g., requake plot_pair -h to get help).

Requake supports command line tab completion for arguments, thanks to argcomplete. To enable command line tab completion, add the following line to your .bashrc or .zshrc:

eval "$(register-python-argcomplete requake)"

The first thing you will want to do is to generate a sample config file:

requake sample_config

Edit the config file according to your needs, then read or download the event catalog:

requake read_catalog

or

requake read_catalog CATALOG_FILE

Now, build the catalog of event pairs with:

requake scan_catalog

Once done (it will take time!), you are ready to build repeating earthquake families:

requake build_families

• requake scan_catalog took 53 minutes on my 2.7 GHz i7 MacBook Pro to process 14,100,705 earthquake pairs. Dowloaded traces are cached in memory to speed up execution. Processing is not yet parallel: some improvements might come in future versions, when parallelization will be implemented.

• requake build_families is fast™.

If you used Requake for a scientific paper, please cite it as:

Satriano, C. (2024). Requake: Repeating earthquakes search and analysis (X.Y). doi: 10.5281/ZENODO.10832204

Please replace X.Y with the Requake version number you used.

You can also cite the following abstract presented at the 2016 AGU Fall Meeting:

Satriano, C., Doucet, A. & Bouin, M.-P. (2021). Probing the creep rate along the Lesser Antilles Subduction Zone through repeating earthquakes. In AGU Fall Meeting Abstracts (Vol. 2021, pp. T25A-0167), bibcode: 2021AGUFM.T25A0167S