requake 0.8.3

Repeating earthquakes search and analysis

Requake

Repeating earthquakes search and analysis.

Copyright (c) 2021-2026 Claudio Satriano [e-mail]

Description

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.

Installation

Installing the latest release

Using Anaconda

The following command will automatically create an Anaconda environment named requake, install the required packages and install the latest version of SourceSpec via pip:

conda env create --file https://raw.githubusercontent.com/SeismicSource/requake/main/requake_conda_env.yml

If you want a different name for your environment, use:

conda env create -n YOUR_ENV_NAME --file https://raw.githubusercontent.com/SeismicSource/requake/main/requake_conda_env.yml

Activate the environment with:

conda activate requake

(or conda activate YOUR_ENV_NAME)

To keep Requake updated run the following command from within the environment:

pip install --upgrade requake

Or, to switch to a development snapshot, run:

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

Using pip and PyPI

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

You can install it easily through pip:

pip install requake

Installing a development snapshot

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.

Using pip

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.

Cloning the Requake GitHub repository

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 [e-mail]: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.

If you want the repository style rules to run locally before each commit, enable the included git hook once per clone:

scripts/setup_local_hooks.sh

You can also run the local style checks manually with:

scripts/check_style.sh

Running

Command line arguments

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

To get help, use:

requake -h

Different commands are available:

sample_config       write sample config file to current directory and exit
update_config       update an existing config file to the latest version
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.
build_templates     build waveform templates for one or more event
                    families
scan_templates      scan a continuous waveform stream using one or more
                    templates
wfcache             manage persistent waveform cache (prefetch, print,
                    inspect, extract, reset_failures)

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

Requake supports command line tab completion for commands and arguments, thanks to argcomplete. To enable command line tab completion run:

activate-global-python-argcomplete

(This is a one-time command that needs to be run only once).

Or, alternatively, add the following line to your .bashrc or .zshrc:

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

Typical workflow

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

When relying on FDSN web services for waveform data, it is strongly recommended to prefetch all waveform windows before running the scan. This downloads every required waveform once and stores it in a local SQLite cache, avoiding repeated downloads and dramatically reducing overall runtime for large catalogs:

requake wfcache prefetch

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

requake build_families

Performances

• requake scan_catalog is designed to fully utilize available CPU cores by processing earthquake pairs in parallel. On an M2 MacBook Air, scanning 95,034 earthquake pairs downloaded via FDSNWS took approximately 5 minutes using 7 worker processes, yielding ~19,000 pairs per minute. When repeating the same scan with a fully cached set of waveforms, runtime dropped to 84 seconds (~68,000 pairs per minute). These results indicate that overall performance is typically dominated by waveform download latency rather than computation.

• For large FDSN-based runs, use requake wfcache prefetch before requake scan_catalog to download all waveforms upfront into a local SQLite cache. This eliminates repeated downloads, lets the scan read exclusively from disk, and is the single most effective way to speed up catalog scanning.

• requake build_families is fast™.

How to Cite

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

Satriano, C. (2026). Requake: Repeating earthquakes search and analysis (X.Y). doi: 10.5281/ZENODO.10832203

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

You can also cite the following abstract presented at the 2021 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