SWEEP: a utility for seismic waveform discovery, extraction and processing

What it does

• Search + fetch + process seismic waveforms from online repositories
• Anywhere on Earth* for any time period and search radius
• Prepare and QA waveforms for various analyses, in particular earthquake source estimation

(*NEXT: Earth's Moon and Mars)

How it works

0. check for earthquakes automatically* or enter earthquake information manually
1. fetch all possible waveform data across open networks (and some closed networks)
2. Perform various checks on the data and prepare the waveforms for analysis

(*Using a built-in utility, or coupling with an external one)

Installation

git clone [email protected]:celsoa/sweep.git

Usage

cd sweep
python run_sweep.py <inputfile>

• This command will extract the waveforms for the geographic location and time listed in inputfile
• When the script finishes, it will save the waveforms in a folder with the same name as the time listed in inputfile
• For example, if the time is 2000-12-24T23:59:00 the output folder will be named 20001224235900

Waveform corrections, QA checks, summary reports

• correct for instrument response
• demean, detrend (linear, quadratic, etc)
• resample
• pre- and post-filter waveforms (causal, acausal, lowpass, highpass, etc)
• interpolate missing data
• rescale waveform amplitudes (mm, cm, m, etc)
• various status/summary/QA reports: waveform quality, SNR, spectrograms, instrument response, station map, station .xml file

Waveform processing for earthquake analysis

• rotate to source-receiver frame (RTZ) using sensor orientations
• rotate to UVW triaxial orthogonal frame of the T120PH Nanometrics sensor (useful for isolating spurious signals to sensor components)
• add null traces so that there are always 3 components (required when rotating)
• access embargoed data sets (requires user name and password)
• write SAC files with headers
• interface with other databases (see below)

Interface with various data centers and databases

Open data centers

• IRIS
• EIDA
• NORSAR
• Raspberry Shake

Restricted data centers or embargoed datasets (usually require a password)

• IMS
• ?

The LLNL database of nuclear explosion and earthquake waveforms

• An assembled western United States dataset for regional seismic analysis ISSO 9660 CD, LLNL release UCRL-MI-222502, W. Walter et al. (2006)
• The database can be downloaded from IRIS DMC at https://ds.iris.edu/mda/18-001
• The package needed to access these waveforms is here: https://github.com/krischer/llnl_db_client
• Follow the install instructions, then set a symbolic link as ln -s /PATH_TO_LLNL_CLIENT/llnl_db_client .