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This is a subset of our downloadable software for earthquake research. USGS uses GitHub for all new software development, as well as open sourcing older software as time allows. For a comprehensive listing of all available software, see how our applications work, and to collaborate with us, please go to USGS GitHub.

Filter Total Items: 37


The Product Distribution Layer (PDL) is a USGS platform for receiving earthquake data over the Internet in near-real time.

P-Phase Picker

PPHASEPICKER is a powerful tool for automatically picking P-phase onsets with high precision without requiring detection interval or threshold settings.


HypoDD is a Fortran computer program package for relocating earthquakes with the double-difference (DD) algorithm of Waldhauser and Ellsworth (2000).

HASH 1.2

HASH is a Fortran 77 code that computes double-couple earthquake focal mechanisms from P-wave first motion polarity observations, and optionally S/P amplitude ratios.

HYPOINVERSE Earthquake Location

HYPOINVERSE2000 determines earthquake locations and magnitudes from seismic network data like first-arrival P and S arrival times, amplitudes and coda durations.

Coulomb 3

Coulomb is designed to investigate Coulomb stress changes on mapped faults and earthquake nodal planes, and is intended both for publication-directed research and for university teaching and instruction.

ComCat Wrapper Libraries

Bulk access via scripts, programs, and tools for obtaining specific products from ComCat (the earthquake catalog).

Direct Green's Function Synthetic Seismograms

These programs are an implementation of the Direct Green’s Function method described by Friederich and Dalkolmo (1995) and Dalkolmo (1993).


est_noise is a time-series analysis program that allows the user to fit various, standard functions to their data (rates, offsets, rate-changes, sinusoidals, exponentials, and/or user-defined functions) and simultaneously quantifies the amount of temporal correlation in the time-series data.


FPFIT is a Fortran program that computes double-couple fault plane solutions from P-wave first motion data using a grid search method.


Cleanstrain+ is a program to process strainmeter data.


CLUSTER2000 recognizes clusters in space-time in an earthquake catalog.