Software to Download

3D focal mechanisms

Authors:	Keith A. Labay and Peter J. Haeussler
Usage:	View earthquake focal mechanism symbols three dimensionally
Platform:	Windows
Interface:	ArcScene® 9.x
Input:	A GIS point dataset of earthquake locations containing strike, dip, and rake values for a nodal plane of each earthquake
Examples:	Available at website
Manual:	Available at website
Download:	See online documentation

3D Focal Mechanisms is a tool for viewing earthquake focal mechanism symbols three dimensionally. This tool operates within the Environmental Systems Research Institute (ESRI®) GIS software ArcScene® 9.x. The program requires as input a GIS point dataset of earthquake locations containing strike, dip, and rake values for a nodal plane of each earthquake. Other information, such as depth and magnitude of the earthquake, may also be included in the dataset. By default for each focal point, 3DFM will create a black and white sphere or “beach ball” that is oriented based on the strike, dip, and rake values. If depth values for each earthquake are included, the focal symbol will also be placed at its appropriate location beneath the Earth's surface.

3D velocity modeling

Authors:	Cliff Thurber (most recently modified by Donna Eberhart-Phillips)
Platform:	Unix
Other:	arc2cnv.c C code to convert phase data from hypoinverse archive format
Download:	simulps12.for (197k), simin.tar.Z (79k)

simulps12.for: Fortran code (VMS compatible) for 3-D velocity model determination and hypocentral location with local earthquake data. Full inversion, not tomography, this is the program written by Cliff Thurber and modified by others (most recently Donna Eberhart-Phillips).

simin.tar.Z: Example input files for simulps12.for, including the VMS command file. These don't form a complete set that go together, but do show all the different types of input files. This a Unix tar compressed with the Unix compress command.

cleanstrain+

Author:	John Langbein
Usage:	Analyze strainmeter data in order to estimate tidal coefficients and pressure admittance
Platform:	Unix and/or Mac OS X (Requires Fortran compiler for Mac OS X)
Interface:	Command line
Input:	Time series of strainmeter data
Output:	Cleaned-up strainmeter data
Docs:	Online documentation: installation, manual, examples
Download:	cleanstrain+

Cleanstrain+ is a program to process strainmeter data. This code will simultaneously estimate the tidal constituents, pressure admittance, offsets, rate changes, and other terms using least-squares but, importantly, incorporating the temporally correlated nature of strain data (that is, the power spectra is red).

CLUSTER2000

Author:	Paul Reasenberg
Usage:	Identify clusters (e.g., aftershocks) in an earthquake catalog
Platform:	Unix, or any platform with Fortran
Interface:	Parameters read from standard input
Input:	Catalog text file
Output:	Several text files
Docs:	Comments in source code
Download:	Fortran source code (35k), Makefile (233b)

CLUSTER2000 recognizes clusters in space-time in an earthquake catalog. It is intended for use in removing aftershocks or "declustering" the catalog. The methods used are described in "Second-Order Moment of Central California Seismicity, 1969-1982" (P. Reasenberg, JGR v.90., pp.5479-5495, 1985). The current version (CLUSTER2000x) reads catalogs in a variety of standard formats. However, it is not fully Y2000 compatible. While it reads the Y2K formats for HYPOINVERSE and HYPO71, CLUSTER2000x requires all data to belong to one century.

Coulomb 3

Authors:	Shinji Toda, Ross Stein, Jian Lin, Volkan Sevilgen
Usage:	Stress-triggering software
Platform:	Matlab on Windows, Mac or Unix
Interface:	Menu driven
Output:	Grahics and text
Manual:	Online documentaiton
Download:	See online documentation

Coulomb 3 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.

One can calculate static displacements (on any surface or at GPS stations), strains, and stresses caused by fault slip, magmatic intrusion or dike expansion. Problems such as how an earthquake promotes or inhibits failure on nearby faults, or how fault slip or dike expansion will compress a nearby magma chamber, are germane to Coulomb. Geologic deformation associated with strike-slip faults, normal faults, or fault-bend folds is also a useful application. Calculations are made in an elastic halfspace with uniform isotropic elastic properties following Okada [1992].

We believe that one learns best when one can see the most and can explore alternatives quickly. So the principal feature of Coulomb is ease of input, rapid interactive modification, and intuitive visualization of the results. The program has menus, sub-menus, check-items, and dialogue boxes to ease operation. The internal graphics are suitable for publication, and can be easily imported into illustration or animation programs for further enhancements.

Direct Green's Function Synthetic Seismograms

Author:	Fred Pollitz
Usage:	Calculate synthetic seismograms on a radially stratified model
Platform:	Unix, Fortran source codes
Input:	Elastic parameters, density, Qp and Qs structure, finite fault parameters
Output:	Synthetic seismograms at Earth's surface or specified depth
Examples:	Contained in downloadable file
Download:	DGRFN.tar (1.6 MB)

These programs are an implementation of the Direct Green’s Function method described by Friederich and Dalkolmo (1995) and Dalkolmo (1993). They solve the seismic wave equation in a spherically layered isotropic medium using a decomposition into spheroidal and toroidal motions. For each spherical harmonic degree l and azimuthal order number m, the (l,m) response function is deternined subject to jumps in the displacement-stress vector at the source radius, a zero-traction boundary condition at Earth’s surface, and a homogeneous isotropic elastic solid at the base of the specified Earth model. The computation of synthetics is stable at both high and low frequencies, as well as at high and low spherical harmonic degrees.

Earthquake Directivity Model

Author:	Paul Spudich
Usage:	Calculate seismic directivity
Platform:	Any platform running MATLAB
Interface:	MATLAB command line
Input:	Function calling arguments
Output:	.txt and .mat files
Examples:	Contained in downloadable file
Download:	See online documentation

Isodirect1 is a MATLAB-language function for modeling seismic directivity at user-selected sites around a user-defined fault. Isodirect1.m implements the Spudich and Chiou (Earthquake Spectra, 2008) directivity model. The results of isodirect1.m should be combined with the ground motion predictions of a non-directive predictive model like any of the four NGA models. Input to isodirect1.m consists of the coordinates of a set of sites where directivity predictions are desired, the coordinates of the corners of one or more fault segments, hypocenter location, earthquake magnitude and slip rake, desired periods for output. Output consists of directivity amplifications for all input sites, plus many intermediate results, such as the points on the fault closest to the input sites, rupture distances, etc.

Earthquake Information Distribution System (EIDS)

Contacts:	Jeremy Fee and Dave Oppenheimer
Usage:	Distribution of earthquake data over the Internet
Platform:	Any O/S that supports Java
Interface:	Runs in background
Output:	Files containing information about earthquakes
Download:	See online documentation

The Earthquake Information Distribution System (EIDS) provides a method for receiving earthquake data over the Internet in near-real time. EIDS replaces the Quake Data Distribution System (QDDS) and provides either CUBE or EQXML formatted output messages.

FPFIT, FPPLOT and FPPAGE

Authors:	Paul Reasenberg and David Oppenheimer
Usage:	Calculate and plotfault-plane solutions from first-motion data
Platform:	Unix
Interface:	Command line
Output:	Grahics and text
Examples:	Included in dowload file
Manual:	Online documentation and USGS Open-File report
Tutorial:	Included in dowload file
Download:	fpfit_source.tar (1.3 MB)

FPFIT is a Fortran program that computes double-couple fault plane solutions from P-wave first motion data using a grid search method. The companion programs FPPLOT and FPPAGE plot the results on stereo nets for interactive viewing or for printing. There are additional programs in the package to create summary tables and to plot P&T axes for suites of mechanisms on stereo nets.

Ground Motion Parameter Calculator

Author:	E.V. Leyendecker, Arthur Frankel, Kenneth Rukstales, Eric Martinez, Nicolas Luco, Jeremy Fee, Ned Field, Nitin Gupta, Vipin Gupta
Usage:	Calculate estimated ground motions for building design
Platform:	Any O/S that supports Java
Interface:	Java Graphic User Interface (GUI)
Output:	Images and Text
Download:	See online documentation

Hazard curves, uniform hazard response spectra, and design parameters are available for sites in the 50 states of the United States, Puerto Rico and the U.S. Virgin Islands. Additionally, design parameters are available for Guam and American Samoa.

HASH 1.2

Authors:	Jeanne Hardebeck and Peter Shearer
Usage:	Calculates earthquake focal mechanisms
Platform:	Unix
Interface:	Command line / text input files
Output:	Text files
Examples:	Included in download file
Manual:	PDF included in download file
Download:	hash.v1.2.tar.gz (1 MB)

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. HASH is designed to produce stable high-quality focal mechanisms, and tests the solution sensitivity to possible errors in the first-motion input and the computed take-off angles. The technique is described by Hardebeck and Shearer (BSSA 92, pp. 2264-2276, 2002.) Examples are provided for data in FPFIT input format. The code is designed to be as input-format independent as possible, so only minor editing is needed to use data in other formats.

hypoDD

Author:	Felix Waldhauser
Maintenance:	Felix Waldhauser, Bruce Julian, Bill Ellsworth, Keith Richards-Dinger
Usage:	Implements the double-difference earthquake location algorithm
Platform:	Unix
Interface:	Command line / text input files
Output:	Text files
Examples:	Examples, More examples
Manual:	PDF and PostScript files in tar file
Download:	HYPODD_1.0.tar.gz (14 MB)

HypoDD is a Fortran computer program package for relocating earthquakes with the double-difference (DD) algorithm of Waldhauser and Ellsworth (2000). The DD technique takes advantage of the fact that if the hypocentral separation between two earthquakes is small compared to the event-station distance and the scale length of velocity heterogeneity, then the ray paths between the source region and a common station are similar along almost the entire ray path (Frechet, 1985; Got et al., 1994).

HYPOINVERSE Earthquake Location

Author:	Fred Klein
Usage:	Locate earthquakes and determine magnitudes in a local or regional seismic network
Platform:	Unix or Vax, Fortran source code
Interface:	Command line, files or keyboard
Input:	ASCII text
Output:	ASCII text
Examples:	Sample runs in distribution directory
Manual:	Extensive open-file document, in Microsoft Word and postscript formats
Tutorial:	Simple examples included in manual
Download:	version 1.3 (2.2 MB) version 1.2 (2 MB)

HYPOINVERSE2000 determines earthquake locations and magnitudes from seismic network data like first-arrival P and S arrival times, amplitudes and coda durations. The present versions HYPOINVERSE2000 (version 1.2 or 1.3) are in routine use by many networks. Hypoinverse version 1.3 is the standard location program supplied with the Earthworm seismic acquisition and processing system (AQMS) and has thus gotten wide use. Crustal models can be multiple to cover different regions, and either flat layer or flat layer with linear velocity gradients. Version 1.3 also supports negative magnitudes, independent S models, and crustal models from the HYPOELLIPSE program, including layer models, gradient over halfspace models, depths relative to sea level, negative depths above sea level, and use of station elevations. It is Y2000 compatible.

LISS - Live Internet Seismic Server

Author:	Albuquerque Seismo Lab
Usage:	Access to GSN and ANSS realtime seismic waveform data.
Platform:	UNIX, PC, or any platform with C
Interface:	Command line and runs in background
Input:	mini-SEED file
Output:	screen image, files
Manual:	LISS Client Software Info
Download:	LISS Client Software

The Live Internet Seismic Server (LISS) is a data transmission protocol developed at the USGS Albuquerque Seismological Laboratory. It was initially used both to acquire data from remote seismic stations as well as to distribute data to users. Today, the LISS is primarily used to distribute data. It allows for near-real-time data flow from seismic stations around the world.

MacR1D

Author:	Jim Luetgert
Usage:	1-D travel time calculation
Platform:	Mac OS 9
Interface:	Menu driven
Output:	PICT file
Download:	MacR1D.zip

MacR1D is a one-dimensional seismic travel-time calculator for Macintosh. Travel-times vs distance are calculated for P and S arrivals (sorry, no converted phases or multiples) for sources at any depth. These may be compared to observed travel-times. This is a very quick way to define 1-d velocity models from observed arrival pics.

MacRay

Author:	Jim Luetgert
Usage:	General purpose 2-D seismic seismic ray tracer
Platform:	Mac OSX or PC
Interface:	Menu driven
Output:	PICT file
Examples:	Included in download file
Manual:	MS Word document included in download file
Download:	Mac OSX - MacRay_V2 (1.9 MB); PC - RAY84PC (1.2 MB)

MacRay is a general purpose two-dimensional seismic ray-tracer for Macintosh. Originally written to trace rays through 2-dimensional p-wave models, MacRay has grown to support 2-d models defined in Vp, Vs and density. In addition to being able to model the full range of simple to complex raypaths, the 2-d gravity response of the model may also be calculated. For surveys providing seismic P, S and converted wave arrivals in addition to gravity measurements, the full suite of physical properties may be modeled; Vp, Vs, density, Poisson's ratio, Vp/Vs, Shear modulus, Bulk modulus, Young's modulus, Lame's parameter, lithostatic pressure.

With the addition of an assumed or measured geothermal gradient, we can model the pressure and temperature conditions at any point in our earth model. A recent addition to MacRay allows you to define the features of a pressure-temperature diagram (e.g. metamorphic grade, solidus) and map those P-T regions back into the earth model.

The PC version is a port of Ray84 written for Vax. It was ported by Hans Thybo of Copenhagen University, Denmark.

OpenSHA

Authors:	Ned (Edward) Field (USGS/SCEC), Nitin Gupta (USC/SCEC), and Vipin Gupta (USC/SCEC)
Usage:	Open-source seismic hazard analysis
Platform:	Any O/S that supports Java
Manual:	See online documentation
Download:	See online documentation

OpenSHA is an effort to develop object-oriented, web- & GUI-enabled, open-source, and freely available code for conducting Seismic Hazard Analyses (SHA). Our goal is to provide a framework where any arbitrarily complex (e.g., physics based) earthquake-rupture forecast, ground-motion, or engineering-response model can "plug in" for analysis without having to change what’s being plugged into.

PQLX

Authors:	Dan McNamara, Richard Boaz
Usage:	Evaluate seismic station performance
Platform:	Unix
Interface:	GUI
Input:	standard seismic data formats
Output:	MySQL database, images, plots
Examples:	See sample data and response file
Download:	See online documentation

PQLX is open-source software system for evaluating seismic station performance and data quality. The software consists of a server and client but also includes data extraction and manipulation tools. Given waveform data and instrument response files, PQLX server calculates trace statistics, Power Spectral Densities (PSD), and Probability Density Functions (PDF) and writes the results to a MySQL database for quick access.

Probabilistic Seismic Hazard Calculation Software

Authors:	Art Frankel and Chuck Mueller
Usage:	Programs used to construct the 1996 National Seismic Hazard Maps
Platform:	Unix, Fortran source codes, some C subroutines
Interface:	command line
Download:	See online documentation

Computer codes used to construct the 1996 U.S. National Seismic Hazard Maps.

SATSI

Authors:	Jeanne Hardebeck and Andy Michael
Usage:	Spatially and/or temporally varying stress field from focal mechanisms
Platform:	Unix (or any platform with C)
Interface:	Command line / text input files
Output:	Text files
Examples:	Included in download file
Download:	SATSI.tar (360k)

SATSI (Spatial And Temporal Stress Inversion) is a modified version of Michael's (JGR 1984, 1987) code that inverts focal mechanism data for a spatially and/or temporally varying stress field. The inversion finds the least complex stress field model that is consistent with the data. It uses an adaptive smoothing method that discriminates between variations that are or aren't strongly required by the data and retains only variations that are well-resolved. The technique is described and validated in Hardebeck and Michael (JGR 111, B11310, doi:10.1029/2005JB004144, 2006.) The tar file contains C codes implementing the inversion method for 2D and 4D stress fields (1D and 3D fields can be treated as simplified cases), and example input data and Perl scripts.

ShakeCast “Lite” – ShakeMap RSS Reader

Authors:	Kuo-Wan Lin and David Wald
Usage:	Automated ShakeMap delivery to users, facilitating use of ShakeMap products and post-download post-commands (script startup)
Platform:	Unix, Windows
Interface:	Scripts / text configuration files
Output:	ShakeMap products and post-commands (Google Earth, Browser, etc.)
Examples:	Available at website
Manual:	Included in download file
Download:	See online documentation

Delivers maps of areas affected by an earthquake. Areas of interest can be defined, and shaking thresholds can be set to trigger automatic notifications. Easy to integrate with in-house systems.

Slick Package

Author:	Andy Michael
Usage:	Stress inversion from slip data
Platform:	Unix, PC (or any platform with C)
Interface:	Command line, can be run as batch mode
Bound Program:	Onnet, Stereonet plotting package
Output:	Text, graphics via onnet stereonet plotting program
Examples:	Included in download file
Manual:	ASCII Text and Postscript files in included in download file
Tutorial:	Included in download file
Download:	Unix - stress.tar.Z (41k); PC - stresspc.zip (160k)

The slick package uses fault slip data (either field observations or from focal mechamism) to find the stress tensor that best explains the observations. Inputs are the orientation and slip direction of a set of fault planes. Outputs are the oreintation and shape of the stress ellipsoid, including confidence regions, and statistics used to judge the success of the inversion. This method uses the linear inversion agorithm and non-parametric bootstrap statistics.

Unix: The code to invert fault slip data for the stress tensor. format is compressed tar. To extract on a Unix system use the command % zcat stress.tar.Z | tar xf - It will expand into a number of files in your current directory. You also need to get the onnet plotting package.

PC: Same as stress.tar.Z but containing Leigh House of Los Alamos' conversion of the software to PC compatibility. The zip was done with Zip 1.0 (29 September 1991).

Slope Performance During an Earthquake

Authors:	Randall W. Jibson and Matthew W. Jibson
Usage:	Using Newmark’s method and simplified decoupled analysis to model slope performance during earthquakes
Platform:	Any O/S that supports Java
Interface:	Java GUI
Manual:	Available in download file
Download:	See online documentation

This program package is designed to allow users to conduct Newmark sliding-block analysis and simplified decoupled analysis to estimate co-seismic slope displacements.

STATIC1D

Author:	Fred Pollitz
Usage:	Calculate static displacements and gravity change from earthquake faulting on a radially stratified model
Platform:	Unix, Fortran source codes
Input:	Elastic parameters, density, finite fault parameters
Output:	Displacements and gravity anomaly at Earth's surface or specified depth
Examples:	Contained in downloadable file
Download:	STATIC1D.tar.gz

These programs solve the equations of static equilibrium in a spherically layered isotropic medium using a decomposition into spheroidal and toroidal motions. For each spherical harmonic degree l and azimuthal order number m, the (l,m) response function is deternined subject to jumps in the displacement-stress vector at the source radius, a zero-traction boundary condition at Earth's surface, and a homogeneous isotropic elastic solid at the base of the specified Earth model. The programs are flexible, being suitable for calculations of the static displacement field at distances ranging from local to global.

strainz17: Earthquake strains and rotations

Author:	Paul Spudich
Usage:	Calculate strains and rotations of an array
Platform:	Any platform running MATLAB
Interface:	MATLAB command line
Input:	Seismograms from several stations, via function's calling arguments
Output:	.txt, .mat, and .pdf files
Examples:	Contained in downloadable file
Download:	See online documentation

Strainz17.m is a MATLAB-language function for deriving the best-fitting uniform strain tensor and rigid body rotation as functions of time, based on ground displacement or velocity recordings made on an array of sensors. Strainz17.m implements the theory in Spudich et al. (J. Geophys. Res., 1995) and Spudich and Fletcher (Bull. Seismol. Soc. Am., 2008). In addition to the strainz1717.m function, the downloadable file provides sample input and output data, and it provides functions for running the sample test cases.

VISCO1D

Author:	Fred Pollitz
Usage:	Calculate displacements/velocities and strain/strain rates
Platform:	Unix, Fortran source codes
Interface:	Command line
Input:	Viscoelastic model parameters, finite-fault source parameters
Output:	Viscoelastic-relaxation deformation fields at earth's surface or at depth
Manual:	1.3 MB .pdf file
Download:	2.1 MB .zip file

VISCO1D-v3 is a program package to calculate quasi-static deformation on a layered spherical Earth from a specified input source (fault plane parameters) at specified points on the surface or at depth.

It uses a spherical harmonic expansion of the global deformation field and evaluates a sum of viscoelastic normal modes in a semi-analytic computation.

Version 3 of VISCO1D-v3 is now available (updated on Jan. 29, 2007).