Network Outage


Starting around 2017-02-17 16:20 UTC (11:20 EDT / 8:20 PDT) IRIS Data Services experienced a network outage. We are still looking into the cause of the outage and hope to be back online as soon as possible. We apologize for the inconvenience to your workflow.

Software Downloads – SAC v. 101.6a


The IRIS DMC distributes the Seismic Analysis Code (SAC) software for scientists conducting research using IRIS data. You must register with an online form to receive the SAC software.

SAC Version 101.6 introduced several new features including a new command parser that simplifies coding, improved precision for blackboard variables, colored fill for positive and negative portions of seismograms, and corrections of many errors and warnings.

Version 101.6a fixes bugs in v101.6 and adds a single-file PDF version of the SAC manual. Details can be seen from the detailed HISTORY of modifications files and brief overview of major CHANGES posted in the SAC project pages on SeisCode.


SAC (Seismic Analysis Code) is a general purpose interactive program designed for the study of sequential signals, especially time series data. Emphasis has been placed on analysis tools used by research seismologists in the detailed study of seismic events. Analysis capabilities include general arithmetic operations, Fourier transforms, three spectral estimation techniques, IIR and FIR filtering, signal stacking, decimation, interpolation, correlation, and seismic phase picking. SAC also contains an extensive graphics capability. Binary distributions are available for current (2013) Mac OSX and Linux operating systems. Other platforms or operating systems must be built from the source code.

The Seismic Analysis Code: A Primer and User’s Guide by George Helffrich, James Wookey and Ian Bastow has just been published by Cambridge University Press. View the publisher’s page »

Successful builds for v101.6a have been made and tested on PC/Cygwin, Sun/Oracle Solaris and Older Linux and Mac releases.

SAC 101.5 Distribution Statistics
Accounting of source and binary downloads from IRIS for SAC v101.5c. For v101.6a, as for v101.6, binaries are provided only for 64-bit Mac and 64-bit Linux.

Please note: The Seismic Analysis Code software is available to IRIS Members and Affiliates. As of October 2006, IRIS may also distribute the SAC software to collaborators such as the U.S. Geological Survey, Air Force Technical Applications Center, members of the International Federation of Digital Seismograph Networks and other non-U.S. seismological institutes who are involved in relevant research projects with IRIS. However, IRIS will not distribute the SAC software to any country on the embargoed list of the U.S. Department of Commerce.


Plotting and Display , Processing Programs

External Developers

  • Brian Savage, University of Rhode Island (URI)
  • Arthur Snoke, Department of Geosciences at Virginia Tech (VT)