The Quality Assurance (QA) team at the IRIS DMC is tasked with monitoring the quality of the IRIS DMC seismic data archive and providing resources relating to data quality to the earth science community. On this page you will find information on general QA practices, MUSTANG metrics and PDFs, and links to QA related products and services at the DMC.
QA Related Web Services, Products, and Software
Web Services and Client Tools
MUSTANG, Modular Utility for Statistical Knowledge Gathering: seismic data quality metrics and Probability Density Functions (PDFs).
- Introduction to MUSTANG
- MUSTANG Databrowser , a web based MUSTANG metrics plotting tool
- LASSO , a web based station performance tool utilizing MUSTANG metrics
- MUSTANGular , an interactive map viewer of station metrics
Global ShakeMovie synthetics at the DMC
Global ShakeMovie synthetics at the DMC event listing
R Package on CRAN, IRISMustangMetrics is the official public release of R code used by MUSTANG to calculate metrics.
ISPAQ, software for calculating MUSTANG-style seismic data quality metrics on a local machine.
PQLX, open-source software seismic trace and PDF viewer.
Data Problem Reports – search submitted data problem reports by station and network. This is not an exhaustive listing of all data problems that may exist in the archive.
- (2020-06-23) We are pleased to announce the addition of three new metrics to MUSTANG: max_range, sample_rate_channel, and sample_rate_resp. We are now computing these metrics for incoming data and have begun the process of calculating values back through the data archive. Full descriptions of these metrics can be found at these links:
max_range: calculates the difference between the largest and smallest sample value in a 5 minute rolling window and returns the largest value encountered within a 24-hour timespan.
sample_rate_channel: A boolean measurement that returns 0 if miniSEED and channel sample rates agree within 1%, or 1 if they disagree.
sample_rate_resp: A boolean measurement that returns 0 if miniSEED and response-derived sample rates agree within 15%, or 1 if they disagrees.
- (2020-04-09) MUSTANG metrics are now available for data in the IRIS PH5-format archive for active source and nodal experiments. See the IRIS Data Services Spring 2020 Newsletter article MUSTANG Metrics for PH5-format Data at the IRIS DMC.
- (2020-01-14) We have released a new MUSTANG Databrowser (http://ds.iris.edu/mustang/databrowser) version that has the following improvements:
1. The drop down network-station-location-channel lists now include experiments stored in our PH5-format archive. We have good metric measurement coverage for PH5 experiments from 2017-2019 and we are working backwards in time to calculate metrics for experiments from 2005-2016.
2. The “gap duration” plot type now has a fourth plot added. The plots included in this view are: gap duration vs. date, gap duration vs. time of day, a histogram of gap durations, and number of gaps vs. time.
3. The PDF noise mode spectrogram plot now has the same default color scale limits (plot.powerscale.autorange=0.9) as the spectrogram web service (http://service.iris.edu/mustang/noise-spectrogram/).
- (2019-12-12) A pdf of our AGU poster entitled “Data Quality Assurance at the IRIS DMC: Expanding and Improving the MUSTANG System” is available at: https://www.essoar.org/doi/abs/10.1002/essoar.10501324.1
Citations and DOIs
To cite the MUSTANG system or reference the use of MUSTANG metrics:
- Assuring the Quality of IRIS Data with MUSTANG
Robert Casey, Mary E. Templeton, Gillian Sharer, Laura Keyson, Bruce R. Weertman, Tim Ahern
Seismological Research Letters (2018) 89 (2A): 630-639.
There is a Message Center List available to provide a forum for QA discussion by the community (subscription required):
And a Message Center List for MUSTANG-related announcements (including service outages and downtimes, etc.):
Issues regarding Quality Assurance at the IRIS DMC can be addressed to this Message Center List :
IRIS DMC QA Staff can be contacted directly at:
Frequently Answered Questions
There are currently 5 Quality Assurance related questions:
- How accurate are the USArray Transportable Array instrument orientations?
- Why does the data I downloaded from a USArray TA station look crazy?
- Someone told me the USArray TA data has gaps. Is that true?
- Does IRIS perform quality assurance on the data it receives?
- What does the M, D, R, or Q character mean in my data file name?
There are currently 4 Quality Assurance tutorials: