EarthScope Data

USArray Data at the DMC

The USArray component of the EarthScope experiment is a continental-scale seismic observatory designed to provide a foundation for integrated studies of continental lithosphere and deep Earth structure over a wide range of scales. USArray will provide new insight and new data to address fundamental questions in earthquake physics, volcanic processes, core-mantle interactions, active deformation and tectonics, continental structure and evolution, geodynamics, and crustal fluids (magmatic, hydrothermal, and meteoric). Learn more about the project at usarray.org

Quick links:

USArray Data Overview

The IRIS DMC is the final archive and distribution point for all raw USArray data from each sub-component: Transportable Array, Reference Network (Backbone/Permanent Array), Flexible Array and Magnetotelluric Array.

The DMC's Virtual Network concept can be used to select various components of USArray data. The following table illustrates the scope of the USArray virtual networks:

Virtual Network code Description
_US-TA USArray Transportable Array stations
_US-REF USArray Reference Network (including Backbone/Permanent Array) stations
_US-FA USArray Flexible Array stations
_US-MT USArray Magnetotelluric stations
_US-ALL All USArray stations

USArray Transportable Array

The Transportable Array is a set of 400 broadband stations that will, over the 10 year course of the project, traverse the conterminous United States. The DMC receives 40 and 1 samples/second seismic data streams from each site in addition to related state-of-health data in real-time. Since mid-2010, atmospheric sensors have been installed at the TA stations. Information about these sensors is available at usarray.org Atmospheric.

Station lists:

List Description
Operating Stations List List of Operating TA stations in HTML format
Operating Stations: XML, Text, MS-Excel List of Operating TA stations in XML, Text (tab separated) and MS-Excel
All Stations List List of all (past, present and future) TA stations in HTML format
All Stations: XML, Text, MS-Excel List of all TA stations in XML, Text (tab separated values) and MS-Excel

Station maps:

Map Data Description
Operating Stations Google Map Operating TA stations as a web-viewable Google Map
Operating Stations KML Operating TA stations as a KML NetworkLink (e.g. for Google Earth)
Operating Stations Map Operating TA stations web page
All Stations Google Map All TA stations (past, present & future) as web-viewable Google Map)
All Stations KML All TA stations as a KML NetworkLink (e.g. for Google Earth)

Station reports:

Report Description
Station Digests Summary of station information, created after station closure
Landowner Reports Summary of station information, intended for the station hosts

USArray Reference Network (including Backbone/Permanent Array)

The Reference Network is composed of permanent stations at a roughly 300 km spacing across the United States and includes the 39 EarthScope-funded Permanent Array stations. The DMC receives 40 and 1 samples/second seismic data streams from most sites.


Station lists:

List Description
Station List List of Reference Network stations in HTML format
Stations: XML, Text, MS-Excel Reference Network stations in XML, Text (tab separated values) and MS-Excel

Station maps:

Map Data Description
Station Google Map Permanent Array stations as web-viewable Google Map
Station KML Reference Network stations as a KML NetworkLink (e.g. for Google Earth)
Station Map GIF Reference Network stations as a GIF image file, conterminous US only

USArray Flexible Array

The Flexible Array is a set of broadband and active-source oriented instruments deployed on a temporary basis according to individual proposal (the PASSCAL model). Data rates and availability from Flexible Array deployments depend on the individual proposals.

Station lists:

List Description
Station List List of Flexible Array stations in HTML format
Stations: XML, Text, MS-Excel Flexible Array stations in XML, Text (tab separated values) and MS-Excel

Station maps:

Map Data Description
Station Google Map Flexible Array stations as web-viewable Google Map
Station KML Flexible Array stations as a KML NetworkLink (e.g. for Google Earth)
Station Map GIF Flexible Array stations as a GIF image file

USArray Magnetotelluric

The magnetotelluric (MT) component of USArray consists of 7 permanent MT stations and a mobile array of 20 MT stations that will each be deployed for a period of about one month in regions of identified interest with a spacing of approximately 70 km.

Station lists:

List Description
Station List List of Magnetotelluric stations in HTML format
Stations: XML, Text, MS-Excel Magnetotelluric stations in XML, Text (tab separated values) and MS-Excel

Station maps:

Map Data Description
Station Google Map Magnetotelluric stations as web-viewable Google Map
Station KML Magnetotelluric stations as a KML NetworkLink (e.g. for Google Earth)
Station Map GIF Magnetotelluric stations as a GIF image file

All USArray Stations

Station lists:

List Description
Operating Stations List List of Operating USArray stations in HTML format
Operating Stations: XML, Text, MS-Excel List of Operating USArray stations in XML, Text (tab separated) and MS-Excel
All Stations List List of all (past, present and future) USArray stations in HTML format
All Stations: XML, Text, MS-Excel List of all USArray stations in XML, Text (tab separated values) and MS-Excel

Station maps:

Map Data Description
Operating Stations Google Map Operating USArray stations as a web-viewable Google Map
Operating Stations KML Operating USArray stations as a KML NetworkLink (e.g. for Google Earth)
Operating Stations Map Operating USArray stations as a webpage, conterminous US only
All Stations Google Map All USArray stations (past, present & future) as web-viewable Google Map)
All Stations KML All USArray stations as a KML NetworkLink (e.g. for Google Earth)

USArray Quality Control at the DMC

The DMC performs both automated and manual quality control on USArray data. A small team of analysts review raw USArray data regularly in addition to performing higher level quality control measurements. More details are available on the USArray Quality Control Overview page.

To Request USArray Data from the DMC

All USArray data at the DMC is managed within the existing DMC infrastructure along with all the other, non-USArray data at the DMC. This means that USArray data is available via all the DMC's traditional request mechanisms.

Before requesting data for the first time, we recommend that you learn about requesting and using IRIS data in general. A good place to start is at IRIS DMC Data Access and IRIS DMC Data Mousepad.

Real-time data: IRIS distributes near-real time miniSEED data directly from our real-time collection system (BUD). Click here for details about getting data from our real-time systems. The recommended method for receiving real-time data feeds is with the DMC's SeedLink service.

Transportable Array and Reference Network: Data from both the Transportable Array and Reference Network are delivered to the DMC in near-real time in SEED format. It is available via all the DMC's traditional request mechanisms including near-real time. Approximately 7 days after arriving at the DMC the data are copied to the primary archive making them available to all request mechanisms. The data remain in, and are available via, the real-time collection system (BUD) for two months.

Transportable Array SEED data qualities (in order of increasing preference):

SEED Quality Description
R Data delivered to the IRIS DMC via real-time telemetry.
D Gap-fill data delivered after real-time data, usually delivered within 3 months of real time.
Q TA final station data sets delivered after station removal, these data are primarily onsite (Baler) data merged with real-time telemetered data.

Transportable Array data do not contain routine timing or other corrections, the differences in the data qualities is primarily completeness and, in the case of TA Final data sets, richness in terms of included data quality bits in the Mini-SEED headers.

Most DMC request mechanisms will default to returning the highest quality data, or a mix thereof, available for the request. Some request mechanisms also allow selection of specific qualities.

Transportable Array Channel Descriptions

The following is a list of all channels collected for the Transportable Array. Not all of these channels are available in real-time, and not all channels are available for every station.

[sps — samples per second]

Channel Description Sample Rate (sps)
BHZ Broadband Seismometer Vertical ground velocity, Q330 Chan1 40
BHN Broadband Seismometer North ground velocity, Q330 Chan2 40
BHE Broadband Seismometer East ground velocity, Q330 Chan3 40
LHZ Broadband Seismometer Vertical ground velocity, Q330 Chan1 1
LHN Broadband Seismometer North ground velocity, Q330 Chan2 1
LHE Broadband Seismometer East ground velocity, Q330 Chan3 1
VHZ from LHZ via VLP389, gain=1 0.1
VHN from LHN via VLP389, gain=1 0.1
VHE from LHE via VLP389, gain=1 0.1
UHZ from VHZ via ULP379, gain=1 0.01
UHN from VHN via ULP379, gain=1 0.01
UHE from VHE via ULP379, gain=1 0.01
VEP input voltage, 1count=150mV 0.1
VEC system current, 1 count=1mA 0.1
VEA GPS antenna current, 1 count=1mA 0.1
VKI 330 internal temp, 1 count=1 degree C 0.1
VCO 330 voltage controlled oscillator 0.1
VM1 Boom position ch1, 1 count=0.1V 0.1
VM2 Boom position ch2, 1 count=0.1V 0.1
VM3 Boom position ch3, 1 count=0.1V 0.1
LCQ clock quality, in percent. See definition in Q330 MSEED description. 1
LCE clock phase error from UTC in usec 1
VFP percent of free packets in the DP4 queue 0.1
LTW a byte of status bit information related to onsite conditions 1
VCE from LCE via VLP389 0.1
VCQ from LCQ via VLP389 0.1
VTW from LTW via VLP389 0.1
ACE Administrative Clock Error, a blog of clock messages none
LOG a text log of datalogger and baler messages none
OCF a daily binary snapshot of the q330 configuration none
EP-LDM absolute barometric pressure in hPa, MEMS sensor QEP onboard, Q330 1
EP-LKM internal temperature inside VIE enclosure in degrees C, QEP onboard, Q330 1
EP-LIM internal humidity inside VIE enclosure in percent, QEP onboard, Q330 1
EP-LEP voltage supply, in volts, QEP onboard, Q330 1
EP-LCE clock phase error relative to UTC, in usec, QEP onboard, Q330 1
EP-LCO oscillator control value, QEP onboard, Q330 1
EP-BDO absolute barometric pressure Setra 278 w/o 800 hPa offset, QEP ADC3 Chan1 Q330 40
EP-LDO absolute barometric pressure Setra 278 w/o 800 hPa offset, QEP ADC3 Chan1 Q330 1
EP-BDF infrasound microphone, relative barometric pressure,NCPA IFS-4532, QEP ADC3 Chan2, Q330 40
EP-LDF infrasound microphone, relative barometric pressure,NCPA IFS-4532, QEP ADC3 Chan2, Q330 1

Additional channels for a Strong Motion sensor (Kinemetrics EST Episensor, 2g, 10V/g)

Channel Description Sample Rate
HNZ Accelerometer, vertical ground acceleration, Chan 4 Q330 100 sps
HNN Accelerometer, north ground acceleration, Chan 5 Q330 100
HNE Accelerometer, east ground acceleration, Chan 6 Q330 100
LNZ Accelerometer, vertical ground acceleration, Chan 4 Q330 1
LNN Accelerometer, north ground acceleration, Chan 5 Q330 1
LNE Accelerometer, east ground acceleration, Chan 6 Q330 1

Additional channels for a Vaisala WXT-520 weather station

Channel Description Sample Rate
EP-LWD Wind Direction in degrees, Vaisala WXT520, QEP Q330 1 sps
EP-LWS Wind Speed in 0.1 m/sec, Vaisala WXT520, QEP Q330 1
EP-LDV Outdoor Pressure in 0.1 hPA, Vaisala WXT520, QEP Q330 1
EP-LKO Outdoor Temperature in 0.1 deg C, Vaisala WXT520, QEP Q330 1
EP-LIO Outdoor Humidity in 0.1 percent, Vaisala WXT520, QEP Q330 1
EP-LRO Rain Intensity in 0.1 mm/hour, Vaisala WXT520, QEP Q330 1
EP-LRH Hail Intensity in hits/cm**2*hour, Vaisala WXT520, QEP Q330 1
EP-LKH Heater Temperature in 0.1 deg C, Vaisala WXT520, QEP Q330 1
EP-LEH Heater Voltage in 0.1 V, Vaisala WXT520, QEP Q330 1
EP-LEW Supply Voltage in 0.1 V, Vaisala WXT520, QEP Q330 1
EP-LER Reference Voltage in 0.001 V, Vaisala WXT520, QEP Q330 1

Flexible Array

Flexible Array experiments are usually conducted like traditional IRIS PASSCAL experiments in that data is retrieved from the field at specific intervals, sent to the PASSCAL Instrument Center and finally shipped to the DMC. These data are available via all the DMC's traditional request mechanisms shortly after being received at the DMC with the access method dependent on the data type (either the SEED archive or Assembled data sets).

In some cases Flexible Array experiment data are telemetered in near-real time to the DMC in which case the data is managed similarly to Transportable Array, Reference Network or other real-time data feeds.

USArray Data Access Examples

This section is not intended to be an exhaustive tutorial for DMC data access, that function is served by the IRIS DMC Data Access Tutorial. Instead the purpose of these examples are to provide a brief illustration of and kickstart for data access.

Real-time data feeds

The preferred method to get continuous, real-time data feeds from USArray stations is to use the IRIS DMC's SeedLink service. Note that most but not all USArray stations are delivered to the DMC in real-time.

SeedLink client software exists for Antelope, Earthworm, SeisComP and a command line client, slarchive, that will write Mini-SEED data directly into the directories and files of your chosing. In the case of Antelope and Earthworm, client programs are included with the recent releases, otherwise source code for client software can be found on the SeedLink service overview page.

BREQ_FAST

breq_fast is an email-based request mechanism. A user sends a formatted request to breq_fast at iris.washington.edu, after which the user is notified by email when the request is ready to download from the DMC. The breqfast format is described here.

As a simple example, requesting a 40-minute window of data from the LHZ channel of every TA network station could be done by sending the following in the body of an email to breq_fast at iris.washington.edu:

.NAME Joe Researcher
.EMAIL joe@university.edu
.MEDIA FTP
.LABEL TA-TongaEvent
.END
* TA 2006 05 03 15 30 00.0 2006 05 03 16 10 00.0 1 LHZ

Note that this request only includes the "TA" network stations (the stations installed by IRIS specifially for the Transporable Array). To request data from all Transportable Array stations including the shared and cooperative stations replace the "TA" network code with the "_US-TA" virtual network code.


Web Services

IRIS web services provides direct access to data and metadata archived at the DMC.

Sample queries:

http://service.iris.edu/fdsnws/station/1/query?net=TA&startafter=2013-01-01&output=text

http://service.iris.edu/irisws/timeseries/1/query?network=TA&station=Z55A&location=--&channel=BHZ&starttime=2013-03-10T22:30:00&endtime=2013-03-11T02:00:00&bpfilter=0.01-0.1&output=plot