By integrating scientific information derived from its multi-disciplinary observatories, which use a wide variety of geophysical instrumentation, EarthScope's scientists are developing a comprehensive, time-dependent picture of the continent beyond that which any single discipline can achieve. Data obtained from these observatories allows scientist to describe how geological forces shaped North America's landscape and contribute to the public's understanding of our dynamic Earth. EarthScope's use of advanced instrumentation permits us to answer some of the outstanding questions in Earth Sciences by looking deeper, increasing resolution, and integrating diverse measurements and observations. Support for science projects is primarily awarded via a rigorous process of peer review of proposals submitted to the National Science Foundation.
Freely available, high precision data can be viewed as the most important legacy of the National Science Foundation's largest investment in solid-Earth Science.
The USArray component of EarthScope is a continental-scale seismic and magnetotelluric observatory designed to provide a foundation for integrated studies of continental lithosphere and deep Earth structure over a wide range of scales. USArray is providing a 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).
The USArray component of EarthScope is a continental-scale seismic observatory designed to provide a foundation for integrated studies of continental lithosphere and deep Earth structure. Over the wide frequency range of seismic waves transmitted through the Earth (hundreds of seconds to ten cycles per second), the sensors of the permanent and transportable seismic and magnetotelluric arrays will resolve the smallest background motions at the quietest of sites, while remaining “on scale” for all but the largest ground motions from regional earthquakes. USArray consists of of a portable array (the Transportable Array) of 400 seismometers that have been deployed across the United States over a 10-year period. In addition a "flexible component" array will be available to be deployed in areas where a denser network of seismometers is required. The Magnetotelluric Transportable (MT) Array comprises shorter-period investigations at hundreds of sites in the continental USA. Data from these sites are collected on a regular schedule through recovery of data storage modules. The USArray project is guided by the USArray Advisory Committee. For more information about the USArray observatory, visit the USArray website.
Seismic data holdings pertaining to all components of USArray, SAFOD, and PBO can be found at the IRIS Data Management Center (DMC). IRIS maintains data from regional networks, USArray network, and the EarthScope Magnetotelluric Array. In addition, the NCEDC maintains a separate multi-terabyte online copy of these seismic data.
All USArray data receive quality control at the IRIS Data Management Center (DMC), the Array Network Facility (ANF), the Array Operations Facility (AOF), or a Data Collection Center of the USGS in Albuquerque or Golden. Additionally, the IRIS DMC runs a suite of algorithms against all data arriving at the DMC in real time. In some cases, these algorithms are good indicators of data quality.
A primary objective of the PBO is to quantify three-dimensional deformation and its temporal variability across the active boundary zone between the Pacific and North American plates. Centimeter to millimeter-level measurements of surface and near surface motion through Global Positioning System (GPS) stations, borehole geophysics, laser strainmeters, accelerometers, and geodetic imaging has far reaching implications regarding earthquakes, volcanic unrest, subsidence, landslides, extraction or injection of fluids, loading or unloading of water, ice or snow, and other Earth processes.
Sounding of the atmosphere through GPS (i.e., satellite to receiver pathways) to measure total electron content in the ionosphere and precipitable water vapor in the troposphere impacts research regarding space weather, severe weather, and atmospheric dynamics. Probing of surface conditions through GPS reflectrometry (i.e., satellite to surface to receiver pathways) to measure soil moisture, snow depth, vegetation moisture index, and other features, provides crucial information regarding the water cycle and water resources. Advances in satellite systems through the Global Navigation Satellite System (GNSS) and innovations in GPS and GNSS receivers, other instrumentation, data processing, computing power, and cyberinfrastructure have allowed the scientific community to better address an array of critical scientific and societal problems using space and terrestrial geodetic techniques—in geographically distributed areas.
Complete information is available on the UNAVCO/PBO website.
The Plate Boundary Observatory collects, archives and distributes data from a broad networks of over 1100 GPS and seismic sites located across the continental United States and Alaska. These data are freely and openly available to the public, with equal access provided for all users. PBO data includes the raw data collected from each instrument; quality-checked data in formats commonly used by PBO's various user communities, and processed data such as calibrated time series, velocity fields, and error estimates.
One data access method for PBO GPS data is using the UNAVCO Data Archive Interface:
- Normal-rate (15-second sampled) data: PBO GPS Core Network
- High-rate (1-second and 0.2-second sampled) data: PBO High Rate
Requests for real-time GPS/GNSS data from the PBO network needs to be made by requesting an account by emailing email@example.com.
The PBO web page provides access to geodetic data from multiple instrument networks. The 1100-station GPS network is the largest component, and raw and processed data are available from PBO/GPS data product page and the UNAVCO Data Archive Interface. A subset of the GPS stations are streamed in realtime. Subnetworks of borehole strainmeters, borehole seismometers, tiltmeters, pore pressure sensors, and laser strainmeters are distributed in tectonic and volcanic regions of interest. Borehole data are accessible from PBO, Northern Califiornia Earthquake Data Center, and IRIS. PBO has collections of remote sensing data acquired as part of the GeoEarthScope project. Airborne LiDAR data can be obtained from the Open Topography Portal, and InSAR data can be obtained from the UNAVCO SAR Archive.
The San Andreas Fault Observatory at Depth (SAFOD) was a 3-kilometer deep hole drilled directly into the San Andreas Fault midway between San Francisco and Los Angeles, near Parkfield, CA. Located in an area that has ruptured six times since 1857, the hole provided the first opportunity to observe directly the conditions under which earthquakes occur, to collect rocks and fluids from the fault zone for laboratory study, and to continuously monitor the physical condition within an active earthquake nucleation zone.
The cores were collected from 3 different regions. First, two successful coring runs were conducted within sidetrack 'Hole E' starting around 10306 feet or 3.14126 km in measured depth. Then within sidetrack 'Hole_G', 3 coring runs were made across each of two actively creeping faults at 10,480 ft M.D. and 10,830 ft MD. Each core was cut into approximately 3 foot sections. For sections that the core could easily be removed from the aluminum core barrel, the scanned images include both front and back views. Images of the core are available here.
Data holdings from the SAFOD Project can be accessed on the International Continental Scientific Drilling Program (ICDP) and the Northern California Earthquake Data Center (NCEDC) website. The data consist mainly of cutting and mud sample reports, seismic data from borehole seismometers, core boxes, core logging, and lithological reports updated daily. The cores can be interactively viewed in EarthScope SAFOD Core Viewer. Images of the core are available here.
SAFOD physical samples are curated at the Gulf Coast Repository (GCR) at Texas A&M University, under the supervision of John Firth.
If you have core sampling questions or requests, please contact:
Judit Chester (firstname.lastname@example.org)
John Firth (email@example.com)
Links to some models and higher order data products developed by EarthScope researchers. This page complements the databases provided by the EarthScope facilities. We urge the research community to submit additional links to the EarthScope National Office.