Description
Data products derived from raw data are produced both by the scientific community and by
EarthScope Data
Services (DS). These products complement the basic raw-data products, such as
event-segmented waveforms,
which remain available through EarthScope’s traditional data access mechanisms. This
repository hosts the
artifacts generated by these derived products. For more information on the NSF NGF data
products, please visit
the NSF NGF Seismology Data Products
page.
Table of Contents
EARS Data Product
The EarthScope Automated Receiver Survey (EARS)
was a fully automated data product designed to query EarthScope Web Services
and calculate bulk crustal properties of seismic stations as new data arrived.
Before August 5, 2013, EARS monitored the
USGS/NEIC Weekly PDE (WHDF) catalog for new seismic events.
After this date, it transitioned to querying EarthScope Web Services.
Processing Overview
EARS followed a sequence that:
Calculated receiver functions from seismic waveforms.
Transformed receiver functions from the amplitude-time domain to
amplitude as a function of crustal thickness (H) and the Vp/Vs ratio
(K).
Utilized predicted travel times of Ps, PpPs, and PsPs/PpPs phases
over a suite of single-layer models.
Weighted H and K values based on the instantaneous phase of the receiver
functions.
Formed an HK stack for each station to estimate its
crustal thickness and Vp/Vs ratio.
Coverage and Expansion
EARS dynamically extended its coverage as new seismic stations became available.
With the Transportable Array (TA) component of the USArray
rolling
eastward,
EARS coverage of the continental United States expanded over time.
EARS Retirement and Data Archive
As part of the transition of NSF NGF Data Products to the cloud, the EARS data product was retired
at the
end
of June 2024. The archived data has been preserved and is now accessible at the EARS
Data
Archive
Repository
Archived Data Structure
EARS Data Directory
The EARS archive consists of the following directories:
EARS/
├── events/
└── summary/
events Directory Structure
The events directory contains earthquake event data from 1990 through June 2024. The data are
organized by
year,
event, network, and station:
Each station directory contains the following files:
Analytic_PpPs.xy, Analytic_Ps.xy, Analytic_PsPs.xy - Receiver function
amplitude
data for
different seismic phases, used in crustal thickness estimation.
HKStack.xy - Results of the H-K stacking method, estimating crustal
thickness and
Vp/Vs
ratio.
BHE.sac, BHN.sac - Seismic waveform data recorded on East-West (BHE) and
North-South (BHN)
components.
BHZ.sac - Seismic waveform data recorded on the vertical component (BHZ),
providing
essential depth information.
ITR.sac, ITT.sac - Intermediate and transverse component waveform files
used in
seismic
data processing.
Event Data by Year
The table below contains links to each year’s folder under the events folder.
The summary directory stores processed results from EARS, including crustal thickness and seismic
velocity
ratios, organized by network and station:
summary/
├── 1A/
│ └── UO1A/
Each station summary folder contains the following files:
SumHKStack.xy - Summary results of the H-K stacking for the station.
SumHKStackImage.png - Image representation of SumHKStack.
SumHKStackTxt.xyz - Contains text-based summary results of the H-K stacking
analysis.
eventAzPlot.png - Azimuthal distribution plot of recorded events for the
station.
station_local.html and downloaded_content - An HTML summary page for the
station,
containing a structured overview of the station data.
Summary Data Map (Stations Summary/Recap)
Below is an interactive map containing all stations processed by ears with a summary of
the results for each station.
Click on a station marker to view the summary results for that station.
Summary Data by Network (Stations Summary/Recap)
The table below contains links to each station folder under the summary/network folder.