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Help and Documentation

Acknowledge the NCEDC

Cite the NCEDC:

"NCEDC (2014), Northern California Earthquake Data Center. UC Berkeley Seismological Laboratory. Dataset. doi:10.7932/NCEDC."

Acknowledge the NCEDC:

"Waveform data, metadata, or data products for this study were accessed through the Northern California Earthquake Data Center (NCEDC), doi:10.7932/NCEDC."

Please use these statements in your publication acknowledgments.

Click on each topic below to expand to more information.

Catalog Searches

The NCEDC provides online search capabilities for the northern California earthquake catalogs of the USGS and BSL,

for the worldwide earthquake catalog of the ANSS,

and for the Enhanced Geothermal Systems (EGS) catalog.

Waveform Station and Channel Inventory Tools

Through SeismiQuery and NetDC, you may check the inventory of the NCEDC, seeing what stations or channels are available for different time periods.

SeismiQuery

SeismiQuery was developed by the IRIS Data Management Center to provide a simple interface for making information queries and reviewing data holdings. The NCEDC has implemented SeismiQuery as a tool for querying the waveform archives. However, this interface is NOT currently configured to retrieve waveform data.

Help using SeismiQuery is available here.

NetDC System

The NCEDC has collaborated with the IRIS Data Management Center on the development of tools to link seismological data centers. The Networked Data Centers (NetDC) system is one example. The NCEDC implemented NetDC and developed a simple form which allows users to make inquiries about the availablility/inventory of waveform data at the NCEDC.

Help using the NetDC request form is available here.
Examples of NetDC requests are here.
NetDC requests may also be submitted by email to netdc@ncedc.org.

Retrieving waveform data

Web Services

The NCEDC has created a new set of FDSN-compliant web services to access data at the NCEDC. Web services provide simple functions that can be used from a web browser, command-line programs such as curl and wget, dedicated clients, and through programming languages such as perl, python, shell scripts, or MATLAB.

The FDSN web services provide a common specificiation to access common FDSN data types such as event information, station and information, and waveform data. The FDSN web services specification serves as a baseline level of compatibility, allowing data request tools to work with any FDSN data center that implementing these services.

Why web services? Web services at the NCEDC use a RESTful (Representational State Transfer) design to provide a simple stateless query and data retrieval system. RESTful Web services use the HTTP protocol and normally communicate with clients using TCP port 80, which is the default port used by web servers. Using HTTP and standard web server ports minimizes interference from firewalls, and allows you to use web services anywhere you can use a web browser -- from behind most firewalls, and through web proxies.

The NCEDC FDSN web services are designed to be compatible with the FDSN web services implemented at other FDSN data centers such as the IRIS DMC Web Services. Please visit the NCEDC Web Services Web Page for a complete list of NCEDC Web services and descriptions.

Web Services retrieve data in miniSEED format (no instrument response metadata). Instrument response metadata can be retrieved through web services as dataless seed (readable with rdseed), resp file format, or station XML. Full network IR metadata is available in our network directories

SWC

The Simple Waveform Client (SWC) is a command-line program for easily dowloading waveform retrieval from the NCEDC Archive and NCEDC DART (Data Available in Real Time). Download SWC

SWC retrieves data in miniSEED format (no instrument response metadata). Instrument response metadata can be retrieved through web services as dataless seed (readable with rdseed), resp file format, or station XML. Full network IR metadata is available in our network directories

DART (Real-Time Data)

DART (Data Available in Real Time) is a buffer of real-time telemetry MiniSEED data that is accessible through SWC or Web Services, or through a filesystem accessible through the web. miniSEED format has no instrument response metadata. Instrument response metadata can be retrieved through web services as dataless seed (readable with rdseed), resp file format, or station XML. Full network IR metadata is available in our network directories

STP

The Seismogram Transfer Program or STP is a simple client-server program, developed at the SCEDC. Access to STP is either through a simple direct interface that is available for Sun or Linux platforms, or through a GUI Web interface. With the direct interface, the data are placed directly on a user's computer in several possible formats, with the byte-swap conversion performed automatically. With the Web interface, the selected and converted data are retrieved with a single FTP command. The STP interface also allows rapid access to parametric data such as hypocenters and phases.

A command-line STP client program, tested under Solaris (Unix) and Linux, can be downloaded from the directory

http://www.ncedc.org/ftp/pub/programs/stp/

STP retrieves data in full SEED format (data and instrument response metadata). The program rdseed will extract station/channel instrument responses, and convert the waveforms into other user formats such as miniSEED.

Email-based tools: NetDC System, EVT_FAST, and BREQ_FAST

The NCEDC's older NetDC system provides a simple tool for requesting waveform data.

Help using the NetDC request form is available here.
Examples of NetDC requests are here.
NetDC requests may also be submitted by email to netdc@ncedc.org.

Data from the NC network is available over the Web using a request form:

The Seismogram Transfer Program or STP is a simple client-server program, developed at the SCEDC. Access to STP is either through a simple direct interface that is available for Sun or Linux platforms, or through a GUI Web interface. With the direct interface, the data are placed directly on a user's computer in several possible formats, with the byte-swap conversion performed automatically. With the Web interface, the selected and converted data are retrieved with a single FTP command. The STP interface also allows rapid access to parametric data such as hypocenters and phases.

A command-line STP client program, tested under Solaris (Unix) and Linux, can be downloaded from the directory

http://www.ncedc.org/ftp/pub/programs/stp/

NetDC System, EVT_FAST, and STP retrieve data in full SEED format (data and instrument response metadata). The program rdseed will extract station/channel instrument responses, and convert the waveforms into other user formats such as miniSEED.

Data Formats

Earthquake Catalogs

Catalog and phase files at NCEDC are stored and retrieved in different formats for each data set. Overviews are available for the following catalogs:

These are the current formats supported by the NCEDC:

Waveform data

There are two commonly used time series file formats used by the the seismological community: SEED/miniSEED and SAC.

SEED format and the rdseed program:

As much as possible, waveform data archived at the NCEDC are made available in SEED (Standard for the Exchange of Earthquake Data) format.

The Standard for the Exchange of Earthquake Data (SEED) is an international standard format for the exchange of digital seismological data. SEED was designed for use by the earthquake research community, primarily for the exchange between institutions of unprocessed Earth motion data.

SEED files normally contain the digital timeseries as well as station and channel information describing the complete instrument response for each time series.

SEED is defined and developed by the FDSN Working Group on data exchange.

An Introduction to SEED provides an overview of the SEED format. The SEED Manual (PDF) describes the complete SEED format.

IRIS has developed and freely distributes the program rdseed which will read SEED files, extract station/channel instrument responses, and convert the seismograms to other standard user format such as AH, SAC, CSS, and miniSEED formats. The rdseed program is available from the IRIS DMC

miniSEED

Our newer services retrieve data in miniSEED format. miniSEED does not include instrument response metadata. Instrument response information can be retrieved as dataless seed (readable with rdseed), resp file format, or station XML.

  • Station XML format response metadata can be retrieved through web services' fdsnws-station via a targeted query.
  • Dataless seed format response information (readable with rdseed) can be retrieved through web services' ws-dataless via a targeted query.
  • Resp file format response information (rdseed not needed) is available in our network directories by network (larger file with response information for all stations, all channels, for all time). A targeted query through web services' ws-resp is also available.

SAC format description (IRIS website)

Acknowledging/Citing the NCEDC

When you use data from this data center, please acknowledge both the Northern California Earthquake Data Center (NCEDC) and the organization(s) that contributed the data to the NCEDC.
Table of contributing organizations

Database Project

The NCEDC has a developed a schema for earthquake data in collaboration with partners in southern California.

NCEDC Background and Reports

Information about the operation of the NCEDC is available from the Annual Reports of the Berkeley Seismological Lab.

Catalog Format Descriptions

Catalogs
Agency/Network Catalog File Formats
BSL Northern California and surrounding areas: hypocenters, magnitudes, phase and amplitude readings, 1910-present (hypo and mag), 1984-present (phase and amp)[Now merged with USGS catalog)
USGS Northern California hypocenters and magnitudes, phase and amplitude readings, first-motion mechanisms, 1967-present (now merged with BSL catalog)
Townley-Allen Catalog
ANSS