U.S. Geological Survey       National Strong-Motion Program

Event Name: Big Bear City, California Earthquake
Event Date: 12/02/2000, 08:28 UTC, (00:28 AM PST)
Event Identification: 20001202_1
Recorder Type: K-2, Etna


Data Organization and Format ||  Downloads (updated 01/19/2001) ||  Tables (updated 01/19/2001)


Data Organization and Format

The December 02, 2000, 08:28 UTC ML 4.1 Big Bear City, California Earthquake data recorded by the USGS National Strong-Motion Network (NSMN) are available via the NSMP ftp server in the folder (directory) "20001202_1" (https://ca.water.usgs.gov/nsmp/20001202_1).    The time series provided are available in uncorrected acceleration, corrected acceleration, corrected velocity, corrected displacement, response spectra (relative displacement, relative velocity, pseudo-velocity, and absolute acceleration), and Fourier amplitude spectra of corrected acceleration.  All of the data are in SMC format.

In a departure from previous file-naming conventions (where for a particular channel the different the time series data all had the same filename, and thus required separate directories for each data type), the file names for the data have the following form:

uncorrected acceleration: RRRRc_u.smc
corrected acceleration: RRRRc_a.smc
corrected velocity: RRRRc_v.smc
corrected displacement RRRRc_d.smc
response spectra: RRRRc_r.rs2
Fourier amplitude spectra (f): RRRRc_f.fs1

where 'RRRR' is the four-digit recorder serial number (including leading 0's), 'c' is the channel number of the recorder ('a' corresponds to channel 1, 'b' to channel 2 , etc), the '_x' is used to identify the data type, and the suffix refers to the data format (rs2 and fs1 are valid SMC format types recognized by the BAP processing program.

The data are stored in two directories: uncorrected (only uncorrected acceleration) and corrected (all of the corrected and processed data, including acceleration, velocity, displacement, response spectra and Fourier amplitude spectra. This convention for organizing the data was implemented to avoid confusion between the directory names (Vol1, Vol2, … Vol6) previously used for some earlier events and the standard conventions for Volume1, Volume2 and Volume 3 processing.

Information on how the data are processed can be found in the section on DATA PROCESSING.


Downloads

To facilitate downloading the data, several subsets of the data have been compressed into PC compatible ".zip" format.  These same zip files are located in the "zips" folder in "20001202_1/" on the NSMP ftp server, "https://ca.water.usgs.gov/nsmp/20001202_1".

Files of uncorrected acceleration and corrected acceleration, velocity, and displacement for Episensors sensors were corrected for a polarity reversal error discovered in the original data (List of corrected files). The Fourier amplitude and response spectral data are unaffected by this correction." .  Users who downloaded data before 01/19/2001 should download the zip file 20001202_1_polarity.

20001202 BIG BEAR CITY EARTHQUAKE DOWNLOADS in ".zip" format

20001202_1_all.zip     uncorrected and corrected (3.7 Mb; uncompresses to 8.5 Mb; updated 01/19/2001)
20001202_1_uncorr.zip uncorrected (0.6 Mb; uncompresses to 1.5 Mb; updated 01/19/2001)
20001202_1_corr.zip corrected (3.2 Mb; uncompresses to 7.0 Mb; updated 01/19/2001)
20001202_1_polarity.zip polarity corrected data for sta 5300, S/N 1421 (0.7 Mb; uncompresses to 2.0 MB; posted 01/19/2001)

Tables

List of corrected peak ground accelerations and velocities for available time-series data; updated 01/19/2001 (to obtain list as Excel spreadsheet click here )


Return to top of page.
Return to Data Sets page
Return to NSMP Homepage

This page was posted on January 19, 2001.