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Event Name: Nenana Mountain, Alaska Earthquake
Event Date: 10/23/2002, 11:27 UTC (10/23/2002, 03:27 AM AKDT)
Event Identification: 20021023_1127
Recorder Type: custom
Data Organization and Format || Download (updated 02/13/2003)
The October 23, 2002 11:27 UTC Mw 6.7 Denali Fault, Alaska Earthquake data recorded by the Alyeska Pipeline Service Company ("Alyeska") are provided on a cooperative basis to the USGS The time series provided are available in original, raw acceleration. The raw data have had no processing done by the NSMP but have gone through onsite hardware filtering as described in the headers of the data files. The data were converted from g to cm/s/s using the constant 980.6650. All of the data are in SMC format:
| raw acceleration: | RRRRc.smc |
where 'RRRR' is the four-digit Alyeska station code, 'c' is the channel number of the recorder ('a' corresponds to channel 1, 'b' to channel 2 , etc). Standard USGS uncorrected data have the format RRRRc_u.smc.
Important
note to users of these data (posted 05/22/2003:
The
information in the headers of these files is revised from that in the headers of
the files originally served by the USGS. Changes
include:
1)
Revised information about the nominal filter characteristics, as
determined from an analysis of a circuit diagram for the filter.
Note
in particular that the highpass corner is at 0.1 Hz, not 0.01 Hz
as
was indicated in the files originally provided by Alyeska, and
that the highpass and lowpass filters each have 2 poles rather than 1.
Details of the nominal filter characteristics are provided in the
headers.
Due
to uncertainties in the instrument response, only
uncorrected acceleration time series data are currently being served.
Results from bench tests using components similar to those deployed in
the field show deviations from nominal characteristics that could produce
variations of up to 20% in displacements determined by double integration of the
acceleration time series. The USGS is working with Alyeska to determine more
accurate calibrations, and any new information will be released as soon as it is
available.
2)
The make and model of the digitizer, along with estimates of the
digitizing accuracy and precision are included.
3) Additional information about the baseline correction applied to the data.
The data are available as a zip file: raw (only original acceleration).
TAPS Borehole Logs available as individual PDF documents or zipped together into one file (added 02/13/2003).
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This page was posted on February 13, 2003; updated on May 22, 2003.