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Entrance to YBH adit

1993/07/24 01:03:00 - Present Latitude: 41.7320 Longitude: -122.7104 Elevation: 1059.70 meters

Typical STS-1 installation

Location | Geology | Vault Conditions
Instrumentation | Network | Operation Notes
Noise Characteristics | Data Availability

Location:

Site is located in the Klamath National Forest.

YBH is an auxillary station used by the Prepatory Commission for the Comprehensive Test Ban Treaty Organization. The STS-2 installed in 2002 supports CTBTO activities.

Geology:

Metavolcanics

Vault/Borehole conditions:

The sensors are located in an abandoned mining adit, approximately 115' from the entrance, on a poured concrete pier. Approximately 75 meters of overburden cover the adit. The seismometers are thermally insulated with 2" of polyurethane foam. The datalogger and supporting equipment are located approximately 50' from the entrance to the adit.

Instrumentation:

Sensor	Datalogger	Start Date	End Date	SEED Channels	Location
Battery Voltage	Q935	2001/06/01	Present	LE?,UE?
Druck PTX-1240 Barometric Sensor	Q935	2002/11/01	Present	LD?
Internal Temperature	Q935	2001/06/01	Present	UK?
Kinemetrics FBA ES-T Accel. (2 g max 10 v/g)	Q935	2004/11/18	Present	BL?,HL?,LL?
Kinemetrics FBA-23 Accel. (2 g max 1.25 v/g)	Q935	1993/07/24	2004/11/18	LL?,HL?,BL?
Motorola MPX201 Pressure	Q935	1996/05/17	Present	LD?
Streckeisen STS-1 VBB Feedback Seismometer	Q935	1993/07/24	1996/05/17	LH?,BH?,VH?,UH?,HH?
Streckeisen STS-1 VBB Feedback Seismometer	Q935	1996/10/22	2004/06/15	BH?,HH?,LH?,UH?,VH?
Streckeisen STS-1 VBB Feedback Seismometer	Q935	2001/06/01	2004/06/15	UM?
Streckeisen STS-1 VBB Feedback Seismometer	Q935	2004/06/15	Present	LH?,HH?,UH?,VH?,UM?,BH?
Streckeisen STS-2 VBB Tri-Axial Seismometer	Q935	1996/05/17	1996/10/21	BH?,HH?,VH?,UH?,LH?
Streckeisen STS-2 VBB Tri-Axial Seismometer	Q935	2002/11/01	2004/06/15	UH?,LH?,HH?,BH?,UM?,VH?
Streckeisen STS-2 VBB Tri-Axial Seismometer	Q935	2004/06/15	Present	HH?,LH?,UH?,BH?,VH?
YSI 44031 Thermistor	Q935	1996/05/17	Present	LK?

The YBH site also is home to a continuously operating GPS receiver (YHBB) as part of the BARD network.

Network:

BK (Berkeley Digital Seismic Network)

Operation Notes: (may not be current)

This section summarizes major changes in equipment or in instrumentation at YBH.

• 06/15/2004: Changed BH channels sampling rate to 40 Hz.
• 10/31/2002: Install CNTBTO STS-2.
• 05/28/2002: Installed Druck barometer system.
• 12/1999: MSHEAR installed to replace USHEAR software.
• 10/21/1996: The STS-1 instrument was re-installed.
• 05/17/1996: The STS-1 instrument was replaced with an STS-2 temporarily, in order to fix a problem in the vertical component of the STS-1.
• 05/13/1996: Frame-relay circuit installed. Termperature/pressure package installed.
• 07/24/1993: A Streckeisen STS-1 and a Kinemetrics FBA-23 were installed with a Quanterra Q980 digitizer.

Noise Characteristics:

The figures below are cumulative plots of power spectral density (psd) determined from the broadband channels. In each figure, the vertical component psd is plotted with blue diamonds, the north component psd with red squares, and the east component psd with green circles. The results are presented in the 5 different frequency bands, and the USGS/Albuquerque low noise model is plotted as a dashed line in each. The PSD units are in dB (decibel) relative to 1 (m/s**2)**2/Hz. The current annual plot is updated weekly.

Cumulative PSD results
1999	2000	2001	2002	2003	2004	2005

Data Availability:

BDSN waveforms and associated metadata are available at the Northern California Earthquake Data Center (NCEDC).

• Map of BDSN stations
• Table of BDSN stations
• BK Information Directory, including
  • List of station locations
  • List of available channels
    • Year/month/day format
    • Year,doy format
  • Instrument Response
    • SEED format
    • Simplified Responses
• Information on Quanterra Timing Errors
• Information on Quanterra 4120 FIR Filter changes - 6/30/2003
• Information on BH sampling rate change - 06/15/2004
• View digital seismograms

Several tools provide access to SEED format data at the NCEDC, both in terms of querying the archives and allowing data requests.

• Querying the archives
  • SeismiQuery at the NCEDC
  • NetDC Request Form
• Requesting data
  • NetDC Request Form

Help on using these tools is available.