Map
of California & Nevada earthquakes
BRIB - Briones Reserve, Orinda, CA, USA
Installation of BRIB borehole package |
1995/06/23 16:00:00 - Present
Latitude: 37.9189
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Work on the borehole |
Location |
Geology |
Vault Conditions
Instrumentation |
Network |
Operation Notes
Noise Characteristics |
Data Availability
- Location:
-
Site is located at the
Russell Reservation Field Station
of UC Berkeley's College of Natural Resources,
adjacent to
Briones Regional Park in Orinda, California.
This is a collaborative site with instrumentation for the
BDSN,
HFN,
BARD,
and the
USGS
strainmeter networks.
This site is known as SFRRL in the USGS network.
- Geology:
-
Sandstone
- Vault/Borehole conditions:
-
The instruments are sited in a borehole located on the Russell Reservation.
Geophysical instruments are installed at three levels in the 108-meter deep
hole. A dilatometer strainmeter, part of the
USGS
strainmeter network, is installed at the depth of
162 meters. Above the strainmeters, the 6-component
HFN
package is installed at a depth of 119 meters.
The Guralp CMG-3T seismometer of the
BDSN
is installed at a depth of 35 meters. The FBA-23 is
installed at the surface of the borehole. The
BARD GPS receiver
is located up the hill.
On 11/19/1996, the Seismological Laboratory installed a second CMG-3T in a small tank at the surface. Data recording of this sensor replaced the borehole instrument. This site experienced frequent tilts, primarily due to changes in ground water content. In the fall of 2000, BSL engineers installed a post-hole and relocated the Guralp CMG-3T from the borehole to this site. Recording of the post-hole installation began on 12/20/2000. The Guralp in the surface tank has been removed.
- Instrumentation:
-
Sensor Datalogger Start Date End Date SEED Channels Location AntennaCurrent Q330 2007/07/25 Present VE?,VE? 20 BF7 Q330 2007/07/25 Present BT?,LT?,VT? 20 Battery Voltage Q4120 2004/06/15 2007/07/25 AE? Battery Voltage Q935 2001/06/01 Present LE?,UE? ClockPhase Q330 2007/07/25 Present LC?,LC? 20 ClockQuality Q330 2007/07/25 Present LC?,LC? 10 Electric Field Dipole (Pb-PbCl or Cu-CuS Anodes) Q330 2007/07/25 Present VQ?,LQ?,BQ? 10 ElectroMagnetics Inc. BF4 Magnetometer Q330 2007/07/25 Present BT?,VT?,LT? 20 Guralp CMG-3 Broad Band Seismometer Q935 1995/07/07 2003/03/11 HH?,LH?,UH?,BH?,VH? Guralp CMG-3 Broad Band Seismometer Q935 2001/06/01 2003/03/11 UM? Guralp CMG-3T Broad Band Seismometer Q4120 2007/07/25 Present AE? Guralp CMG-3T Broad Band Seismometer Q935 2003/03/11 Present LH?,VH?,BH?,UM?,UH?,HH? InputVoltage Q330 2007/07/25 Present VE?,VE? 10 Internal Temperature Q935 2001/06/01 Present UK? Kinemetrics FBA ES-T Accel. (2 g max 10 v/g) Q935 2002/12/10 Present BL?,HL?,LL? Kinemetrics FBA-23 Accel. (2 g max 1.25 v/g) Q935 1995/07/07 2002/12/10 BL?,LL?,HL? Oyo GeoSpace GS-11 Horizontal Geophone Q4120 1995/06/23 Present DP?,LP?,BP?,EP? Oyo GeoSpace GS-11 Vertical Geophone Q4120 1995/06/23 Present BP?,LP?,EP?,DP? Sacks-Evertson Dilational Strainmeter Q935 1995/09/28 Present UV?,BV?,VV?,HV?,LV? Setra Systems Model 270 Barometer Q935 1996/04/09 Present LD? SystemCurrent Q330 2007/07/25 Present VE?,VE? 20 SystemTemperature Q330 2007/07/25 Present VK?,VK?,VP?,VP? 10 VCOValue Q330 2007/07/25 Present VC?,VC? 10 Wilcoxon 731A Accel. (0.5 g max 10 v/g) Q4120 1995/06/23 1995/07/24 HL?,LL?,CL?,BL? Wilcoxon 731A Accel. (0.5 g max 10 v/g) Q4120 1995/07/24 Present BL?,HL?,LL? The BRIB site also is home to a continuously operating GPS receiver as part of the BARD network.
- Network:
-
BK,UL (Berkeley Digital Seismic Network, Hayward Fault Network and USGS Low Frequency Network)
- Operation Notes: (may not be current)
- This section summarizes major changes in equipment or in instrumentation at BRIB.
- 06/15/2004: BH channels sampling rate changed from 20 Hz to 40 Hz.
- 12/20/2002: Vault flooded due to heavy rains.
- 12/20/2000: The downhole Guralp was removed and installed in a post-hole. Recording of this sensor replaces the tank Guralp.
- 03/23/2000: New BARD GPS monument installed, with Ashtech receiver.
- 03/06/2000: Newer version of MSHEAR loaded.
- 12/02/1999: Q4120 software upgraded to MSHEAR.
- 12/02/1997: Upgraded Q980 with 4 Gb disk and ethernet card.
- 04/04/1997: Replaced Q4120.
- 11/19/1996: A second Guralp seismometer installed on floor of surface tank. Recording of this sensor replaces the downhole Guralp.
- 04/02/1996: USGS barometer signal connected to Quanterra datalogger.
- 11/09/1995: Telemetry was switched from the ADN line to the frame relay connection.
- 09/28/1995: USGS dilatometer signal connected to Quanterra datalogger.
- 07/24/1995: Replaced Q4120.
- 07/07/1995: Installation of the BDSN package and recording system completed.
- 06/23/1995: Installation of the HFN package and recording system completed
- 08/06/1993: BARD GPS monument installed, with Ashtech receiver.
- 10/23/1992: Initial work on this site began.
- 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
- Instrument Response
- 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
- Requesting data
Help on using these tools is available.
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Berkeley Seismological Lab
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Copyright 1995-2005, The Regents of the University of California.
Last modified: Wed Jun 25 13:34:08 PDT 2008