BRIB - Briones Reserve, Orinda, CA, USA
We operate broadband and borehole stations under the network code BK. The Berkeley Digital Seismic Network (BDSN) is a regional network of very broadband and strong motion seismic stations designed to monitor regional seismic activity as well as provide high quality data. The Berkeley borehole stations have borehole geophones or other seismic sensors and may have other geophysical instrumentation.
BARD is our GPS network for monitoring crustal deformation across the Pacific-North America plate boundary and in the San Francisco Bay Area for earthquake hazard reduction studies and rapid earthquake emergency response assessment
|Station Name||BRIB (BRIB)|
|In Operation||1995/06/23 16:00:00 - Present|
LocationSite 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.
NetworkBerkeley Digital Seismic Network (BK)
Northern Hayward Fault Network (BK)
Mini Plate Boundary Observatory Network (BK)
Bay Area Regional Deformation Network Network (BARD)
USGS Low Frequency Network (UL)
Borehole ConditionsThe 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.
GPS Monument DescriptionPoured concrete cylinder with steel reinforcement
Seismic Station Pictures
Installation of BRIB borehole package
Work on the borehole
- Time series processing at the BSL
Last year Clean Clean & detrended Raw Raw & detrended Lifetime Clean Clean & detrended Raw Raw & detrended Text file (final results only) Clean Raw
GPS Station Pictures
Table of Seismic Instrumentation
|Broadband||Guralp CMG-3T Broad Band Seismometer||Q330HR-GFE||BH?,HH?,LH?,VH?||00|
|Accelerometer||Kinemetrics FBA ES-T Accel. GFE (4 g max 5 v/g)||Q330HR-GFE||HN?||00|
|Wilcoxon 731A Accel. (0.5 g max 10 v/g)||BASALT8X||BN?,CN?,LN?||40|
|Geophone||Oyo GeoSpace GS-11 Horizontal Geophone||BASALT8X||DP?,LP?,SP?||40|
|Oyo GeoSpace GS-11 Vertical Geophone||BASALT8X||DP?,LP?,SP?||40|
|GPS||Septentrio PolaRx5||Ashtech Choke-Ring||SCIGN Tall||-|
|Electric Field Dipole (Pb-PbCl or Cu-CuS Anodes)||Q330||BQ?,LQ?,VQ?||10|
|ElectroMagnetics Inc. BF4 Magnetometer||Q330||BT?,LT?,VT?||20|
|Sacks-Evertson Dilational Strainmeter||BASALT8X||BV?,HV?,LV?||40|
Waveforms and associated metadata, and GPS data, are available at the Northern California Earthquake Data Center (NCEDC).
- BK Information Directory, including
Data completeness is defined both as "Completeness of observations" and "Cycle slips per observation". "Completeness of Obs." is the number of epochs in the final RINEX file normalized to the expected number. This percentage will go down if time is missing from the RINEX file. "Cycle slips per Obs." is the total number of detected cycle slip normalized to the total number of observations in the RINEX file. This number will increase as the receiver loses lock on satellites more frequently.
The effects of multipath on the data are estimated by parameters for L1 and L2 (MP1 and MP2 respectively); see Estey and Meertens (GPS Solutions, 1999) for derivation. The daily value is the RMS of MP1 and MP2 throughout the day and for all satellites. Higher values indicate a greater prevalence and/or strength of multipathing, i.e. objects on the ground are providing multiple reflection pathways from the satellite to antenna.