Parkfield High-Resolution Seismic Network Overview

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The High-Resolution Seismic Network (HRSN) is one of several networks of seismic instrumentation in northern and central California operated by the Berkeley Seismological Laboratory. The HRSN is an array of borehole instrumentation deployed in the Parkfield area, with the goal of monitoring microseismicity on the San Andreas fault.

The HRSN was initially deployed with 10 borehole stations in 1986 as part of a Vibroseis project during the Parkfield Prediction Experiment. It was quickly discovered that the earthquake data were well-recorded, so the system was upgraded in 1987 with accurate timing and triggering capabilities to capture the approximately daily local microearthquakes.

The HRSN background describes the goals and design of the network and outlines the characteristics of the earthquake data set for the 1987-1998 time period. We strongly suggest that you read this document before using any of the HRSN earthquake data (particularly the older data).

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Gastro Peak Repeater Station

Over the years, the network has evolved and the operation of the HRSN can be divided into three stages:

  • 1987-1998: Original HRSN data acquisition
  • 1998-2000: PASSCAL RefTek recorders
  • 2001-present: Q730 dataloggers and expansion to 13 stations
The latest stage was initiated in the fall of 2000 with the installation of Quanterra dataloggers and the addition of 3 new borehole stations.

Network Code

Current Station Equipment
3-component Mark Products L22 or Geospace HS1 or Litton 1023 sensor
Two Electrodes for EM studies on CCRB, LCCB, and SCYB
24-bit Quanterra digital data logger
80x preamplifier
GPS clock
Continuous telemetry to a central site; triggered events shipped to UC Berkeley
Backup power supply

Typical Recorded Channels
Sensor SEED Channels Rate (samples/sec) Sampling Mode FIR Filter
Geophone DP1, DP2, DP3 250.0 Continuous (for centralized triggering) Casual
Geophone BP1, BP2, BP3 20.0 Continuous (for centralized triggering) Acasual
Vertical Electric array (CCRB,LCCB,SCYB) Data are not being recorded at this time

Network State of Health
Current projects include noise reduction at all sites.

Station Information

Data access
The HRSN has evolved over time, with different recording systems and the addition of new stations in 2000-2001. Data since March 2001 are available in SEED format. Several tools provide access to SEED format data at the NCEDC, both in terms of querying the archives and allowing data requests.

Help on using these tools is available.

Please see the information on HRSN access for complete information on older HRSN data.

The High-Resolution Seismic Network was deployed in collaboration with LBNL. The recent network upgrade with the installation of Quanterra dataloggers and the addition of 3 new borehole stations is designed to provide coverage for the San Andreas Fault Observatory at Depth (SAFOD) drilling target with funding provided by the USGS and NSF.