Parkfield High-Resolution Seismic Network Overview

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).

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

Network Code

BP

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

All 13 stations are up and running.  Current projects include noise reduction at all sites.

Station Information

• Map of the HRSN stations
• BP Information Directory, including
  • List of station locations
  • List of available channels
    • Year/month/day format
    • Year,doy format
  • Instrument Response
    • SEED format
    • Simplified Responses
• History and Background of the HRSN
• Table of HRSN stations
• Reports on the HRSN from the Annual Report of the BSL:
  • 2001-2002
  • 2000-2001
  • 1999-2000
  • 1998-1999
  • Related research
• Karageorgi et al., BSSA, 82, 1388-1415, 1992.

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.

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

Help on using these tools is available.

Older waveform data are available through research accounts. Please see the information on HRSN access for complete information on HRSN data.

Collaborations

The High-Resolution Seismic Network was deployed in colloboration 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.