Station Information |
The Calpine Geysers seismic network, consisting of up to 49 different borehole
monitoring sites, was initially deployed and operated by the
Unocal Geothermal Division
on behalf of the geothermal energy producers in the California Geysers geothermal field.
In 1999, the Unocal geothermal fields at the Geysers were acquired by the
Calpine has continued Unocal's collaboration with the NCEDC and has made
data available for public distribution.
The Calpine/Unocal Geysers dataset is a collection of digial microearthquake
seismograms recorded by this network. Over 10 years of digital
microearthquake seismograms (1989 through 2000) have been released
for archiving and distribution through the NCEDC.
Calpine has also released an unedited earthquake catalog for events in
1995-1998 with approximate times and very rough hypocenters for some of the
event represented in the time series, primarily as an index aid for the
waveforms. Calpine makes no claims that this catalog is complete in any
manner, and assumes no responsibilty for the accuracy or usefulness of the
- Network Code
- Station information
The Geysers network has evolved over time, with different station
configurations and different recording systems. In 1989, the
w array covered the northeastern part of the field and was
operated for about a year, using a Sprengnether processer called
QLog. In late 1989, the station coverage was expanded
fieldwide and the QLog was replaced with an Owl processor
(g array), with some overlap between the two systems.
In 1992, the Owl processer was replaced with an IASPEI system
The Geysers sensors are deployed in a combination of surface
and borehole installations. The borehole stations are SB4B,
SQK, DXR, STY, FUM, FNF, TCH, and DVB. The sensors are HS-1,
with data digitized at 100 sps.
The orientation of the surface sensors is denoted by the channel
name - e.g. ***N and ***E. The borehole sensors are not oriented
and are typically named ***X and ***Y.
- Data Access
The 1989-2000 microearthquake waveform data are available in its native PCQL
research accounts at the
- w array - 1989.001 through 1989.365.
- g array - 1989.279 through 1992.218.
- f array - 1992.218 through 2000.366.
Several program exist to convert
the data to AH or MiniSEED format:
pcql2ah - convert PCQL data to Lamont AH xdr format.
pcql2ms - convert PCQL data to MiniSEED Steim1 format.
The unedited earthquake catalog for events is available: