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125 Years of Sound Science, serving society

MHC - Lick Observatory, Mt. Hamiliton, CA, USA

Station Name MHC (MHCB)
In Operation 1986/09/10 00:00:00 - Present
Elevation: 1250.40 meters
Instrumentation Broadband

  • Site


    Site is located at the Lick Observatory atop Mount Hamilton, and is under the auspices of UC Santa Cruz. The site was first established in 1887 with the installation of the first seismic sensors in North America, and has been occupied continuously since then. Wood-Anderson seismographs were deployed at this site in 1928 and operated until 1993. The first digital broadband instrumentation was deployed in 1987.


    BK, BARD (Berkeley Digital Seismic Network and Bay Area Regional Deformation Network)


    Jurassic-Cretaceous Franciscan greywacke and greenstone

    Vault/Borehole Conditions

    The vault is located in a room in the east wing of the Lick Observatory. The piers are reinforced concrete which are isolated from the building. The seismometer room is isolated from the hallway via two doors and the datalogger and supporting equipment are in an adjacent room. The seismometers are thermally insulated with 4" of polyurethane foam.

    GPS Monument Description

    Threaded 5/8" rod cemented into roof of concrete building.
  • Plots & Figures

    Seismic Station Pictures

    View of the dome at MHC

    View of the dome at MHC

    Typical STS-1 installation

    Typical STS-1 installation

    GPS Station Timeseries

    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





  • Instrumentation

    Table of Seismic Instrumentation

    SensorDataloggerSEED ChannelsLocation
    BroadbandStreckeisen STS-1 VBB Feedback SeismometerQ330HR-GFEBH?,HH?,LH?,VH?00
    AccelerometerKinemetrics FBA ES-T Accel. (2 g max 10 v/g)Q330HR-GFEHN?00
    GPSTrimble NetRSAshtech Choke-RingSCIGN Short-
    SensorDataloggerSEED ChannelsLocation
  • Data & Metadata

    Waveforms and associated metadata, and GPS data, are available at the Northern California Earthquake Data Center (NCEDC).

    Waveform Data

    GPS Data

  • Data Quality

    Noise Analysis

    View more noise plots

    GPS Data Quality


    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.

    Previous Year
    MHCB completeness last year
    MHCB completeness lifetime


    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.

    Previous Year
    MHCB multipath last year
    MHCB multipath lifetime