MHDL - Marin Headlands, GG Nat'l Rec. Area, 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 MHDL (MHDL)
In Operation 2006/05/17 23:00:00 - Present
Latitude
Longitude:
Elevation: 94.5 meters
Instrumentation Borehole
GPS
Other

Location

MHDL is located in the Marin Headlands of the Golden Gate National Recreation Area and was installed under the auspices of the National Park Service. This site is known as SFMAR in the USGS Low Frequency Network.

Although the installation is not complete as far as the data acquisition using the Quanterra datalogger, the USGS satellite system is installed and operational.

Network

Mini Plate Boundary Observatory Network (BK)
Bay Area Regional Deformation Network Network (BARD)

Geology

TBD

Borehole Conditions

The MiniPBO borehole was installed on 08/06/2002. The strainmeter was installed at 520.6 ft and the seismometer package at 489.2 ft depth. This figure shows the location of equipment in the borehole.

GPS Monument Description

Threaded 5/8" rod cemented into concrete vault, in turn cemented onto bedrock

Seismic Station Pictures

View from the Marin Headlands

View from the Marin Headlands

Installation of strainmeter at MHDL<br>Courtesy of the USGS

Installation of strainmeter at MHDL
Courtesy of the USGS

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

MHDL

MHDL

MHDL

MHDL

Table of Seismic Instrumentation

SensorDataloggerSEED ChannelsLocation
GeophoneMark Products L-22 Horizontal GeophoneQ330-GFEEP?,LP?,SP?40
Mark Products L-22 Vertical GeophoneQ330-GFEEP?,LP?,SP?40
ReceiverAntennaRadome-
GPSTopcon Net-G3AAshtech Choke-RingSCIGN Short-
SensorDataloggerSEED ChannelsLocation
OthersBF7Q330BT?,LT?,VT?20
ElectroMagnetics Inc. BF4 MagnetometerQ330BT?,LT?,VT?20
Paroscientific 8WD Digital Pressure MeterQ330-GFELD?40
Sacks 3-component Tensor StrainmeterQ330-GFEBS?,HS?,LS?40
Pinnacle5000QEPBA?,LA?EP
AuxiliaryVCOValueQ330-GFE
AntennaCurrentQ330-GFEVK?40
ClockPhaseQ330-GFEVE?40
ClockQualityQ330-GFEVE?40
SystemCurrentQ330-GFEVC?40
InputVoltageQEPLK?EP
InternalHumidityQEPLI?EP
InternalPressureQEPLD?EP
InternalTemperatureQEPLK?EP
PLLOffsetQEPLC?EP
Setra Systems Model 270 BarometerQEPLD?EP
SystemTemperatureQEPLK?EP

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

Waveform Data



GPS Data

Noise Analysis

View more noise plots

GPS Data Quality


Completeness

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
MHDL completeness last year
Lifetime
MHDL completeness lifetime

Multipath

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
MHDL multipath last year
Lifetime
MHDL multipath lifetime