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What is recorded at a PBO BSM site? Strainmeter Seismometer Barometer Rainfall gauge Temperature sensor Strainmeter Seismometer Barometer Rainfall gauge Temperature sensor

What is recorded at a PBO BSM site? Strainmeter Seismometer Barometer Rainfall gauge Temperature sensor Strainmeter Seismometer Barometer Rainfall gauge Temperature sensor Tiltmeter GPS Accelerometer Pore pressure sensor

What is recorded at a PBO BSM site? TypeRate (sps)Archive FormatFrequency Strain20 1 1/600 Bottle, SEED Bottle, SEED, ASCII Hourly Daily Environmental1/300Bottle, SEED, ASCIIDaily Barometer1SEEDStreaming Seismic1, 100SEEDStreaming Pore pressure1/300ASCIIDaily Tiltmeter1ASCIIDaily

Strainmeter Dataflow SEED –The data are translated to miniSEED by PBO –Transferred to NCEDC and IRIS DMC via SEEDLink –Data downloaded from logger oh hourly basis ASCII –Low frequency bottle data also translated to ASCII and made available from PBO web site Updated every hour Updated every day Strainmeter Logger UNAVCO Convert to mSEED Collect bottle files UNAVCO - BSMAC Monitor dataflow, quality Track metadata, archiving Process data Updated every 2 weeks

The PBO Strainmeter Page A master list of all PBO strainmeter data sets is displayed on the PBO strainmeter products web page.

Raw Data: All sample rates Archived at the DMC and the NCEDC SEED format Bottle format: 24-hour long files

Raw Data: Low Frequency UNAVCO provides: Bottle format: Long-term merged data ASCII format: Long-term merged ASCII data

Processed Data Processed Strainmeter data Gauge, areal and shear strain Edits Tidal Correction Barometeric Pressure Correction Borehole Trend Correction

Processed Data Processing StepMethod 1. Decimate, linearizeMinimum phase, causal FIR filters 2. Edit & estimate offsetsTSVIEW, PIASD (CLEANSTRAIN) 3. Borehole TrendsLinear & exponential model 4. Tidal ModelBAYTAP-G, PIASD 5. Barometric ResponseBAYTAP-G, PIASD 6. Areal and shear strainGenerated with nominal scale factors

Processing Steps 1 sps data Decimate, linearize - Edit data edits record Remove predicted signals Remove borehole trend, tides, barometric pressure 300s data

Processing Steps 1 sps data Decimate, linearize - Edit data edits record Remove predicted signals Remove borehole trend, tides, barometric pressure 300s data Apply edits Generate borehole trend, tides, baro corrections Generate areal, shear strain Level 2 XML 300s data

Processing Steps 1 sps data Decimate, linearize - Edit data edits record Remove predicted signals Remove borehole trend, tides, barometric pressure 300s data Apply edits Generate borehole trend, tides, baro corrections Generate areal, shear strain Level 2 XML 300s data

Two categories of processed data: 2a:Rapidly processed data set Updated every 14 days 2b: Post-processed data set Trends and tides recalculated Models updated every 4 months Processed Strainmeter Data

Step 1. Decimate, Linearize SEED and bottle data are in digital counts. The linear gauge strain, u, at time t, is calculated with respect to a fixed raw data point (d o ). d t /(1e+8) 1-(d t /1e+8) d o /(1e+8) 1-(d o /1e+8) * RMRM u t = d t raw data value at time t Rinstrument reference gap (0.01 or 0.02 cm) Minstrument diameter (0.087 m)

Step 2. Edit Inspection of 100% 1-sps strain data Flag signals known to not be tectonic Use PIASD to estimate offset - moving to cleanstrain+ Edit low frequency barometric data

Step 2. Edit 2. Editing B007, Shores, WA Counts CH0 CH1 CH2 CH3

Step 3. Detrend 2. Editing Current Method Trends are modeled by fitting a linear term plus one to two exponentials to the data Goals Transparency Repeatability

Step 3. Detrend B087, Ford Ranch, Anza Installed June 2006

ch2= *exp( *t)-0.043*t Days since install microstrain April 4, 2007 Days since install microstrain Step 3. Detrend B087, Ford Ranch, Anza CH2 Model CH2

July 13, 2007 ch2= *exp( *t)-0.043*t microstrain CH2 Model Step 3. Detrend B087, Ford Ranch, Anza Days since install

ch2= *exp( *t)-0.043*t ch2= *exp( *t)-0.025*t Days since install microstrain CH2 Model Updated Model July 13, 2007 microstrain Step 3. Detrend B087, Ford Ranch, Anza Days since install

Step 4. Tides a. Input linearized edited data to BAYTAP-G - Estimate amplitude and phase of tides b. Compute time series correction using PIASD - Uses output from BAYTAP-G

Edited Gauge Data BAYTAP-G PIASD Correction Step 4. Tides B081 Keene Wilde Anza Tide removed microstrain B081 Keene Wilde Anza

Step 5. Barometric Correction Assume strain change linearly related to barometric pressure change Estimate simultaneously with tides using BAYTAP-G

Step 5. Barometric Correction B081 Keene Wilde Anza Pressure removed microstrain Edited Gauge Data BAYTAP-G Response Coefficient

Step 6. Areal and shear strain u i linearized gauge readings g i gauge weightings ( currently 1)   orientation of gauge counter-clockwise from east Careal scale factor ( currently 1.5) Dshear scale factor ( currently 3) g0u0g1u1g2u2g3u3g0u0g1u1g2u2g3u3 = cos2  0 sin2  0 1 cos2  1 sin2  1 1cos2  2 sin2  2 1cos2  3 sin2  3 C D D E nn + E ee E nn - E ee 2E en

Processed data are stored in XML format (ASCII). XML files are human and machine readable. Allows description of the data within the file. Provides reproducibility of the processed data Processed Strainmeter Data

JulAugSepOctNovDecJanFebMarAprMayJunJulAugSep B B B B a data 2b data

Processed Strainmeter Data JulAugSepOctNovDecJanFebMarAprMayJunJulAugSep B B B B B a data 2b data

Processed Strainmeter Data JulAugSepOctNovDecJanFebMarAprMayJunJulAugSep B B B B B B B B B B a data 2b data B

Processed Strainmeter Data PBO strain XML files contain, General strainmeter information Sensor information Processing information Processed data.

Processed Strainmeter Data T00:00: T23:55:00

Processed Strainmeter Data The most recent XML file is named BBBB.YYYY.xml.bz2 (enables download via cron) Flat ASCII version of most recent processed data set available from UNAVCO