B921 randsb921bcs2008 Latitude 35.5865 Longitude -117.4622 Elevation 694.5 m Install Date 2008-06-03 Contents Of Tar files for year YYYY File Contents B921.YYYY.xml.gauge0.txt.gz Processed data from gauge 0 (CH0) B921.YYYY.xml.gauge1.txt.gz Processed data from gauge 1 (CH1) B921.YYYY.xml.gauge2.txt.gz Processed data from gauge 2 (CH2) B921.YYYY.xml.gauge3.txt.gz Processed data from gauge 3 (CH3) B921.YYYY.xml.Eee+Enn.txt.gz Processed areal strain, manufacturer's calibration B921.YYYY.xml.Eee-Enn.txt.gz Processed differential strain, manufacturer's calibration B921.YYYY.xml.2Ene.txt.gz Processed engineering shear strain, manufacturer's calibration some tars may contain the additional files B921.YYYY.xml.Eee+Enn.ER2010.txt.gz Processed areal strain, Roeloffs [2010], calibration B921.YYYY.xml.Eee-Enn.ER2010.txt.gz Processed differential strain, Roeloffs [2010], calibration B921.YYYY.xml.2Ene.ER2010.txt.gz Processed engineering shear strain, Roeloffs [2010], calibration Description of Level 2 Borehole Strainmeter ASCII files. Column 1 Description of data, gauge0, gauge1 etc Column 2 Date, YYYY-MM-DDTHH:mm:ss Column 3 Day of year Column 4 Modified Julian Date Column 5 Strain (microstrain). No offsets, trends, tides or barometric corrections have been applied. Column 6 Running sum of offsets Column 7 Strain data quality flag (g=good, b=bad, m=missing) Column 8 Tidal correction (microstrain) Column 9 Borehole trend correction (microstrain) Column 10 Barometric pressure correction (microstrain) Column 11 Barometric pressure data quality flag (g=good, b=bad, m=missing, i=interpolated) Column 12 Level, quality (2a= rapid processing, 2b=post processed) Column 13 Version, data generation date Column 14 Barometeric pressure (millibars) To produce strain data with offsets, tides, trends, tides and barometric pressure effect removed use Final_Strain=Column5+Column6-Column8-Column9-Column10 Processing Information Manufacturer: GTSM Technologies Manufacturer Gauge Scale Factor: 0.05 nanostrain per digital count Manufacturer Areal Scale Factor: 1.5 Manufacturer Shear Scale Factor: 3.0 Manufacturer Gauge Weightings: CH0=1, CH1=1, CH2=1, CH3=1 CH0 Orientation recorded in field = 340.5 degrees east of north Borehole Trend Models, calculated in days, y=F+A1*exp(T1*t)+M*t+A2*exp(T2*t) Gauge F A1 T1 M A2 T2 CH0 -81.070 44.485 -0.00089 0.00440 0.009 0.00189 CH1 -146.518 100.140 -0.00122 -0.01105 0.955 0.00053 CH2 -80.420 85.064 -0.00211 -0.02185 0.000 0.00000 CH3 -140.850 78.503 -0.00117 -0.00206 0.000 0.00000 Detrend reference date 2008-06-03T00:00:00 Barometric Response Gauge Response(ns/millibar) CH0 -2.8 CH1 -2.0 CH2 -2.4 CH3 -2.3 Tidal Constituents Gauge Tide Phase Amp(ns) CH0 M2 13.988 10.544 CH0 O1 -25.184 0.625 CH0 P1 -29.210 0.247 CH0 K1 -78.564 0.467 CH0 N2 9.844 2.048 CH0 S2 21.078 5.444 CH1 M2 54.014 1.838 CH1 O1 -31.495 2.190 CH1 P1 -30.515 1.074 CH1 K1 -31.392 2.830 CH1 N2 42.885 0.645 CH1 S2 103.949 0.976 CH2 M2 -16.256 7.350 CH2 O1 18.193 9.003 CH2 P1 16.824 3.842 CH2 K1 20.444 9.979 CH2 N2 -28.356 1.159 CH2 S2 -13.027 3.691 CH3 M2 -2.017 9.377 CH3 O1 22.365 5.447 CH3 P1 18.475 2.405 CH3 K1 25.540 5.592 CH3 N2 -10.721 1.531 CH3 S2 3.952 4.912 Strain Matrices To Compute Areal and Shear Strain from Gauge Strain Manufacturer's Isotropic Strain Matrix, C=1.5, D=3.0, Gauge Weights=1, Orientation = 340.5 ISOTROPIC 0.29629699 0.51851786 0.29629594 0.22222254 ISOTROPIC -0.20708728 0.34577170 0.06877857 -0.20746298 ISOTROPIC -0.33279091 -0.13272595 0.38588078 0.07963608 Hodgkinson et al. (2013) Tidal Calibration KH2013 0.841 1.555 0.7 0.333 KH2013 -0.521 0.362 0.296 -0.22 KH2013 -0.588 -0.977 0.219 0.171 Reference: Table 2. Hodgkinson, K., J. Langbein, B. Henderson, D. Mencin, and A. Borsa (2013), Tidal calibration of plate boundary observatory borehole strainmeters, J. Geophys. Res. Solid Earth, 118, 447–458, doi:10.1029/2012JB009651. Wed Dec 27 11:27:32 UTC-06:00 2023