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PBO BOREHOLE STRAINMETERS
SPECIAL INTEREST GROUP UNAVCO SCIENCE MEETING
14-16 MARCH 2006
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UNAVCO-PBO BSM • EngineersDave MencinMike HastingBob MuellerTim Dittman Wade Johnson Ryan McClimentJames StairSarah VenatorWarren Gallagher (network)
• Data Greg Anderson Jim Wright Kathleen Hodgkinson
• PermittingKyle Bohnenstiehl
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Olympic Peninsula
June-July 2005
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VancouverIsland
September 2005
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Oregon
Jan - Feb 2006
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Target region Total Priority
Olympic Peninsula 6 1
Vancouver Island 4 1
Tacoma 8 2
Portland 8 2
Anza 7 2
Central Oregon 8 2
S Oregon 7 8
Parkfield/Cholame 13 2
San Juan Bautista 8 3
Mendocino 7 3
SF Bay Area 8 3
Pinion Flat 1 2
Yellowstone 5 2
Mt. St. Helens 4 2
Long Valley 8 3
Mt. St. Helens 4 2
Total 103
Strainmeter Distribution
Permitted Strainmeters Sites
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Who decides what goes where?
The PBO Sitting Committee recommends how many strainmeters should be installed in particular regions of scientific interest.
PBO strainmeter engineers then find the best sites in those regions for installation.
Engineers examine:geological and topographic maps, air photos, satellite images and rock type.
Factors that must be considered:drill rig access, power, communications, permitting.
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120°120°120°120°
Gladwin Tensor Strainmeters
120°120°
90°30°
Cell cross section
Gage orientation
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Data Products
Level 0: Raw data from dataloggersData logger format, bottle, and miniSEED.
Digital counts.
Level 1: Raw data in geophysical unitsStrain, temperature, voltage ….
Level 2: Processed dataXML format
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Raw data
• 1-sps and 20-sps strain downloaded at hourly intervals from the GTSM21 datalogger.
• 1-sps data are converted to miniSEED and sent to the archives within 1 hour of arriving at Boulder
• Low frequency data are downloaded as day-long tar files. Unpacked, converted to miniSEED,sent to the archives within 1 hour of arriving at Boulder.
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Dataflow Boulder -> Archives and BSMAC
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Processing strainmeter data
Routine processing -> Level 2a products
• inspection of 100% of all 1-sps data• linearization• decimation to 300 second interval• editing• generate areal and shear strain• generation of time series corrections
• borehole effects• atmospheric pressure correction• tidal correction
• products no more than 14 days out of date
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Post processing -> Level 2b Products
• entire data set reprocessed every 3 months• recalculate:
• the tidal signal • atmospheric pressure response coefficients, • borehole relaxation, grout curing trends
• opportunity to review earlier edits• no more than 4 months out-of-date.
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Decimation
• decimate from 1-sps to 300 sec interval• a multi-stage decimation process • decimate by 2, 3 and 5 minimum phase causal filters.
M6.7 Baja, Mexico, 4 January 2006.Floe Quarry (P403)
Unfiltered 1-sps strain , gage1
Black line shows the filtered but undecimated data.
The red crosses are the 300 second data points.
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Comparison of 10 min and 5 min data
B009 1 Jan 2006
10 Min5 Min1-sps
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Measured tides
Calculate the tidal signal and atm pressure response using BAYTAP-G
Theoretical tides
Some Programs for Ocean Tide Loading (SPOTL).TOPOX 6.2, regional model for Straits of Georgia and Juan de Fuca.
-0.12
-0.1
-0.08
-0.06
-0.04
-0.02
0
Feb/12/2006 Feb/16/2006 Feb/20/2006
strain - trendstrain - trend - tide
-0.12
-0.1
-0.08
-0.06
-0.04
-0.02
0
Feb/12/2006 Feb/16/2006 Feb/20/2006
strain - trend - tidestrain - tide - atm pressure
P403
P403
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Borehole trends
Assume exponential plus linear terms y = F+A1*exp(T1*t)+M*t+A2*exp(T2*t)
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
2005/7/1 2005/9/1 2005/11/1 2006/1/1
CH0 RESIDUAL
CH1 RESIDUAL
CH2 RESIDUAL
CH3 RESIDUAL
-40
-30
-20
-10
0
10
20
2005/7/1 2005/9/1 2005/11/1 2006/1/1
B004 HOKOFALLS
CH0
CH1
CH2
CH3
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Generation of areal and shear strain
ui gauge readingsgi gauge weightings orientation matrixT topography matrix
u1u2u3u4
⎡
⎣
⎢⎢⎢⎢
⎤
⎦
⎥⎥⎥⎥
4x1
=
1/ g1 0 0 00 1 / g2 0 00 0 1 / g3 00 0 0 1 / g4
⎡
⎣
⎢⎢⎢⎢
⎤
⎦
⎥⎥⎥⎥
4x4
12
cos21
2sin21
212
cos22
2sin22
212
cos23
2sin23
212
cos24
2sin24
2
⎡
⎣
⎢⎢⎢⎢⎢⎢⎢⎢⎢
⎤
⎦
⎥⎥⎥⎥⎥⎥⎥⎥⎥
4x3
C 0 00 D 00 0 D
⎡
⎣
⎢⎢⎢
⎤
⎦
⎥⎥⎥
3x3
T[ ]3x3
εEE +εNN
εEE −εNN
2εEN
⎡
⎣
⎢⎢⎢
⎤
⎦
⎥⎥⎥
R
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First results
• Nine out of ten strainmeters sending data to archives• All drawing tides• All recording an accumulation of strain some unusual trends, B011
• All measuring microseisms
-40
-30
-20
-10
0
10
20
2005/7/1 2005/9/1 2005/11/1 2006/1/1
B004 HOKOFALLS
CH0
CH1
CH2
CH3
-25
-20
-15
-10
-5
0
5
2005/10/1 2005/11/1 2005/12/1 2006/1/1
B011 PGC3
CH0
CH1
CH2
CH3
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First results
• Pumping at one strainmeter, B001, Goldbeck
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Bridging the spectrum of crustal deformation
0
2
4
6
8
10
12
14
0
30
60
90
120
210
240
270
300
330
M2 AMPLITUDE (NANOSTRAIN)
CH0
CH1
CH2
CH3
DEGREES
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How can I get the data?
All data, raw and processed are stored at NCEDC and the IRIS DMC.
The PBO strainmeter data products page provides links.
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IRIS DMC and NCEDC
• Bottle files in ftp directory
• Seed data in a fully managed archive.
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SeismiQuery
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Buffer of Uniform Data BUD
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BUD
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M6.7 Baja, Mexico,
4 Jan 2006
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VASE
http://dmc.iris.washington.edu/manuals/vase.htm
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PQLII
ftp://ftp.passcal.nmt.edu/passcal/software/osX/pqlI
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XML Format
Processed data are stored in XML format.
XML files contain• General strainmeter information• Sensor information• Processing information• Processed data
XML files are archived in year-long files at NCEDC and IRIS DMC.
Filename conventionB004.2005.2005310144810
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XML Format
1 XML file contains 1 year of data
The current year will grow throughout the year• 2a data• no more than 14 days out of date .
Every 3 months the entire data set is reprocessed from time of installation
• 2b data• borehole, tides and response coefficients updated•XML files written for entire instrument life time, e.g.,
B004.2005.2006013043405B004.2006.2006013043405
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<station_information><site_name>FloeQuarry</site_name><station_long>floequary_p403_floe_quarry_....…</station_long>
<station_short>FloeQuaryBWA2005</station_short><dot_number>P403</dot_number><geocode>E4T1T9U2V1W4</geocode> <itype>BSM_</itype>
<model>GTSM21</model> <institution>PBO_UNAVCO</institution> <region>WA</region> <install_date>2005-06-23</install_date> <coordinate kind="station" ellipsoid="WGS84">
<lat>48.062360</lat><long>-124.140860</long><height units="m">314.00</height>
</coordinate> <minicluster_stations> </minicluster_stations> <time_zone>UTC</time_zone> <SEED> <site>P403</site> <network>PB</network> </SEED></station_information>
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<sensor_response> <sensor_start_date>2005-06-23T00:00:00</sensor_start_date> <sensor_end_date>Present</sensor_end_date> <sensor_type>Gladwin_BSM_component_1_</sensor_type> <sensor_code>E4T1T9U2V1W4+BSM_+Gladwin..…..</sensor_code> <channel_code>Gladwin_BSM_component_1_+00086400</channel_code> <depth units="m">169.80</depth> <orientation direction="east_of_north" units="degrees">250.7</orientation> <sensor_volts_per_unit> </sensor_volts_per_unit> <digitizer_counts_per_volt> </digitizer_counts_per_volt> <scalefactor_units_per_count unit="nstrain" kind="manufacturer">
0.1</scalefactor_units_per_count> <voltage_input_to_logger> </voltage_input_to_logger> <assigned_logger_bits> </assigned_logger_bits> <datalogger_manufacturer>GTSM Technologies</datalogger_manufacturer> <datalogger_serial_number>PBO-05-002</datalogger_serial_number> <datalogger_model>GTSM21</datalogger_model> <sensor_serial_number>PBO-05-002</sensor_serial_number> <response> </response></sensor_response>
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<bsm_processing> <timeseries_start_date>2005-06-23T00:00:00</timeseries_start_date> <timeseries_end_date>2006-02-19T23:55:00</timeseries_end_date> <linearization> … </linearization> <gage_weightings> … </gage_weightings> <orientation_matrix> … </orientation_matrix> <areal_and_shear_factors> … </areal_and_shear_factors> <topography> … </topography> <atm_pressure unit="microstrain_per_millibar"> … </atm_pressure> <tidal_parameters> … </tidal_parameters> <detrend_g0 units="microstrain" model="F+A1*exp(T1*t)+M*t+A2*exp(T2*t)"> <detrend_g1 units="microstrain" model="F+A1*exp(T1*t)+M*t+A2*exp(T2*t)"> <detrend_g2 units="microstrain" model="F+A1*exp(T1*t)+M*t+A2*exp(T2*t)"> <detrend_g3 units="microstrain" model="F+A1*exp(T1*t)+M*t+A2*exp(T2*t)"> <decimate_by_two_filter kind="causal" number="30"> …</decimate_by_two_filter> <decimate_by_three_filter kind="causal” number="23">…</decimate_by_three_filter> <decimate_by_five_filter kind="causal” number="34"> … </decimate_by_five_filter> </bsm_processing>
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<obs strain=”gage0"> <date>2006-02-19T23:50:00</date> <doy>50</doy>
<MJD>53785.993056</MJD> <s> 25.6272</s> <s_offset> 0.0019</s_offset> <s_q>g</s_q> <tc> 0.0012</tc> <dtc> 27.9551</dtc> <apc>999999</apc> <apc_q>m</apc_q> <v>2006053033413</v> <level>2a</level></obs>
MJD = Modified Julian dates = strains_offset = strain offsets_q = strain qualitytc = tide correctiondtc = detrend correctionapc = atm pressure correctionapc_q = atm pressure qualityv = version
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How do I read the XML files?PBO provides an XML reader rdstrain.xml
• extract XML header information only• print strainmeter summary information only • output format (tab delimited ASCII or XML) • replace bad or missing strain data with a specified flag• replace bad or missing atm correction data with a specified flag• specify a window of time
Produces ASCII versions of each componentxml_filename.gage0xml_filename.gage1xml_filename.gage2xml_filename.gage3xml_filename.Eee+Ennxml_filename.Eee+Ennxml_filename.2Ene
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ASCII version"gage0" 2006-01-01T00:00:00 1 53736.000000 -33.4729 0.0 g -0.015 -33.345 0.094 g 2a"gage0" 2006-01-01T00:05:00 1 53736.003472 -33.4727 0.0 g -0.014 -33.346 0.094 i 2a "gage0" 2006-01-01T00:10:00 1 53736.006944 -33.4726 0.0 g -0.013 -33.346 0.093 i 2a
• Strain description, gage0, Eee+Enn, • date date ISO format• doy day of year• MJD Modified Julian Date• gage0(Microstrain) linearized strain• s_offset strain offset • strain_quality g,b,m,I• tide_c tidal correction• detrend_c detrend correction• atmp_c atmospheric pressure correction• atmp_c_quality atmospheric pressure quality• level 2a, 2b• version version number
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Future Development
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Future Development
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IRIS Uniform Product Distribution System
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Strainmeter WorkshopUNAVCO
BOULDER14-16 June 2006