Transcript Portable Broadband Seismology Part 2: Functions of an Instrument Center Jakarta, Indonesia

Portable Broadband
Seismology
Part 2: Functions of an Instrument Center
Jakarta, Indonesia
May 11-13, 2006
Bruce Beaudoin
Marcos Alvarez
PASSCAL
Program for Array Seismic
Studies of the Continental
Lithosphere
Outline
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Facility overview
Equipment Supported
Experiments Supported
Inventory
Equipment Maintenance and QC
User Services
Polar Support
PASSCAL
A facility for academic
research in seismology.
Funded by the National
Science Foundation and the
Department of Energy.
Instrument Use
• Available to researchers for non-commercial
use
• PI must agree to the following conditions
– All data must be released to the IRIS Data
Management center within 2 years of completion
of field work
– PI must receive proper training at the Instrument
Center
– PI responsible for all shipping and customs cost
PASSCAL Facilities: Core
• PASSCAL Instrument Center, Socorro
– Main support and development
– 13.5 FTEs
• Active Source Support Center, UTEP
– Use of 400 instruments and field support
– 1.5 FTEs
• Telemetered Array Support Center, UCSD
– Telemetry support for field experiments
– 1.5 FTEs
PASSCAL Facilities: AOF
• Array Operations Facility at PASSCAL
Instrument Center, Socorro
– Main support and development for
USArray Transportable and Flexible
Arrays
– 9.5 FTEs
• Transportable Array Coordinating Office
– Field logistics support for TA
– 4 FTEs
Equipment
Inventory
Item
Current
Reftek R130
460
Quanterra Q330
370
Multi-channel
4
Texans (125)
828*
Texans (125A)
150
Broadband Sensor
439
Short Period Sensor
264
High Frequency Sensor
419
06
4
22
Equipment Inventory:
3-channel dataloggers
Quanterra Q330
RefTek RT130
Equipment Inventory:
1-channel datalogger
RefTek RT125
Equipment Inventory:
Seismometers
Sensor
Manufacturer
STS-2
Streckeisen
CMG-3T
CMG3ESP
CMG40T
Gura lp
Gura lp
Power
50 ma @
12vdc
100 ma @
12vdc
100 ma @
12vdc
50 ma @
12vdc
S-13
Gura lp
Teledyne
Geotech
L-4C
Mark Products
passive
L-22
Mark Products
passive
L-28
Mark Products
passive
L-40
Mark Products
passive
passive
Natural
Frequency Damping
0.707
0.0083 Hz critical
0.707
0.0083 Hz critical
.707
0.033 Hz
critical
0.707
0.033 Hz
critical
0.707
critical
1.0 Hz
0.707
critical
1.0 Hz
0.707
critical
2.0 Hz
0.707
critical
4.5 Hz
0.707
40 Hz
critical
Sensitivity
1500 v/m/s
1500 v/m/s
2000 v/m/s
800 v/m/s
629 v/m/s
166.54
v/m/s
88 v/m/s
30.4 v/m/s
22.34 v/m/s
Equipment Inventory:
Broadband Seismometers
Guralp CMG-3T
Streckeisen STS-2
Equipment Inventory:
Intermediate Period
Seismometers
CMG-40T
30s active feedback
CMG-ESP
30s active feedback
Equipment Inventory:
Short Period Seismometers
L4C
1Hz
Teledyne GS-13
1Hz
1 Element/Housing
L22
2Hz
Passive Sensors
Equipment Inventory:
High Frequency
Seismometers
L28
L40 Strings
4.5 to 40Hz
Single component
Strings of single component
3-Component
Seismic Experiments
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Utilize sound waves propagating
through the earth to create images of
the earth’s bulk properties (e.g.
velocity, attenuation, travel-time
anomalies).
Two basic sources for sound waves:
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Passive (natural sources).
Active Source (man made).
Experiment Support
Experiment Type
Number for 2006
Broadband
25
Short Period
15
RT125 (Active Source)
6
Multi-channel
6
Total
52
Characteristics of a
Passive Experiment
• Sources include: earthquakes, ambient
noise, tides, magma.
• Long term (months to years)
• Broad spacing (regional to global)
• Low frequency (.001-1Hz)
• Typically a few to tens of instruments.
Sources for Passive
Experiments
Broadband Stations
Since 2000
Namche Barwa, Tibet
Meltzer, Sol, Zurek, Zeitler
Receiver functions
indicate the thinnest
crust is associated
with the region of
highest exhumation.
Shear wave splitting
indicates a fast
direction consistent
with surface tectonic
features. Authors
argue for a strong
lower crust.
May 10, 2003 Eruption of Anatahan
Volcano, Mariana Islands
• PASSCAL station
installed 4 days prior to
eruption
• Volcano-tectonic events
start to occur 5 hrs
before eruption and
significantly increase 1
hrs prior.
• Tilt is reconstructed
from STS-2 horizontal
signal
Pozgay & Wiens
Active Source
Experiments
• Sources include: explosions, airguns,
sledge hammers, vibrators
• Short term (days to weeks)
• High frequency (2-80+Hz)
• Hundreds of instruments
• Closely spaced
Some Sources
Celebration 2000
Keller et al.
147 Shots
1230 Stations
5400 km
Hill Air Force Base, Utah
Gao et al.
RAMP
Rapid Array Mobilization Policy
2002 Denali 7.9M, over 30,000 aftershocks recorded
Ruppert et al.
Inventory Database
• PASSCAL maintains an extensive inventory
of all equipment
• The inventory provides two main purposes
– Instrument tracking
– Maintenance history
• All equipment is barcoded and entered into an
in-house developed database driven by mysql
PASSCAL Inventory &
Maintenance database
Interface for searching inventory
PASSCAL Inventory &
Maintenance database
Tracks shipments by experiment code
PASSCAL Inventory &
Maintenance database
Tracks inventory items assigned to experiments
PASSCAL Inventory &
Maintenance database
Maintenance records
Hardware Maintenance and
QC: Dataloggers
Function test all DAS prior to
shipment
Maintain maintenance records in an
electronic database
Test and upgrade firmware when
necessary
Monitor DAS running in house for
unusual behavior
Hardware Maintenance and
QC: Seismometers
• All broadband seismometers are function tested when
they arrive from an experiment.
• All broadband seismometer are pier tested for 4-7 days
and the data are compared to a reference seismometer
prior to deployment.
• Comparisons are made of:
– Polarity
– Amplitude
– Power Spectral Density
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Typical problems include:
– pivot pings
– Sensitivity
– imbalanced masses
User Services
Data QC & Software
• PASSCAL develops and maintains
software to extract data from the
dataloggers, perform in-field quality
control, and manipulate the waveforms
into archive formats (SEGY, SEED).
• http://www.passcal.nmt.edu
• ftp.passcal.nmt.edu
Troubleshooting
• PASSCAL provides email and phone support
for our users both during and after their field
deployment. Staff are available to analyze
specific problems and frequently recognize
potential problems in our lab before they
manifest in-situ.
• Typically there are over 400 broadband and
short-period PASSCAL stations deployed at
any given time.
Data Archiving
Support
PASSCAL acts as an intermediary between
the PI and the DMC
Check completeness of data submitted to
PASSCAL
Flag waveforms w/ questionable timing
Fix mseed headers
Verify SEED Format
Ensure agreement between dataless and
waveforms
Check completeness of data submitted to
DMC
Data Delivery Services
PASSCAL’s Support of Polar
Research
Antarctic Experiment
Support
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~25 Experiments
supported since 1990
Most experiments are
multi-year (e.g overwinter)
2005-2006 supporting 6
Antarctic experiments
(62 stations + snow
streamer)
Broadband, activesource, glaciology
Equipment Limitations
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Q330 - Fully spec’d to -40C
Baler - -40C (not media)
Disk Drive - -20C
Flash Media - -55C
STS-2 0-40C
3T - -10C-65C,
cabling -20C
power controller -20C
Additional Resources
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Environmental Chamber - 27 cu. ft., -70C to
120C
60 - channel snow streamer
80’ takeouts, 7 12-takeout cables, Geode
adapters.
Solid state disks - 4 9 GB
Wind generators - 10