(IRIS-PASSCAL) Foundations of Portable Seismology: The Program for Array Seismic Studies of the Continental Lithosphere - Anne Sheehan, University ...
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Foundations of Portable Seismology:
The Program for Array Seismic Studies
of the Continental Lithosphere
(IRIS-PASSCAL)
Anne Sheehan, University of Colorado Boulder
IRIS Workshop 2018
Outline • Field Seismology Before PASSCAL • Origins of PASSCAL • Early PASSCAL experiments • PASSCAL Science (a small sampling!)
Sierra Nevada, CA, 1988, Anne Sheehan (Craig Jones Photo)
Field Seismology in the 1980’s –
still using helicorders for some experiments
Utah 1983, Denis Hatzfeld (Craig Jones Photo)
Sierra Nevada 1988, Tom Fairbanks (Craig Jones Photo)
Photo credit: Craig Jones Photo credit: Craig Jones
Field Seismology in the 1980’s –
Assortment of digital recording
Varying formats
Data not usually shared, archiving ad hoc
Limited recording capacity (event triggered)
Late 1970’s and Early 1980’s - Reports from the National
Academy helped lead to the development of the IRIS
Consortium
1983
1983
1983
1977
The Original IRIS Proposal to NSF
(the ‘Rainbow Proposal’)
December, 1984
1984 IRIS ‘Rainbow’ Proposal
Proposal for a ten-year program for the implementation of four major
national facilities for seismology:
• A Global Digital Seismic Array
featuring real-time satellite telemetry from one hundred modern
seismographic observatories
• A Mobile Array
comprised of one thousand portable digital seismographs to be used for
studies of the continental lithosphere
• Central Data Management and Distribution Facilities
to provide rapid and convenient access to the data sets for the entire
research community
• A Major Computational Facility
capable of supporting the analyses of these new data
The PASSCAL program was an important Eos, Vol. 67, No. 16, April 22, 1986
1984 part of the original IRIS Proposal Masters, G., T . J o r d a n , P. Silver, a n d F. Gil-
bert, Aspherical earth structure f r o m fun-
damental spheroidal m o d e data, Nature,
Nakanishi, I., a n d H . Kanamori, Source
mechanisms o f twenty-six large, shallow
Riedesel, M., D . A g n e w , J. Berger, a n d F.
Gilbert, Stacking for the frequencies a n d
earthquakes (M 2* 6.5) d u r i n g 1980 from
s Qs o f QSO a n d \So, Geophys. J. R. Astron. Soc,
298, 6 0 9 , 1 9 8 2 . P-wave first m o t i o n and long-period Ray- 62, 4 5 7 , 1980.
Masters, G., J. Park, an d F. Gilbert, Observa- leigh wave data, Bull. Seismol. Soc Am., 74, Romanowicz, B., M. Cara, I. F. Fels, a n d D .
tions o f c o u p l e d spheroidal a n d toroidal 8 0 5 , 1984. Rouland, G E O S C O P E : A French initiative
m o d e l s , / . Geophys. Res., 88, 10285, 1 9 8 3 . Nataf, H . - C , I. Nakanishi, a n d D . L. A n d e r - in long-period t h r e e - c o m p o n e n t global seis-
Nakanishi, I., a n d D . L. A n d e r s o n , World- son, Anisotropy a n d shear velocity hetero- mic networks, Eos Trans. AGU, 65, 7 5 3 ,
wide distribution o f g r o u p velocity o f man- geneities in t h e u p p e r mantle, Geophys. Res., 1984.
tle Rayleigh waves as d e t e r m i n e d by spheri- Lett., 11, 109, 1 9 8 4 . Savino, J. K., K. McCamy, and G. H a d e ,
cal harmonic inversion, Bull. Seismol. Soc. Niazi, N . , and H. Kanamori, Source parame- Structures in earth noise b e y o n d twenty
Am., 72, 1185, 1982. ters o f 1978 Tabas and 1979 Qainat, Iran, seconds, a w i n d o w for earthquakes, Bull.
Nakanishi, I., a n d D . L. A n d e r s o n , Measure- earthquakes from long-perio d surface Seismol. Soc. Am., 62, 141, 1972.
ments o f mantle wave velocities a n d inver- waves, Bull. Seismol. Soc. Am., 71, 1 2 0 1 , T a n i m o t o , T . , a n d D . L. A n d e r s o n , M a p p i n g
sion for lateral heterogeneity and anisotro- 1981. convection in the mantle, Geophys. Res. Lett.,
py, 1, Analysis o f great circle phase veloci- Okal, E., a n d L. Stewart, A negative search 11, 2 8 7 , 1984.
t i e s , / . Geophys. Res., 88, 10267, 1 9 8 3 . for an ultra-slow c o m p o n e n t to the source T a n i m o t o , T., a n d D . L. A n d e r s o n , Lateral
Nakanishi, I., a n d D . L. A n d e r s o n , Measure- o f the Y u n n a n earthquakes o f May 29, heterogeneity a n d azimuthal anisotropy o f
ments o f mantle wave velocities a n d inver- 1976, Phys. Earth Planet. Inter., 26, 2 0 8 , the u p p e r mantle: Love and Rayleigh
sion for lateral heterogeneity and anisotro- 1981. waves 2 0 0 - 2 5 0 s,J. Geophys. Res., 9 0 , 1 8 4 2 ,
py, 2, Analysis by the single-station m e t h - Parker, E. B., Micro earth stations as personal 1985.
o d , Geophys. J. R. Astron. Soc, 78, 5 7 3 , c o m p u t e r accessories, Proc IEEE, 72, 1526, W o o d h o u s e , J., a n d A. Dziewonski, M a p p i n g
1984a. 1984. the u p p e r mantle: T h r e e - d i m e n s i o n a l m o d -
Nakanishi, I., a n d D. L. A n d e r s o n , Aspheri- Peterson, J., a n d E. E. Tilgner, Description eling o f earth structure by inversion o f seis-
cal heterogeneity o f the mantle from phase and preliminary testing o f t h e C D S N seis- mic w a v e f o r m s , / . Geophys. Res., 89, 5 9 5 3 ,
velocities o f mantle waves, Nature, 307, 117, mic sensor system, U.S. Geol. Surv. Open File 1984.
19846. Rep. 85-288, 1985.
IRIS: A Program
T h e 1986 A G U Spring Meeting marks the
first anniversary in the operational life o f the
IRIS Consortium. It was a year a g o that plan-
n i n g funds b e c a me available from the Nation-
for the Next Decade
PAGES 213-219
al Science Foundation (NSF) so that commit-
tee work could begin t o b e translated into ac-
tion. It was also the first time that hard
choices about allocation o f limited resources
a m o n g c o m p e t i n g programs were faced. T h i s
Stewart W. Smith report reviews the early experience in the o p -
Incorporated Research Institutions eration o f the consortium and the specific
for Seismology, Arlington, Va. progress that has b e e n m a d e d u r i n g the past
year toward o u r long-range goals.
The Incorporated Research Institutions for Seismology (IRIS) Consortium has
produced an ambitious plan for new seismological research facilities to be devel-
The Current IRIS Program
oped during the coming decade. The plan reflects a broad consensus among seis-
mologists in this country with respect to both the need for improved data and the Until October 1985, the physical existence
o f IRIS was limited to a mail d r o p at the
potential for significant scientific advances that can occur as a result. The three A G U headquarters building in Washington,
elements of this program are a 100-station broadband global network utilizing D.C., a c o n v e n i e n ce for which we are grate-
satellite telemetry, a 1000-station portable network of advanced digital seismo- ful, and an electronic mail system that linked
key members o f committees across t h e coun -
graphs, and a national center for management and distribution of the data gen- try. Without the latter it is difficult to imagine
erated by these networks to the research community. The purpose of this paper h o w the enterprise could have functioned
is to provide a brief overview of the long-range plan and an update as to the pro- d u r i n g those early days. Space was leased,
furnished, and o c c u p i e d durin g October
gress made to date. 1985; a small staff was assembled to begin o p -
erations at that time.
IRIS represents t h e first attempt by seis-
Introduction research tools. T h e tools, or national facilities,
will serve the earth sciences as primary data
mologists (of the dry land variety, anyway) to
organize and operate such a consortium.
In a major departure from the traditional sources well into the next century. Replace- T h e r e are, o f course, a n u m b e r o f successful
Smith,
single-investigator approach to research sup- m e n t o f the present vintage e q u i p m e n t with precedents in other disciplines to u se as m o d -
port, the seismological c o m m u n i t y c a m e to- m o d e r n instrumentation a n d data manage - els, such as the University Consortiu m for At-
gether in 1984 in a national grassroots move- m e n t systems is a necessary step in achieving mospheric Research (UCAR) a n d t h e Joint
m e n t to create a consortium o f research uni- a major i m p r o v e m e n t in o u r ability to under- Oceanographic Institutions (JOI). A s new-
EOS, 1986
versities for the p u r p o s e o f i m p l e m e n t i n g, stand the earth's interior. comers to this style o f operation, w e are just
t h r o u g h a cooperative approach including in- O u r k n o w l e d g e o f the earth's interior is b e g i n n i n g to learn the kinds o f things that
dustry a n d g o v e r n m e n t agencies, a set o f ini- now limited by data quality a n d quantity. are necessary to make it successful. A s ex-
tiatives for critically n e e d e d national facilities T h e o r y a n d analysis techniques exist to im- pected, o n e o f the keys has b e e n the sublima-
necessary to support seismological research in prove o u r view o f t h e subsurface substantial- tion o f specific institutional a n d individual
the c o m i n g decades. IRIS, the Incorporated ly, b e y o n d the thin skin accessible to the drill. priorities in o r d e r to p r o m o t e the larger goals
Research Institutions for Seismology, a n o n - Important questions in geodynamics, re- o f IRIS. T h a t this s e e m s to work is a result o f
profit corporation, was f o u n d e d May 8, 1984. sources, a n d geological hazards d e m a n d this the widespread effort that went into t h e early
T h e IRIS proposal [McEvilly and Alexander, i m p r o v e d u n d e r s t a n d i ng o f o u r earth. T h i s planning an d d e v e l o p m e n t o f the science
1984] that e m e r g e d from this effort repre- IRIS p r o g r a m will provide the n e x t genera- plans [IRIS, 1984a,b]. With scientific goals
sented the collective request from the U.S. tion o f geophysicists with the m e a n s to ad- a n d priorities so generally agreed u p o n in ad-
seismological c o m m u n i t y for a set o f m o d e r n dress these questions. vance, the d e v e l o p m e n t o f priorities for spe-
0096-3941/86/6716-0213$ 1.00
Copyright 1986 by the American Geophysical Union
ork the China Digital Seismograp h Network this
year, as well as f r o m the u p g r a d e d IRIS sta-
1984tions, clearly calls for r e v a m p i n g the existing Portable Array Studies
data collection and processing system. Buland (PASSCAL)
[1985] has d e v e l o p e d a plan for a m o d u l a r
for u p g r a d i n g system that should permit both a significant Instrument Development
ers in 1986 increase in the v o l u m e o f data and a s m o o t h
gital World- transition to the n e w system with m i n i m u m T h e P A S S C A L Science Plan spelled out in
etwork d o w n time. His plan is for a local area net ap- detail the n e e d for an advanced portable seis-
ata l o g g i ng fa- proach, based o n a system o f 32-bit micro- m o g r a p h system. T h i s system w o u l d be digi-
r a d e can be processors. In o r d e r to minimize labor-inten- tal, with h i g h d y n a m ic range; it w o u l d be
tions to the sive tape handling, e n o u g h mass storage to portable and m i c r o - p o w e r e d, a n d most im-
al sensors at k e e p all active data on-line will be required. portantly, it w o u l d be flexible a n d m o d u l a r so
mal analog re- IRIS and U S G S are p r o c e e d i n g jointly to as to be able to adapt to c h a n g e s in technolo-
able, systems c o m p l e t e this n e w m o d u l a r data collection gy that are likely to occur over the lifetime o f
e visible re- center d u r i n g 1986, with IRIS providing the the instrument. Since the plan is to make a
o f these fa- necessary hardware and U S G S providing the major national c o m m i t m e n t t h r o u g h the pur-
be provided. p e r s o n n e l and software. chase o f 1000 instruments, it is clear that we
RIS and im- should not freeze in place the technology
(N.M.) Seis- available at this particular point in history.
Telemetry
logical Survey T h e rapidly c h a n g i n g field o f mass storage il-
are Afiamalu A progra m for evaluation o f global teleme- lustrates the most obvious e x a m p l e o f this
n), Kevo (Fin- try options for IRIS has b e e n u n d e r w ay at problem, but comparable c h a n g e s in e n c o d e r
ege (Alaska). Smith,
the Stanford Satellite C o m m u n i c a t i o ns Plan- technology, timing systems, a n d virtually ev-
ery other part o f the system are very likely
EOS, 1986
n i n g Center a n d at U C S D for the past year.
Researchers there have e x p e r i m e n t e d with an over the n e x t decade. T o avoid this, a plan
economical low-power system that uses the was m a d e for a m o d u l a r communication s
rnational D e - "spread spectrum" technique, i m p l e m e n t e d "bus" approach to design. With this concep t
this issue (p. by Equatorial Communications , Inc. ( M o u n - the seismic instrumen t functions as a local
1984
Photo from PASSCAL web page
Jim Fowler, founding manager
Photo credit: Craig Jones for PASSCAL program. Started
Bob Phinney, First chair of as IRIS Chief Engineer in 1984.
PASSCAL Standing CommitteePASSCAL Timeline 1984 – IRIS Incorporated 1991 – Tibet broadband experiment (1st BB 1986 – Ouachita Experiment experiment to produce SEED data) 1986 – Basin and Range Experiment 1991 – Stanford PASSCAL instrument center 1986 – Issue RFP for new instrument established – active source and RAMP 1987 – Issue contract to develop a new 1992 – Rocky Mountain Front experiment – first instrument experiment with over 25 broadband 1988 – Basin&Range Passive Experiment 1995 – first GPS clocks on REF TEKs - 1st experiment with prototype 1998 – New PASSCAL Instrument Center at New instruments. Mexico Tech, closed LDEO and Stanford 1989 – First PASSCAL instrument center instrument centers opened at Lamont 1999 – first TEXAN instrument 1989 – Loma Prieta – first aftershock 2002 – new data acquisition systems developed deployment (RAMP) 2003 – USArray starts 1990 – receive first broadband sensors
PASSCAL Oachita Experiment, 1986
400 seismic group recorders (SGR) from Amoco. Each recorded
data from a string of geophones on digital cassettes. Overlapped
Keller et al, Geology, 1989
COCORP line.PASSCAL Basin and Range, 1986 & 1988
Randall and Owens, 1994
Catchings et al, 1988Lamont PASSCAL Instrument Center (PIC), 1989 - 1998
http://www.columbia.edu/cu/record/archi
Photo credit: Bob Busby ves/vol20/vol20_iss19/record2019.21c.gif
Art Lerner-Lam Noel Barstow
Bob Busby Paul Friberg
Photo credit: Bob Busby
Photo credit: Bob BusbyLoma Prieta 1989 – 1st RAMP (aftershock) deployment
Heidi Houston, Thorne Lay, Susan Schwartz, - This was the second overall deployment
David Simpson and Ornella Bonamassa of the new PASSCAL equipment.
deploying PASSCAL instruments. - Data collected in triggered mode using
STA/LTA. Photos from Susan SchwartzLoma Prieta 1989 – 1st RAMP (aftershock) deployment
1991 Stanford PASSCAL Instrument Center Established – Active Source and RAMP
Tibet – 1st major Broadband experiment 1991-92
Tom Owens and Francis Wu, PIs
Greg Wagner and Lupei Zhu 11 stations - 10 STS2, 1 Guralp CMG3-ESP
330 mb hard disks, data download by hard disk
or exabyte tape
Demonstrated that very high-quality broadband data Data stream 1 – 5 sps triggered, Data stream 2
could be obtained at temporary sites in extreme – 40 sps triggered, Data stream 3 – 1 sps
environments. continuous
OMEGA clocks
Data of interest to scientists beyond the PIs on the
project Photo credits: Left, Francis Wu; Center Lupei Zhu.Tibet – 1st major Broadband experiment 1991-92
McNamara, Owens, Silver, Wu, JGR, 1994
McNamara, Walter, Owens, Ammon, JGR, 1997
Owens, Randall, Wu, Zeng, BSSA, 1993Rocky Mountain Front 1992. 30 Broadband stations
Lerner-Lam, Humphreys, Grand, PIs
Omega clocks, 200 mb disks, triggered and
Photo credits: Anne Sheehan low rate continuousRocky Mountain Front 1992. 30 Broadband stations
Lerner-Lam, Humphreys, Grand, PIs
Exabyte drive to download
data to exabyte tape in the
field. Epson controller for DAS.
Omega clocks, 200 mb disks, triggered and
Photo credits: Anne Sheehan low rate continuousRocky Mountain Front 1992. 30 Broadband stations
Found Rockies are not compensated by a simple Airy-type root, require significant
compensation in the mantle
Mantle structure from teleseismic S-wave tomography
Crustal thickness from receiver functions
Sheehan, Abers, Lerner-Lam, Jones, JGR, 1995
Lee and Grand, JGR, 19961993 Cascadia Experiment
PI Nabelek, OSU
69 broadband sites
44 stations simultaneously
Spacing 4 km
Nabelek et al., One-pager from IRIS Proposal, 1995
Li and Nabelek, 19991993 Cascadia Experiment Image of Cascadia Subduction zone from
teleseismic converted phases
PI Nabelek, OSU
69 broadband sites
44 stations simultaneously
Spacing 4 km
Nabelek et al., One-pager from IRIS Proposal, 1995
Li and Nabelek, 19991993 Cascadia Experiment Scattered wave image
PI Nabelek, OSU
Thermal model
69 broadband sites The loss of signal
44 stations simultaneously from the continental
Moho in the mantle
Spacing 4 km forearc is attributed to
mantle
serpentinization by
fluids released from
the subducting plate.
Bostock et al., 20021998 New Mexico Tech PASSCAL Instrument Center Established Mission: Provide state-of-the-art, low power portable seismic instrumentation and deliver basic field expertise and data management tools in support of portable array seismic experiments worldwide
BEAAR, Alaska. 1999-2001. HIMNT, Nepal-Tibet. 2001-2002.
Abers, Christensen, Hansen Sheehan, Wu, Bilham
Dehydration
reactions explain
changes in seismic
velocities seen
within subducting
Attenuation crust
Tomography
Decollement
at base of
the Himalaya
Abers et al., EPSL 2006 Schulte-Pelkum et al., 2005Studies of the Earth’s inner core using PASSCAL data from BOLIVAR (Venezuela) Niu and Chen, Nature Geo, 2008 Miller and Niu, EPSL, 2008
Details of Tremor Observed by a Dense Seismic Array Ghosh, A., J. E. Vidale, J. R. Sweet, K. C. Creager, A. G. Wech, and H. Houston (2010), Tremor bands sweep Cascadia, Geophys. Res. Lett., 37, L08301.
PASSCAL Today 46 different experiments in 2017 48 different experiments in 2018 Examples of 2017/18 experiments – Mexico RAMP Alaska Amphibious Array Education – Geophysics classes Totten Glacier Rutford Ice Stream Induced seismicity – CO, TX, OK Patagonia Mongolia SHIRE New Zealand Seismic study of post-fire flash floods FLUME 2.0 Dead Sea wide angle
Summary – PASSCAL has allowed us to do research on tectonic process on every continent, at every type of plate boundary, and a tremendously broad range of scales. Much of what we now know about collisional processes in orogens, modes of rifting, and the cycling of melt and volatiles in subduction zones comes from PASSCAL experiments. PASSCAL is guided by the community to address the major seismological science targets of today and tomorrow, even as those targets become more broad in nature.
Thank you to the many people who provided
slides and information!
• Francis Wu • Paul Passmore
• Bob Busby • Tom Owens
• Susan Schwartz • Karen Fischer
• Randy Keller • Steve Roecker
• Steve Harder • Craig Jones
• Susan Beck • Peter Molnar
• Ken Creager • Kent Anderson
• Lara Wagner • Bob Woodward
• Art Lerner-Lam • Marcos AlvarezPASSCAL Inventory, 2018
Highlights: Calendar Quarter 1, 2018
SAGE, GLISN, & GEOICE: FY18, Y5, Q2
Equipment Inventory as of March 31, 2018
Table 6: Equipment inventory at the end of Q1, 2018
Inventory Data loggers All-in-one Sensors
MC Geophone 1-ch
3-Ch/Broadband
3-Ch Data logger
6-Ch Data logger
3-Ch/Geophone
Geophone 3-ch
Geophone 1-ch
Accelerometer
1-Ch “ Texan”
Multi-Channel
Intermediate
Short Period
Broadband
PASSCAL 1221 81 2185 17 73 782 17 319 829 2416 817 30
RAMP 10 10 10
Polar 71 6 128 2 3
GLISN 14 10
GEOICE 65 200 65
TA 312 142 559 82
Total 1669 253 2185 17 273 1544 29 319 829 2416 817 125You can also read
