IRIS PROJECT INITIATION FORM
PIF Ref:
Title:
Authors:
Date:
PIF-PA-2012-02
Active Source Seismology Initiative – Advancing Seismic Sources within IRIS
Lee Liberty, Katie Keranen, Ted Clarke, and Thomas Pratt
Original: 11 February 2011, Updated 5 April 2012
Project Description
During the past 27 years, seismology and our knowledge of Earth structure and processes have been
revolutionized by the availability of PASSCAL instrumentation and expertise. IRIS has facilitated
collaborative and community seismology programs including Earthscope and Polar Programs. In this
proposed initiative, we seek to expand the role of IRIS to infuse active-source seismology into a broader
range of seismic experiments to better understand the Earth processes targeted in the next generation
of ‘grand challenges’ championed by IRIS. We propose to integrate land-based active source expertise,
procedures, and equipment for use at a range of scales into the core PASSCAL mission.
We support an expanded role for land-based active sources within the seismological community by
integrating support for active sources of various types and sizes into the PASSCAL program. This
initiative includes developing a National Seismic Source (NSS) facility to provide expertise and training
for explosive shots aimed at imaging various levels within the crust or upper mantle via a subcontract to
the University of Texas-El Paso (UTEP). This NSS facility will assist any academic seismic projects that
would like to use active sources by permitting, engineering, and firing (particularly large) explosive
seismic sources. Complementary to the NSS, this initiative will establish expertise within PASSCAL to
provide field support, education, and outreach to the broader seismology community seeking to use
seismic sources by supporting a ½ time FTE active source position. This individual will act as liaison
between Principal Investigator (PI) and NSS facility, provide PI information (beyond NSS) regarding the
use of explosives, vibroseis, and accelerated weight drop seismic sources (e.g. other source facilities or
rental sources), and provide limited field support for the use of seismic sources that may include the
New Mexico Tech minivib trailer or PASSCAL accelerated weight drops (already owned and maintained
by PASSCAL).
Project Purpose and Business Benefit
Many of the new Grand Challenge initiatives championed by IRIS can be most clearly addressed using
active source seismic methods. Active seismic sources typically reach higher frequencies than
earthquake sources and provide flexibility in source location. Such sources can be used either
independently of earthquake sources or in complementary programs to better image the desired
target(s). An active-source component could enhance the accuracy of many IRIS experiments to provide
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accurate timing, supplement azimuthal coverage, and increase the resolution of shallow structures.
PASSCAL entered the active source arena in 2011 with the purchase of an accelerated seismic source
that has been utilized (to date) throughout the world in hydrogeophysics, cryosphere, tectonics and
education studies. Active source experiments to address structural geology, geochemistry, and other
objectives usually require larger seismic sources, yet no NSF-funded facility or resource is presently
available to the academic community for land-based active source experiments. This lack of support
greatly limits the community that can utilize the active-source method for research studies. The purpose
of this initiative is to provide PI support for basin-scale and crustal-scale active source seismic
experiments in a cost-competitive manner. The NSS facility will be a comprehensive active-source
facility that will provide expertise for enabling effective use of vibrators, weight drops, and explosive
sources for active-source work. The NSS facility also will provide liability insurance, permitting support,
and safely conduct field experiments using the expertise at UTEP that is arguably the last US academic
institution that consistently conducts active source explosive experiments. As a result of this initiative,
the expertise in this methodology will be expanded into the academic community (via training of
scientists interested in gaining these abilities) and will move into the core PASSCAL program.
The NSS initiative received excellent reviews following the scrutiny of the National Science Foundation
(NSF). However, NSF was concerned about supporting an independent seismic facility outside of the
well-established IRIS program. By integrating a streamlined initiative into PASSCAL (a single institution
subcontract), this low cost service will reduce impediments for many seismology experiments both
within and outside the US at scales suitable for studies of hydrogeology, active faulting, volcanic
plumbing, crustal deformation, lithospheric composition, and thermal structure. This initiative will also
train the next generation of explosives shooters and seismologists and provide a broad base of support
to the seismology community.
Project Scale and Duration
This year-to-year subcontract with UTEP and ½ time FTE at the PASSCAL facility will enhance and expand
the variety of experiments that include active sources. As a result, this initiative will provide critical
scientific insights to advance our understanding of Earth processes. The PASSCAL ½ FTE will add
capabilities beyond the UTEP subcontract and explore alternative options (facilities) for explosives,
vibroseis sources (e.g., NEES, UNLV, and industry) and accelerated weight drop sources.
Estimated Project Cost
The estimated cost includes subcontract with University Texas, El Paso ($160,000) and ½ time FTE at the
PASSCAL Instrument facility ($70,000). Total estimated cost is $230,000 per year.
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Estimated Cost Breakdown on Seismic Source Facility at UTEP per Year
Salaries and fringe (3 mo for Harder)
Liability insurance ($5 million policy)
Consultant for safety training
Domestic travel
Subtotal
Indirect costs (49.5%)
Total
PIF-PA-2012-05 V1.0
$54,000
$40,000
$3,000
$10,000
$107,000
$52,956
$159,956
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