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experimental community requires coordinated and structured
growth in the numbers of researchers involved in physical experi-
ments as well as instructors engaging students with classroom
experiments.
PHYSICAL EXPERIMENTS PROVIDE CRITICAL INSIGHTS
A strong U.S. physical modeling community will have mani-
fold benefits for research and teaching in tectonics. Below are a
few examples of the insights provided by experimental data that
cannot be gained by other approaches.
Provide Data for Calibration of Numerical Models
Numerical simulations of crustal deformation are plagued with
uncertainties about crustal structure, strength, and evolution.
Within physical experiments, the boundary conditions are
known, the material rheology is constrained, and the evolution of
deformation can be directly observed. Experimental results are
the perfect data sets for validating our numerical models before
we apply them to crustal systems.
Provide Insight into Specific Processes
Within the laboratory, we can isolate single mechanisms
contributing to tectonic deformation. Scaled physical experiments
with controlled boundary conditions and constrained material
rheology allow us to pinpoint the impact of targeted processes.
Insights from this approach can assist the interpretation of field
data where multiple processes and mechanisms may have acted to
produce complex deformation patterns.
Outreach and Teaching
Understanding geologic time is one of the hardest concepts for
students new to geology. Physical experiments can assist these
students because they demonstrate slow geologic processes
happening over millions of years within minutes on the tabletop.
This helps students to integrate both space and time as they
directly observe the three-dimensional deformation and temporal
evolution of structures. The hands-on approach complements
other styles of teaching within the classroom and reaches student
with diverse learning strengths. Additionally, physical experi-
ments provide an accessible means for hypothesis testing in the
classroom because the boundary conditions and material proper-
ties can be manipulated (Feldman et al., 2010). Furthermore, the
visual and hands-on nature of physical experiments engages and
inspires students and the public alike.
Physical experiments provide the only mechanism for direct
observation of the processes of tectonic deformation. Consequently,
they hold the key to understanding information obtained in the
field that documents the results of deformation and analytical/
numerical models that capture the physics of deformation. To best
understand tectonic deformation, we need to use a variety of
approaches, including physical experimentation.
FUTURE DIRECTIONS
In an effort to strengthen and expand the U.S. community of
physical experimentalists in tectonics, the U.S. National Science
Foundation sponsored a workshop in 2015 on “Analog Modeling
of Tectonic Processes” at the University of Massachusetts–Amherst
with 46 participants. This workshop was a great success and
helped connect researchers and teachers using physical modeling.
One of the outcomes of the workshop was learning that it is essen- GSA TODAY | www.geosociety.org/gsatoday
tial to continue growing the U.S. community of experimentalists,
to increase networking among the researchers so that we can 37
advance our techniques, enable sharing of techniques and
teaching approaches involving physical models, and to facilitate
collaboration between experimentalists and others investigating
tectonic processes. A valuable aspect of the 2015 workshop was the
presentation of innovative curricula, which inspired participants
to implement new activities within their courses. Having experi-
ment-focused workshops on a regular basis as well as continued
support for research and teaching involving physical modeling
will grow this community and strengthen our understanding of
deformational processes. A successor workshop planned for 2017
will continue this effort.
Within the next ten years we hope to continue strengthening
the collaboration between field geologists, numerical modelers,
and experimentalists to build a stronger three-legged stool upon
which we can advance our tectonic understanding.
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Manuscript received 27 May 2016
Revised manuscript received 26 Aug. 2016
Manuscript accepted 10 Sept. 2016