Transcript SZO_Summary_Presentation_v3

Summary of Science Concepts
Provided by Workshop Applicants
Diana Roman & Phil Skemer
Major Themes
Major Themes
180
160
Number of Responses
140
120
100
80
60
40
20
0
Observation
Interdisciplinary /
Multidisciplinary
Comparative
E&O
Numerical
Hazards
Experimental
Major Themes
time dependent variation
along-strike variation
pre-, co-, & post-seismic deformation
hazards
shallow mantle /
crustal processes
volcanism
surface geology
3D structure
earthquakes
deep mantle processes
Major Themes
1. What is the structure of subduction zones?
a. 3D imaging of slab, plate boundary interface, deforming mantle, fluid and magmatic
systems
b. surface geology and petrology from both active and ancient SZs
2. What are the relationships among time-dependent processes?
a.
b.
c.
d.
seismicity, including both large and small events
ETS
surface deformation (pre-, co-, and post-earthquake)
eruptions and chemistry of volcanic material
3. How do observations and theory help assess hazards?
a.
b.
c.
d.
earthquakes
tsunami
volcano
landslide
4. How can new observations leverage or be leveraged to yield new and exciting
science?
a. comparative study of subduction zones
i. along strike variation
ii. variation through geologic time
b. theory and numerical approaches
c. experimental methods: deformation, petrology, and geochemistry
Highlights from Workshop Applications
1) Subduction zone structure and dynamics
2) Megathrust earthquakes
3) Volcanic processes
4) Experimental work
5) Biology meets subduction
6) Geomorphology and surface processes
7) Organization and logistics
Highlights from Workshop Applications
Subduction Zone Structure and Dynamics
“Back-arc systems allow us to examine the relative roles of pressure release melting,
as at mid-ocean ridges, and hydrous flux melting, as beneath the volcanic arc. An
exciting approach would be to study a subduction system from trench to back-arc.”
(Robert Dunn, Univ Hawai'i)
Highlights from Workshop Applications
Subduction Zone Structure and Dynamics
“[There are] potential feedbacks among the seismic behavior of the plate interface,
the uplift and consequent (climatically modulated) erosion, and the export of this
detritus back to the trench system. An SZO presents a unique opportunity to
assess how variations in climate and erosion rate influence both the mechanical
behavior of the plate interface and the flux of mass, volatiles, etc. to the magmatic
arc.” (Eric Kirby, Oregon State)
Figure: Wikipedia
Highlights from Workshop Applications
Megathrust Earthquakes
“What in situ conditions and fault properties allow the so-called "spectrum" of fault
slip behaviors to arise? How do the intertwined processes of metamorphism, fluid
release, and fluid flow impact the mechanical state and slip behavior of the
megathrust? SZO's can tackle these questions through offshore geodesy and
borehole observatories that monitor strain... integrated with sampling and lab
programs that provide relevant materials to investigate fault rock rheology, and
heat & fluid flow data to improve models.” (Demian Saffer, Penn State)
From Peng and Gomberg (2010)
Highlights from Workshop Applications
Megathrust Earthquakes
“Seafloor geodetic instruments would be of great use to quantify deformation
during different phases of the seismic cycle and to reveal evidence of interseismic
locking or creeping.” (Marc-Andre Guetscher, Univ. Brest)
Figure from Tadashi Ishikawa via UNAVCO
Highlights from Workshop Applications
Volcanic Processes
“The development of analytical techniques with improved spatial resolution and
lower detection limits is allowing us to study magmatic processes that occur on
timescales of seconds to hours [leading to] synthesis of short-timescale, petrologic
markers of magma ascent with geophysical datasets” (Megan Newcombe, LDEO)
Figure from Cashman and Sparks, 2013
after Humphreys et al. (2006)
Highlights from Workshop Applications
Volcanic Processes
“New observations about magma transfer from the mantle to the surface could be
uncovered under volcanoes arc wide. To drive the development of better
conceptual models of magmatic transport structures a multi-disciplinary array of
instrumentation at least an order-of-magnitude denser than the transportable array
would be needed onshore with a significant offshore component as well.” (Wes
Thelen, USGS)
Figure from iMUSH.org
Highlights from Workshop Applications
Experimental Work
“Scaling of deformation kinetics and reaction kinetics to natural systems could
provide new perspectives on how to interpret frictional stability (as well as the
processes responsible for a wide range of frictional slip behaviors) within the
subducting system.” (Greg Hirth, Brown)
Figure from Brantut et al. (2011)
Highlights from Workshop Applications
Biology meets Subduction
“Understand how carbon is cycled at a convergent margin to generate insights into
the complex interplay between biotic and abiotic carbon cycling in arcs.” (Peter
Barry, Oxford)
Figure from Manning (2014)
Highlights from Workshop Applications
Surface Processes
“Integrating remote sensing, geophysical, and geodetic data of short timescales
(sec. to decades) with geomorphic and geochronology data (centuries to millennia
to mountain building timescales) could provide great insight into the interaction of
geodynamic and surface processes in these regions in a transformative way.”
(Brian Yanites, University of Idaho)
Figure from http://sydney.edu.au/science/geosciences/research/re_earthbyte.shtml