"Subduction Zone Dynamics"
June 19 to July 21, 2017
University of California, Berkeley
The CIDER 2017 summer program focused on subduction zone structure and dynamics. Subduction zones have a dominant control on plate tectonics, are the sites of the world's greatest natural hazards, probably control the formation of the continental crust, and provide pathways for the rehydration and recarbonization of the Earth's mantle, as well as outgassing to the Earth's atmosphere. Significant progress has been made in recent years on unraveling the structure and dynamics of subduction zones, with strong support in the US from geophysical investigations supported by Earthscope and interdisciplinary research opportunities provided by GeoPRISMS. This workshop can also help set the stage for the future of subduction zone research as the EarthScope USArray and GeoPRISMS are winding down.
CIDER's collaborative and interdisciplinary nature provides an ideal venue to expose students and postdocs to the rich developments in subduction zone research, to help synthesize ongoing work in the global subduction system, and to help develop new research teams and research directions. We plan to take the interdisciplinary approach that is common to both CIDER and GeoPRISMS, to develop the science program and tutorial content. In brief, the purpose of CIDER 2017 is to bring together junior and senior scientists from different disciplines to cross-educate each other and help advance this inherently multi-disciplinary research topic.
We expect to develop a schedule where we investigate the subduction zone systematically from the incoming plate and the shallow forearc to the processes in the deep slab interior and those of the mantle wedge and overriding plate.
Overarching questions are diverse and include:
- “What is the hydration state of the incoming plate?”
- “How does subduction initiate?”
- “What is the role of the accretionary prism and what controls whether margins are erosional or accretional?”
- “What controls the distribution of seismic and aseismic slip along the shallow thrust zone?”
- “Why do some subduction zones show no large thrust earthquakes?”
- “What controls the spectrum of fault creep and rupture including episodic tremor and slip?”
- “How do metamorphic reactions control the release of fluids and seismicity?”
- “How do fluids leave the slab and trigger wedge melting?”
- “How do continental arcs evolve and contribute to the formation of the continental crust?”
- “What leads to the spectrum of arc volcanic unrest and activity?”
- “What are the relative rates of the main processes occurring at subduction zones?”
- "Why do some subducted slabs stagnate at 660 km or 1000 km depth?"
We plan to tap into the research expertise involved with the geophysical and geochemical work sponsored by Earthscope and GeoPRISMS/MARGINS and use in particular (although not exclusively) the Cascadia, Alaska-Aleutian, Japan, Central America and Izu-Bonin-Mariana (IBM) subduction zones as case studies. Cascadia offers a unique perspective as it is one of the warmest subduction zones on the planet. The Alaska-Aleutian arc offers strong transitions in driving functions including changes in age, speed and convergence direction along the arc, and depth to the slab surface. IBM offers a classic island-arc setting with an active backarc spreading center and an apparent absence of large thrust earthquakes. Japan is by far the best instrumented subduction zone on the planet and offers contrasts between very young and warm subduction in the South and mature subduction to the North. Central America in terms of thermal properties intermediate and has been exposed well by long-term collaborative research between Central American, US and German scientists.
- Christy Till Arizona State University
- Peter van Keken Department of Terrestrial Magnetism, Carnegie Institution for Science
- Jessica Warren Univ. of Delaware</li>
- Doug Wiens Washington University, St Louis (Lead organizer)
- Barbara Romanowicz U.C. Berkeley and College de France, Paris (ex-officio, CIDER PI)
Similarly to previous CIDER summer programs, the program was structured as follows:
Week 1 (June 19 -23)</i>: Informal , unstructured program for participants at the assistant professor level or higher.
The unstructured part of the program is meant to facilitate interaction between members of the community that have burgeoning plans to develop collaborative projects. Come to CIDER to plan your collaborative proposals!! You will have office space, access to a desktop computer and printers, a quiet environment away from your home institution, and the possibility to interact with colleagues from various disciplines in an informal way.
Weeks 2-5 (June 25 - July 21)</i>: Lectures, tutorials and workshop open to advanced graduate students and post-docs, as well as senior participants.
Graduate students and post-docs signing up for the tutorial part (weeks 2 -5) are required to stay for the 4 weeks of the tutorial program. Exceptions may be considered but priority will be given to those that commit to stay for 4 weeks. During the 2nd week of lectures (week 3 of the summer program), research questions that require a multi-disciplinary approach will be formulated, and the participants will be divided up into several groups (typically 3-5), composed of a mix of junior and senior participants, and a balance of disciplines.
During the following two weeks these research groups will work on defining and addressing a well focused research project. Our experience is that one week of "workshop" is not enough to get anything done, so staying for the 4th week, i.e. 2nd week of workshop, is essential. Each group will present their work/findings on the last day of the program (see presentations from previous CIDER programs). Participants will also have free time to catch up with their regular research and other duties.
Participants may bring spouses and we will do our best to accommodate families, and in particular give references for childcare. There are many programs for children on and off campus.
A "kick-off" workshop was held at Berkeley on Sunday December 11, 2016. The program of that workshop is available on the pre-AGU 2016workshop website.
Travel and on-site expenses is provided to those senior participants that stay for two weeks or longer and to grad students/post-docs that commit for the 4 weeks of the lecture tutorial program. We cannot provide support for travel from outside ofthe US. However, on-site support for foreign participants (senior or junior) accepted to the program is provided.
Support for CIDER 2017 participants is provided by the NSF/FESD program through the CIDER Synthesis Center grant to U.C. Berkeley (PI B. Romanowicz).
This summer program was held at the University of California, Berkeley, CA, USA.