SCD Implementation Workshop

   January 5-7, 2011
Bastrop, Texas

– Workshop Complete –

AnnouncementVenueAgenda - Presentation archiveBreak out presentationsWhite Papersmore infoOutcomes

The SCD Implementation Workshop is now Complete!


A MARGINS/GeoPRISMS-sponsored workshop on the new GeoPRISMS Subduction Cycles and Deformation (SCD) Initiative will be held January 5-7, 2011 in Austin, Texas. This workshop will produce the implementation plan for the SCD component of the GeoPRISMS Science Plan. Participants will further refine the themes and the unanswered questions proposed for the SCD Initiative in the GeoPRISMS Draft Science Plan. The SCD Initiative addresses these key topics:

  1. Controls on the size, frequency and slip behavior of subduction plate boundaries
  2. Spatial and temporal patterns of deformation through the seismic cycle
  3. Linkages between volatile release and the rheology of the plate boundary interface
  4. Storage, transfer, and release of volatiles through subduction systems
  5. Geochemical products of subduction and creation of continental crust
  6. Subduction zone initiation and arc system formation
  7. Feedbacks between surface processes and subduction zone dynamics

The workshop will narrow the focus of these seven themes, prioritize scientific objectives, and develop a 10-year implementation plan, including identification of potential collaborations with national and international research partners. An additional goal of this workshop is the selection of one or two “Primary Sites” for focused investigations and to define the desired balance between “Primary Sites” research versus other efforts.

Interested researchers should submit an application online by October 8, 2010. The application should include a brief statement of how the applicant expects to contribute to the workshop’s goals and a short C.V. All scientists interested in subduction-related studies are encouraged to apply, independent of past involvement in MARGINS or GeoPRISMS. Post-docs, senior graduate students, and members of underrepresented groups are especially encouraged to participate. Selected participants will be notified by November 12, 2010. Funding from NSF is expected to cover a significant fraction of travel and accommodation costs for U.S. participants. Questions or comments may be directed to the GeoPRISMS/MARGINS Office at info (at)

Workshop Conveners:

Michael Underwood – University of Missouri-Columbia (co-Chair)
Clifford Thurber – University of Wisconsin-Madison (co-Chair)
Harm Van Avendonk – University of Texas, Austin
Susan Bilek – New Mexico Tech
Heather DeShon – University of Memphis
Michael Gurnis – Caltech
Demian Saffer – Penn State University

Conference venue: Lost Pines Resort

Day 1 | Wednesday, January 5

Phase 1. Sharpen the focus of the seven key topics

8:00 Introduction by conveners | Cliff Thurber, Mike Underwood

8:15 Briefings by GSOC Chair, NSF | Juli Morgan, Bil Haq

9:00 Plenary talks on the seven key topics (Moderators: Underwood and DeShon)
9:00 Key topic 1: Controls on the size, frequency and slip behavior of subduction plate boundaries |  9Mb – Thorne Lay

9:20 Key topic 2: Spatial and temporal patterns of deformation through the seismic cycle |  6Mb – Jeff Freymueller

9:40 Key topic 3: Linkages between volatile release and the rheology of the plate boundary interface |  icon-file 8Mb Greg Hirth

10:00 Coffee break

10:20 Key topic 4: Storage, transfer, and release of volatiles through subduction systems |  4Mb – Paul Wallace

10:40 Key topic 5: Geochemical products of subduction and creation of continental crust  |  6Mb – Maureen Feineman

11:00 Key topic 6: Subduction zone initiation and arc system formation |  9Mb Bob Stern

11:20 Key topic 7: Feedbacks between surface processes and subduction zone dynamics |  7Mb John Jaeger

11:40 Questions and answers; break-out instructions

12:00 Lunch

1:00 Break-out sessions

each on one of the 7 key topics – focus and refine the science; allow for session switching mid-way through

Break-out session leaders:
  1. Emily Brodsky and Chuck Ammon
  2. Kelin Wang and Heather Savage
  3. Ikuko Wada and Shun-ichiro Karato
  4. Doug Wiens and Kathy Cashman
  5. Rebecca Lange and Liz Cottrell
  6. Mark Reagan and Magali Billen
  7. Liz Hajek and Ken Ridgway

3:00 Coffee break

3:30 Talks by early-career speakers (3 talks, 20 min each; moderators Kelley and van Avendonk)

Double-difference tomography applied to the Middle America and Sunda seismogenic zones |  14Mb – Heather DeShon
Persistent rupture segmentation along the Sunda megathrust off Sumatra |  10Mb – Aron Meltzner
Implications of deep transport of slab-adjacent hydrated material at subduction zones |  7Mb – Laura Hebert

4:30 Grad student and post-doc “pop-ups” & “poster advertisements”

5:15 Plenary session: reports on break-outs with open mic – prioritize key topics

6:45 dinner

7:45 Poster session (with cash bar)

Day 2 | Thursday, January 6

Phase 2. Initial consideration of prospective primary sites and implementation issues

8:00 Plenary talks by potential program partners (moderators Gurnis and DeShon)
8:00 Cascadia |  8MbJeff McGuire
8:15 EarthScope |  6MbAnne Trehu

8:30 IODP |  5MbMarta Torres

8:45 International Panel – potential collaborations and infrastructure
JAMSTEC |  8MbShuichi Kodaira
IFM-GEOMAR, National Oceanography Centre, Southampton, University of Florence |  37Mb Heidrun Kopp, Lisa McNeill, Paola Vannucchi
GNS Science |  3Mb Laura Wallace

9:45 Conveners – break-out instructions (Underwood, Thurber)

10:00 Coffee break

10:15 Break-out session

for the key topic, discuss the need for primary sites versus more “cross-cutting” science, identify and prioritize potential primary sites, and define the desired balance between primary sites research versus other efforts; allow for session switching mid-way through.

12:15 Lunch

1:15 Talks by early-career speakers (3 talks, 20 min each; moderators Kelley and Thurber)
perspective |  2Mb – Jamie Barnes
Thermochemical evolution of the mantle wedge |  4MbPaul Hall
Melange zones and metasomatism in subduction zone metamorphic rocks |  7MbSarah Penniston-Dorland

2:15 Plenary session: reports on break-outs, with open mike – begin to narrow the options, merge/blend common interests, and prioritize the primary sites across key topics, implementation realities

3:15 Coffee Break

Phase 3. Pragmatic assessment of prospective primary sites

4:00 Conveners – breakout instructions (Underwood, Thurber)

4:15 Break-out sessions: to discuss details of the science plan, including site selection, specific categories of data acquisition, and partnerships – organize by sites plus thematic

5:15 Grad student and post-doc implementation plan presentation

5:45 Plenary session: reports on break-outs with open mike, narrow the options even more to a small number of viable/pragmatic candidate sites (moderators van Avendonk and Gurnis)

6:45 Dinner

7:45 Poster session (with cash bar)

Day 3 | Friday, January 7

Phase 4. Implementation

8:00 Introduction by conveners – review of goals and deliverables (Underwood, Thurber)

8:15 Plenary session: discussion on sites and vote (if necessary) on site selection; break-out instructions (moderators Underwood and Thurber)

9:30 Break-out sessions: to refine/finalize immature sections of the draft science plan – organize by sites plus thematic (coffee available)

11:00 Plenary session: wrap-up, including consensus on 10-year timeline for implementation (moderators Underwood and Thurber)

Wednesday 1/5 PM — Reports on the main questions of the Draft Science Plan for SCD
Thursday 1/6 PM (1) — Key topic, primary site, and thematic study discussion

Illuminating the Architecture of Crustal Magmatic Systems in the Cascade Region |  300Kb – Olivier Bachmann et al.

Deformation Measurements across an entire Subduction Plate Boundary: Cascadia Subduction Zone |  300Kb – C. David. Chadwell et al.

Four-D Investigation of Subduction Initiation (SI) Magmatism as Revealed in Tethyan Forearc Ophiolites |  300Kb – Yildirim Dilek et al.

Tracking Volatiles at Mount St. Helens from Magma Chamber Residence to Eruption at the Vent |  3Mb – Kimberly Genareau et al.

Computational Geodynamics as a Core Component of a Broad-Based Subduction Initiation Research Program |  3MbMichael Gurnis et al.

The New Zealand Region: A key natural laboratory for studying subduction initiation |  4MbMichael Gurnis et al.

The Aleutian Island Arc near Adak as a GeoPRISMS Focus Site: Finally, a Subduction Factory that actually makes continental crust? |  800KbW. Steven Holbrook et al.

The Leading Edge of the Mantle Wedge: Structural and metamorphic studies of peridotite thrust over metasediments & basalts |  100Kb Peter Kelemen et al.

Comparing Coeval Plutonic and Volcanic Rocks in the Aleutian Arc: Are primitive, mafic lavas representative of arc fluxes? |  200Kb – Peter Kelemen et al.

Exhumed Subduction Margins: An important record of deformation and metamorphic processes |  100Kb – Mary Leech

Seismic Hazards, Continental Deformation, and Mantle Recycling Associated with the Himalayan Continental Subduction Zone |  200KbJames Ni et al.

Metamorphic Processes Implementation Strategy – GeoPRISMS SCD |  3Mb – Sarah Penniston-Dorland et al.

Subduction Initiation and the Need to Study Forearc Crust |  600KbMark K. Reagan et al.

Africa-Arabia-Eurasia Plate Interactions and Implications for the Dynamics of Mediterranean Subduction and Red Sea Rifting |  600Kb – Robert Reilinger et al.

The SW North American Cordillera: an exposed, accessible and underutilized archive of Paleozoic to Cenozoic subduction-initiation processes |  10Mb J. Saleeby et al.

An Implementation Strategy for Understanding Subduction Initiation (SI); Integrated Studies of Naked Forearcs, Ophiolites, and Geodynamic Modeling |  500Kb – Robert J. Stern et al.

The Southeast Mariana Forearc Rift: A Modern Analogue for Forearc Extension during Subduction Initiation |  400KbRobert J. Stern et al.

The Hikurangi Margin, New Zealand: an important natural laboratory to understand subduction thrust behavior |  700Kb  Laura Wallace et al.

The Gulf of Alaska Margin: Potential Focus Site for GeoPRISMS SCD |  200KbLindsay L. Worthington et al.

Helpful Links

Apply to Attend the Workshop
Accept an Invitation to Attend
Submit a White Paper
Final participant list (last update 01-03)
Participant lodging list

Outcomes of the Implementation Workshop for SCD

We are pleased to report on the outcome of the most recent GeoPRISMS planning meeting, the Subduction Cycles and Deformation (SCD) Implementation Workshop, held in Bastrop, TX this past week. Approximately 135 people were in attendance, over a 2.5-day period. Substantial discussion took place both in break-outs and in plenary session, leading to a decisive vote selecting three primary sites for future GeoPRISMS SCD investigations, listed in order of preference: Alaska (including the mainland and Aleutian extension), Cascadia, and New Zealand. Several thematic study topics were also outlined, and will be made available on the GeoPRISMS website in the near future.

Alaska was selected as the highest priority site, as it offers real opportunities to address a wide variety of questions outlined within the SCD science plan. However, it was recognized that GeoPRISMS investigations there will require significant ramp-up time, and strong integration with EarthScope activities that are still in the planning stages.

Cascadia offers outstanding immediate-term opportunities, with the ongoing deployment of the amphibious array as part of the Cascadia Initiative, and the coalescence of a range of US, Canadian, and international scientists for coordinated onshore and offshore investigations.

New Zealand elicited significant excitement, in part due to major national investments both on- and off-shore by their national government, and growing international collaborations in that setting. New Zealand also exhibits a wide range of fault slip and volcanic processes with significant along-strike variations in a compact setting, as well as excellent exhumed exposures of arc crust, all integral to the major SCD questions. In addition, GeoPRISMS investigators in New Zealand can leverage previous MARGINS research from the Source-to-Sink efforts along the northern Hikurangi margin. An IODP proposal is also in the pipeline.

The logistics and timeframes for studying each of the three primary sites will be different, and such details will be outlined within the Implementation Plan arising from the meeting.

We would like to thank the meeting attendees for their participation in the process of reaching consensus on the future direction of the SCD initiative. Also, a special thanks to all of the speakers, break-out group leaders, and White Paper authors for their contributions in making the workshop such a success. Finally, we want to recognize the enthusiastic participation of the graduate students and post-docs for their input.

A number of important tasks lie ahead. The conveners and break-out leaders will develop a draft of the implementation plan by January 29 for review by the community. This plan will be submitted to NSF by early February. The primary sites will require additional planning workshops to further focus community efforts and develop proposals for gathering of community data sets, etc.

Workshop Conveners (in alphabetical order):

Susan Bilek – New Mexico Tech
Heather DeShon – Memphis University
Mike Gurnis – California Institute of Technology
Katie Kelley – University of Rhode Island
Demian Saffer – Pennsylvania State University
Cliff Thurber – University of Wisconsin (SCD Implementation Co-Chair )
Mike Underwood – University of Missouri (SCD Implementation Co-Chair )
Harm van Avendonk – University of Texas, Austin
Julia Morgan – Rice University (Chair, GeoPRISMS Steering and Oversight Committee)