THE SZ4D INITIATIVE: AN EMERGING OPPORTUNITY FOR COORDINATED RESEARCH IN SUBDUCTION ZONE DEFORMATION ACROSS TEMPORAL AND SPATIAL SCALES (Invited Presentation)

The SZ4D Initiative, or Subduction Zone Processes through Space and Time, is an emerging community-driven activity that aims to develop an integrated and sustained research effort to address the fundamental processes underlying the hazards presented by subduction. Megathrust events and other earthquakes, tsunamis, volcanic unrest, and processes that shape land- and seascapes associated with plate convergence, all unfold over seconds to millions of years. New technologies, including ocean-bottom and conventional seismic networks, high-rate and real-time geodetic systems as well as the emergence of offshore geodesy, high-resolution imaging of geomorphology, and continuous multi-parameter instrumentation of volcanoes, are all yielding revolutionary advances in understanding of active processes. Simultaneously, novel geochronologic, paleoseismologic, and geologic approaches to faulting processes and time scales up, down, and across the subduction system are integral to advancing new discoveries. Laboratory experiments ranging from fault friction to petrology and geochemical systems will be required to understand the deformation underlying hazard, as will new modeling capabilities that integrate geologic and geophysical observations.

NSF has therefore recently funded a three-year planning effort for SZ4D, known as a Research Coordination Network, to develop broad community consensus on a blueprint for a decadal-scale integrative new research initiative. SZ4D is envisioned to build on the successes of recent programs such as Earthscope and GeoPRISMS but with a specific focus on subduction-related deformation that leads to hazard. The SZ4D Steering Committee is establishing “Working Groups” (WG) that will include a broad cross-section of the scientific community to define high priority objectives and develop tractable and compelling experiments and lines of inquiry to achieve objectives. Two of these WGs are concerned with (1) faulting processes associated with locking, rupture, slow slip and potential precursors, and brittle to ductile plate boundary processes, and (2) the subduction deformation drivers of surface processes and landscape evolution both on land and under the sea. In this presentation, examples of leading-edge research and key questions on these and related topics will be used to highlight SZ4D objectives and encourage community participation.