Congested Subduction Workshop
A two day workshop at the Mt Stromlo Observatory, Australian National University, March 16-17, 2020 exploring the dynamics of congested subduction zones.
Registration is free and so is lunch !
- Louis Moresi (Research School of Earth Sciences, Australian National University, louis.moresi@anu.edu.au)
- Peter Betts (School of Earth Atmosphere and Environment, Monash University, peter.betts@monash.edu.au)
- Joanne Whittaker (Institute for Marine and Antarctic Studies, University of Tasmania, jo.whittaker@utas.edu.au)
- Meghan Miller (Research School of Earth Sciences, Australian National University, meghan.miller@anu.edu.au)
Subduction zones suck the cold oceanic plates down into the mantle, releasing gravitational potential energy and driving the global geological circulation. They naturally attempt to ingest all the anomalously buoyant material embedded in the oceanic plates including seamounts, under-plated plume materials, large igneous provinces, micro-continents and even the continents themselves. This is a fundamental component of the geological canon for which there is very little holistic, predictive dynamic modelling and many outstanding questions. At congested subduction zones there is a competition between positive and negative buoyancy from which complex structure is emergent.
Congested subduction zones necessarily evolve in three dimensions. The response of a subduction zone in response to ingestion of buoyant material is a predictable evolution in the planform of the subduction system, the formation of slab windows, and a time-dependent change in the stress-state of the over-riding plate.
Program
Monday, March 16, 2020 @ 9:30 — Tuesday, March 17, 2020 @ 3:30
CSO Common Room, Research School of Astronomy & Astrophysics, Mount Stromlo Observatory. For information on how to get to the workshop see below.
Note: a number of speakers have asked to present via videoconference because of the ongoing travel restrictions. We are keeping the schedule flexible as a result.
Presentations can be uploaded to a shared dropbox folder at this link.
| Schedule | Session | |
|---|---|---|
| Monday am | ― | Welcome coffee & introduction |
| ― | Congested subduction: theory & observations | |
| ― | Signatures of congestion in the record of arc volcanism | |
| ― | Lunch | |
| Monday pm | ― | Regions: The Banda subduction system |
| ― | Discussion | |
| ― | Drinks / Posters | |
| ― | Dinner (Canberra) | |
| Tuesday am | ― | Regions: The Alaskan subduction system |
| ― | Regions: The New Zealand subduction system | |
| ― | Lunch | |
| Tuesday pm | ― | Regions: The Himalayan collision |
| ― | Discussion |
Notes to all participants — this is a discussion meeting with plenty of opportunity to interact with speakers. Please feel free to bring along a laptop in case you wish to present some material during discussion time. We also welcome posters of general interest in the very broad field of subduction studies
Presenters
| Name / Affiliation | Talk / Poster Title |
|---|---|
| Romain Beucher, ANU | T: UWGeodynamics for subduction modeling |
| Peter Betts, Monash | T: New Zealand, the Gawler, and non-newtonian mantle influence on deep subduction - a smorgasbord of subduction congestion |
| Fangqin Chen, ANU | P: Modelling subducting slabs in a spherical domain |
| Brendan Duffy, Melbourne | T: The Gondwanan rocks of Timor are not Australian (recently anyway) |
| Caroline Eakin, ANU | T: The Mantle Response to Peruvian Flat-Slab Subduction |
| Rebecca Farrington, Melbourne ( * ) | T: TBA |
| Voon Hui La, ANU | T: Evidence for strong lateral seismic velocity variation in the lower crust and upper mantle beneath the California margin |
| Chengxin Jiang, ANU | T: Upper mantle Seismic Structure of Alaska From Rayleigh and S Wave Tomography |
| Ben Mather, Sydney | T: Intraplate volcanism controlled by rates of subduction along the Tonga-Kermadec trench |
| Anders McCarthy, Bristol ( * ) | T: Congested subduction in the Alps and Pyrenees |
| Meghan Miller, ANU | T: On the cusp of a tear-imaging inherited structures beneath the Banda Arc |
| Louis Moresi, ANU | T: Congested subduction, the Big Picture |
| Robert Pickle, ANU | T: The Hikurangi Margin: Zealandia |
| Andres Rodriguez, Melbourne | T: Dynamics of arc-continent collision |
| Sarah Roeske, UC Davis (Remote) | T: Modern and Mesozoic congested subduction as viewed from the crustal tectonic and rock record. |
| Gideon Rosenbaum, U Queensland | T: Slab tearing and the origin of SGAM (Spatially and Geochemically Anomalous arc Magmas) |
| Dan Sandiford, UTas ( * ) | T: Subduction kinematics, flexure and earthquakes |
| Benoit Tauzin, ANU | T: NoLiMit: Software and Physics-Based Catalogs of Seismic Waveforms for Analyses of the Earth’s Mantle Transition Zone |
| Jo Whittaker, UTas ( * ) | T: the formation of LIPs, and talk about the dredging of the Louisiade Plateau and the congestion of the Pocklington Trough |
| Sebastian Wong, GA | P: Provenance and structure of the Yancannia Formation, southern Thomson Orogen: Implications for the tectono-stratigraphic Cambrio-Ordovician western Tasmanides |
| Ping Zhang, ANU ( * ) | P: Understanding arc-continent collision in the Banda Arc through seismic image |
| Siyuan Zhao, ANU | T: TBA |
( * ) - Participating by video-conference
Venue
Commonwealth Solar Observatory Common Room, Research School of Astronomy & Astrophysics, Mount Stromlo Observatory.
The CSO is an award winning reconstruction of the original observatory buildings after the 2003 bushfires.
Acknowledgement
This workshop is supported by the Australian Research Council through the Discovery Grant Program (DP150102887)