Please see below for sessions of interest to the GeoPRISMS Community, taking place at the 2016 AGU Fall Meeting, December 11-15 in New Orleans, LA. AGU abstract submission deadline is Wednesday August 2 at 23:59 EDT.
Submit your abstract: https://fallmeeting.agu.org/
Your session is not listed? Email us at firstname.lastname@example.org and we’ll be happy to include your session to the list.
T005: Breaking Up is Never Easy: Why Do Some Rifts Fail and Others Succeed?
Session ID: 22413
The breakup of continents is a fundamental process of plate tectonics. However, we have not yet identified the crucial ingredients that permit complete rupture of strong continental lithosphere. Studies of continental breakup are biased towards success¬ stories – rifts that evolve to oceanic spreading. Some extension episodes cease before this point, presumably in the absence of some fundamental process, initial condition(s), or forcing. Investigations of “failed rifts” may help isolate key processes or conditions that enable continental breakup, particularly when compared to successful examples. Outstanding questions include: Does rift success/failure depend on intrinsic or far-field properties? How do pre-existing structure, magma, and volatiles influence rift initiation, continuation, and extinction? Are failed rifts actually “paused rifts” that can later be reactivated? Do analogous mechanical controls apply to extinct seafloor spreading centers? We solicit contributions from diverse geoscience perspectives, including geodesy, geodynamics, geochemistry/petrology, volcanology, structural geology and seismology.
We look forward to seeing you in New Orleans!
Zach Eilon, Natalie Accardo, James Muirhead, Sarah Stamps
T007: Continental Rifts and Passive Margins: Geology, Geophysics, Geodynamics
Session ID#: 22111
This session invites contributions on rifts and rifted margins that integrate new data sets, approaches or viewpoints. Studies can range from the outcrop to the basin or lithospheric plate scale, and include global examples. Innovative concepts and techniques based on field geology, seismology, geodesy, marine geophysics, plate reconstructions, geochemistry, sedimentology, or modeling are encouraged. Topics may include but are not limited to fault dynamics, shear zones, tectono-magmatic and sedimentary processes, impact of volatiles, the continent-ocean transition, influence of mantle dynamics and surface processes, and the role of tectonic inheritance. We particularly encourage submissions that explore along-strike structural and magmatic variations in rifts and passive margins linked to 3D modeling studies. Emphasis will be given to presentations conveying an integrated picture by bridging spatial or temporal scales, or by combining results from active rifts, failed rift arms, passive margins or fossil rifted margins exposed in mountain belts.
Conveners: Sascha Brune (Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences), W Roger Buck (Columbia University of New York, LDEO), Patricia Persaud (Louisiana State University), and Gianreto Manatschal (University of Strasbourg)
T011: Eastern North American Margin: Multidisciplinary Studies
Session ID#: 24298
The Eastern North American Margin (ENAM) records a complex geologic and tectonic history, encompassing two complete Wilson cycles from supercontinent assembly to breakup over the past ~1.3 billion years. It is a natural laboratory to examine the orogenic histories, the lithospheric behavior, and the interaction between crust and upper mantle beneath passive margins, which are fundamental for our understanding of plate tectonics in general. This session invites multidisciplinary contributions from geology, geophysics, tectonics, and geodynamics on the ENAM with new datasets, new methods, new models, and new ideas, with particular interests of the integrated results from multiple disciplines on the study of the 3-D geometry and the tectonic evolutions of this passive margin. Topics may include but are not limited to understanding of the tectonic history of orogenic processes, the crustal and upper mantle structures and dynamics, the nature and origin of magmatic activities and the links to tectonic processes.
Xiaotao Yang (University of Massachusetts Amherst), Cong Li (University of Massachusetts Amherst), Michael L Williams (University of Massachusetts Amherst), Vadim L Levin (Rutgers University)
T015: Fluid migration through subduction zones: observations and the consequences on geodynamic processes and natural hazards
Session ID#: 25865
Water plays a vital role in the Earth’s evolution. At subduction plate boundaries, vast quantities of fluid are exchanged between the Earth, ocean and atmosphere; however, water transport through subduction zones is only partially understood. Volatile cycling is fundamental to the petrogenesis and eruption of arc magmas. Fluids and dehydration reactions may also play a key role in the earthquake cycle. This session will address some key scientific questions of volatile cycling. What is the role of the slab mantle as a vessel for transporting water into the subduction zone? What are the pathways of volatiles through the subduction system thereby impacting geodynamic processes (e.g. mantle flow)? How are volatile pathways manifested in seismic, volcanic and mineralization potential? We welcome contributions from a range of studies on diverse subduction environments from various disciplines (e.g., but not limited to: geophysical imaging, rock physics, geochemistry, geodynamic modelling).
Conveners: Stephen Paul Hicks (University of Southampton), Lidong Bie (University of Liverpool, Liverpool), Andreas Rietbrock (University of Liverpool)
T016: Geochemical Evolution of Convergent Margins from Asthenosphere to Atmosphere
Session ID#: 21897
Do you have an interest in the climate-tectonic-magmatic-
We invite you to submit an abstract to the topical session “Geochemical Evolution of Convergent Margins from Asthenosphere to Atmosphere” at this year’s AGU Fall Meeting in New Orleans, LA (Dec. 11-15, 2017). We aim to bring together a diverse group of geochemists tackling interdisciplinary questions at modern and ancient convergent margins.
Invited Speakers: Cin-Ty Lee (Rice University) and Carina Hoorn (University of Amsterdam).
The session description is below. We hope to see you in New Orleans!
Kendra Murray, Mauricio Ibañez-Mejia, & Alexander Rohrmann
The importance of links between processes in the mantle, crust, hydrosphere, and atmosphere at convergent margins is increasingly clear, but the mechanisms, timescales, and even directionality of these connections remain poorly understood. These interactions influence the growth, recycling, and destruction of the lithosphere; induce rapid shifts in surface elevation and produce high topography that can affect atmospheric circulation; and drive feedbacks between precipitation, rock deformation, uplift, basin development, landscape evolution, and biologic change. Furthermore, convergent margins generate the planet’s largest earthquakes and modulate greenhouse-gas budgets via volcanism and chemical weathering. In this session, we aim to bridge temporal, spatial, and disciplinary gaps between geochemical studies of Andean-type margins. We invite contributions that place the geochemistry of modern and ancient convergent margins within the context of these interactions. We particularly welcome multi-method approaches that include geochronology, thermochronology, cosmogenic nuclide-dating, stable isotope measurements, leaf-wax lipid-biomarkers, or other biological proxies.
T028: New Insights On The Cascadia Subduction Zone From Offshore And Amphibious Studies
Session ID#: 24812
Subduction zones, one of Earth’s fundamental tectonic environments, play a key role in many Earth processes. Consequently, they require study by interdisciplinary methods. However, our understanding of subduction zones has been limited by a lack of offshore and amphibious data. At the Cascadia subduction zone, new data collected over the last several years have helped close this gap, elucidating a wide range of new insights, including the structure of the incoming lithosphere, the role of water and volatiles in the subducting plate, asthenospheric flow above and below the subducting lithosphere, the transition from locking to slipping behavior along the plate interface, and the nature of episodic tremor and slip. We invite contributions broadly related to Cascadia geoscience that focus on new results from seismology, magnetotellurics, geodesy, geodynamics, hazards, paleoseismology, geochemisty and petrology, with particular emphasis on insights gained from the contribution of offshore and amphibious data.
Conveners: Helen A Janiszewski (Columbia University of New York), William Bythewood Hawley (University of California Berkeley), Kerry Key (Institute of Geophysics and Planetary Physics La Jolla), and Matthew James Cook, Scripps Institution of Oceanography)
T032. Role of Pre-Existing Structures on Plate Deformation in Continental Rifting and Subduction Zones
Session ID: 27474
This session seeks to discuss the current state of knowledge of plate deformation in continental rifting and subduction zones as affected by the presence of pre-existing structures. Studies have shown how strain is accommodated along pre-existing structures, and how geological hazards are localized where the older structures are present. Other studies have shown how pre-existing structures are not important in the formation of new faults. Understanding the effects of these older structures are important to comprehend seismic hazards, plate kinematics, initiation and evolution of continental rifting, subduction initiation, and strain partitioning in subduction zones. We seek contributions that use geophysical (seismic, geodetic, remote sensing, potential fields), numerical and/or analog modeling, and geological techniques to understand strain accommodation, geologic hazards, subduction processes, deformation history, and plate kinematics, as affected by pre-existing structures. This session also encourages contributions on future research directions on strain accommodation on continental rifting and subduction zones.
Daniel A. Laó-Dávila, Estella A. Atekwana, and Mohamed Abdelsalam
Oklahoma State University
T036: Subduction Dynamics Across the Scales
Session ID#: 25133
Subduction zones display a wide variety of tectonic and earthquake behaviors across a range of timescales. Seismic tomography, laboratory and numerical models have helped to understand plate boundary evolution at the geological time-scale. However many aspects of short-term subduction dynamics remain unclear. The series of thrust megathrust earthquakes of the last 15 years, besides highlighting the social relevance of geodynamic studies, has opened a window into the dynamics of subduction zones at the seismic cycle time-scale. The combination of seismic, geodetic and numerical modeling has helped to understand the physical characteristics of the megathrust earthquakes and the role of the fault geometry, temperature, fluid circulation, petrology and seismic/aseismic energy partitioning to the dynamics convergent margins. We welcome contributions from geodynamicists, seismologists, geodesists and geologists aiming at exploring the relationship between subduction zone dynamics and seismic cycle.
Conveners: Gabriele Morra (University of Louisiana at Lafayette), Emma Hill (Earth Observatory of Singapore), Thorsten W Becker (University of Texas at Austin, Austin), and Ylona van Dinther (ETH Swiss Federal Institute of Technology Zurich)
S035: Seismically surveying North America: synthesis and emerging ideas as USArray spans Alaska and the CCArray initiative builds momentum
Session ID#: 24626
A systematic broadband seismic survey of an entire continent is a former pipe dream from the seismology community that has recently made major steps toward reality. The EarthScope program’s USArray Transportable Array has successfully covered the contiguous 48 states of the US, and is just reaching its maximum extent in Alaska and northwestern Canada. This session welcomes studies striving to synthesize new insights into continental structure, wave propagation, and seismic sources illuminated by comprehensive coverage of the contiguous US, as well as studies with nascent results and hypotheses from Alaska and northwestern Canada. Coverage of North America remains incomplete and the growing CCArray initiative may offer an opportunity to connect the existing broadband data sets by systematically sampling the Canadian Cordillera. Studies with relevance to the potential science targets, design, and capabilities of the CCArray concept are encouraged.
Conveners: Brandon Schmandt (University of New Mexico), Scott Burdick (University of Maryland College Park), Pascal Audet (University of Ottawa), and Emily Hopper (Brown University)