GeoPRISMS sessions of interest at the 2019 AGU Fall Meeting

Every year the GeoPRISMS Office compiles a list of sessions of interest to the GeoPRISMS Community, taking place at the 2019 AGU Fall Meeting, December 9-13 in San Francisco, CA.
Submit your abstract. Abstract submission deadline is Wednesday July 31.
Your session is not listed? Email us at info <at> to include your session to the list.

  • T001. 4D strain localisation during rifting: from border faults to spreading ridges
  • T026. Integrating Plate Interface Rheology and Seismicity with Subduction Zone Geodynamics
  • T028. Interplay between structure, fluids, and deformation processes at subduction zones
  • T034. Multidisciplinary investigations of the Aleutian-Alaska Subduction Zone
  • T044. Segmentation and Supercycles: Observations and Models of Earthquake Recurrence Patterns
  • T050. Subduction Top to Bottom 2 (ST2B-2): Processes and Products Modern and Ancient
  • T051 – Subduction Zone Observation through Time and Space: Path to an SZ4D Initiative on the Science of Subduction Hazards
  • T059. The tectonic fabric of the seafloor: Propagators, microplates and beyond
  • V008. Boom, Zap, and Roar: Multi-disciplinary characterization of volcanic explosion, jet, and plume dynamics
  • V012. Chemical and mechanical processes at plate margins: insights from the exhumed rock record
  • V015. CONVERSE: Community Network for Volcanic Eruption Response – Coordination to Detect Eruption Precursors, and Respond to Volcanic Unrest and Eruptions
  • V026. Interactions between Magmatism, Tectonics, and Faulting in Rifts, Arcs, Ridges, Calderas, and Volcanic Fields
  • V027. Izu-Bonin-Mariana arc system: synthesis and remaining questions
  • V040. Rates and timescales of magmatic processes recorded in minerals
  • S002 Centennial: One Hundred Years of Seismology
  • S003 Centennial Session: Forensic Seismology, Origins and Future
  • S004. Centennial: The Anisotropic Earth
  • S012. Earthquakes Related Cascading Hazards
  • OS022. Marine Geohazards
  • OS025. Submarine Canyons, Channels, and Processes That Shape the Seafloor
  • G012. Plate Motion, Continental Deformation, and Interseismic Strain Accumulation
  • MR005. Carbon and Hydrogen in the Deep Earth
  • MR028. Rock Damage in Fault Zones


T001. 4D strain localisation during rifting: from border faults to spreading ridges

Conveners: Jack Williams (Cardiff University), Luke Wedmore (University of Bristol), Donna Shillington (Lamont-Doherty Earth Observatory), Ritske Huismans (University of Bergen)

Invited Speakers: Lisa McNeill (University of Southampton), Rebecca Bendick (University of Montana)

Abstract: Continental rifting and breakup is thought to proceed by progressive strain migration and localisation. Observations of how strain migrates during rifting are, however, difficult to obtain; consequently many questions remain about the rates and style of extension over the life of a rift. In this session we welcome contributions that present new observations of strain distribution in rifts, and explore how these results can be used to investigate the mechanisms and conditions that control strain migration and localisation through space and time, account for why some rifts fail and others succeed, and examine seismic hazard in active rifts. We particularly encourage multi-disciplinary studies that include aspects of geodesy, structural geology, geochemistry, seismology, numerical and analogue modelling, and active and passive source geophysics, from active and ancient rifts.


T026. Integrating Plate Interface Rheology and Seismicity with Subduction Zone Geodynamics

Conveners: Adam Beall (Cardiff Univ.), Whitney Behr (ETH), Luca Dal Zilio (Caltech) and Yajing Liu (McGill Univ.)

Invited Presenters: Paola Vannucchi (Royal Holloway, Univ. of London) and Sylvain Barbot (USC)

Abstract: The rheological and frictional properties of the plate interface determine the degree of interseismic locking, seismic rupture size and the geodynamic coupling that influences long-term crustal deformation and possibly plate velocities. In turn, the interface rheology is influenced by petrology, stress state, temperature, fluid pressure and sediment thickness, which are all controlled by the broader geodynamics. A holistic understanding requires integrated studies of spatial scales ranging from fault/shear zones to tectonic plates and temporal scales from seconds to million-years. We welcome contributions from all relevant disciplines that use observations or models to explore the relationships between fault/shear zone rheology, megathrust seismicity and broad-scale geodynamics.

T028. Interplay between structure, fluids, and deformation processes at subduction zones

Conveners: Shuoshuo Han (University of Texas Institute for Geophysics), Tianhaozhe Sun (The Pennsylvania State University), Laura Wallace (GNS Science), Christie Rowe (McGill University)

Abstract: Deformation processes at subduction zones span a vast range of spatial and temporal scales and contribute to the long-term margin evolution and mass transport through the earthquake cycle and beyond. Individual earthquakes and slow slip events involve complex patterns of deformation and fluid effects. Various modes of elastic, viscous, and plastic deformation shape the structure across the plate boundary fault zone, and within both the upper and lower plates during individual events and over longer timescales. Numerous recent onshore and offshore investigations have connected fault slip, fault zone and wall rock properties, and highlight the interplay between structure, fluids, and deformation processes in the subduction system. In this session, we invite contributions studying the key controls of subduction zone deformation, structural evolution, the role of fluids, and the associated geohazards. Multi-disciplinary contributions from geological, geophysical, and laboratory experimental studies, as well as modeling studies that integrate observations, are all welcome.
T034. Multidisciplinary investigations of the Aleutian-Alaska Subduction Zone

Conveners: Xiaotao Yang (Harvard University), Tamara N. Jeppson (Texas A&M University), Julie Elliott (Purdue University), Daniel J. Rasmussen (Lamont -Doherty Earth Observatory, Columbia University)

We would like to draw your attention to our AGU session: “T034. Multidisciplinary investigations of the Aleutian-Alaska Subduction Zone”. Recent initiatives including EarthScope and GeoPRISMS have generated a wealth of new data in the region, providing a unique opportunity for integrated studies of this dynamic subduction system. We aim to highlight and facilitate such studies by bringing together contributions from geology, geophysics, geochemistry, volcanology, rock physics, geochronology, tectonics, and geodynamics. Please consider contributing to our session.

Invited Speakers: Geoffrey Abers (Cornell University), Jessica Larsen (University of Alaska, Fairbanks)

Abstract: The Aleutian-Alaska subduction zone (AASZ) is marked by lateral variations in the subducting and overriding plates, subduction obliquity, magma composition, and eruption frequency. It is home to 54 historically active volcanoes, a volcanic gap associated with flat slab subduction, and abundant subduction-related seismicity.The AASZ is an ideal place to address a variety of subduction-related questions, most effectively through cross-disciplinary collaborations. This AGU session aims to facilitate sharing of new data and results across disciplines to help elucidate AASZ processes including but not limited to characteristics of the slab; seismogenesis and fault slip behavior; upper plate deformation processes; magma generation, fluid/volatile transport, and eruption processes; and linkages between processes. We invite contributions investigating the AASZ involving geology, geophysics, geochemistry, volcanology, rock physics, geochronology, tectonics, and geodynamics, with a particular interest in studies integrating results from multiple disciplines and/or across scales.

T044. Segmentation and Supercycles: Observations and Models of Earthquake Recurrence Patterns

Conveners: Belle Philibosian (US Geological Survey), Aron Meltzner (Earth Observatory of Singapore / Nanyang Technological University)

Invited Speakers: Tom Rockwell (San Diego State University), Daniel Melnick (Universidad Austral de Chile)

Abstract: Earthquake rupture segmentation and cyclicity can be complex; nevertheless, recognizable patterns in earthquake recurrence emerge from long, high resolution, spatially distributed chronologies. Researchers now seek to discover the range of possible rupture areas, the variability of recurrence intervals, and patterns of earthquake clustering in space and time. The term “supercycle” has been used to describe repeating longer periods of strain accumulation and release that each involve multiple fault ruptures. However, this term has become very broadly applied, lumping together several distinct phenomena that have different implications for seismic hazard and fault mechanics. We welcome submissions regarding observations or models of any type of earthquake cyclicity but encourage authors to describe the behavior more specifically. We likewise invite submissions regarding rupture segmentation, i.e., limits placed on earthquake rupture areas by persistent, frequent, or ephemeral barriers, including connections between barrier behavior and underlying causes such as geologic structure or fault rheology.


T050 Subduction Top to Bottom 2 (ST2B-2): Processes and Products Modern and Ancient

Conveners: Gray E Bebout (Lehigh University), David William Scholl (University of Alaska Fairbanks), Robert J Stern (Univ Texas Dallas), Laura Wallace (University of Texas)

Abstract: From top-to-bottom, many geological, geophysical, petrologic/geochemical, and theoretical advancements have been made toward understanding subduction zone processes and dynamics. The term “subduction” was introduced in its modern sense in 1970 and the 1996 AGU Geophysical Monograph “Subduction Top to Bottom” marked a milestone in our understanding by capturing 26 years of early advances. This “Subduction Top to Bottom 2” (ST2B-2) session and a related themed issue in the GSA journal GEOSPHERE (now at more than 60 papers and growing) revisit these issues and re-assess them in light of recent advancements as well as explore new discoveries and advances in subduction zone research. We invite the broadest possible range of contributions, including abstracts considering subduction-related hazards, climate effects, and resources. We encourage presentations regarding processes at modern subduction zones and evidence of ancient subduction yielding insight regarding Earth plate tectonic evolution and processes at depth in modern margins.

T051 – Subduction Zone Observation through Time and Space: Path to an SZ4D Initiative on the Science of Subduction Hazards

Conveners: Harold J Tobin (University of Washington), George E Hilley (Stanford University), Diana C. Roman (Carnegie Institution for Science), Emily E Brodsky (University of California Santa Cruz)

Abstract: Subduction zone processes produce volcanic unrest, megathrust earthquakes, and shape land- and seascapes associated with plate convergence over seconds to millions of years. New technologies, including ocean-bottom and conventional seismometer networks, on- and off-shore geodetic networks, high-resolution imaging of subduction zone geomorphology, continuous multi-parameter instrumentation of volcanoes, as well as novel geochronologic, paleoseismologic, and geologic approaches, will all be critical to advancing new discoveries. At the same time, new modeling capabilities that integrate geologic and geophysical observations will be required to understand them and to develop and test hypotheses about subduction zone processes spanning human and geologic time scales. Submissions that highlight present and emerging observational capability, data acquisition, and modeling across a wide range of disciplines are welcomed. The session will also explore new research directions that promise to produce substantial advances in our holistic understanding and forecasting of subduction-related hazards in the coming decade.


T059 – The tectonic fabric of the seafloor: Propagators, microplates and beyond

Conveners: Brook Tozer (Scripps Institution of Oceanography), Vicki Ferrini  (Lamont-Doherty Earth Observatory), Paul Wessel (University of Hawaii), Ross Parnell-Turner (Scripps Institution of Oceanography)

Invited speakers: Suzanne Carbotte (Lamont-Doherty Earth Observatory), Aurore Sibrant (Université de Bretagne Occidentale)

Abstract: Seafloor mapping played a key role in the plate tectonic revolution, providing insights into the morphology, structure and age distribution of oceanic crust.  Decades of research has revealed the structure of mid-ocean ridges and fracture zones, as well as less prominent features such as propagating rifts and detachment faults. Such observations have helped us understand major geodynamic and geological processes and unravel the histories of entire ocean basins. Over the past 10y, the accuracy/resolution of satellite-derived seafloor and gravity anomaly maps has greatly improved, uncovering an abundance of “lower order” seafloor features which represent fundamental tectonic processes, but remain poorly understood. Moreover, high-resolution marine geophysical surveys continue to advance our understanding of many seafloor features/processes with unprecedented detail. We invite contributions focusing on observations and interpretation of seafloor features at local, regional or global scale and welcome studies which investigate previously poorly understood features by combining a variety of methodologies.


V008. Boom, Zap, and Roar: Multi-disciplinary characterization of volcanic explosion, jet, and plume dynamics

Conveners: Kathleen F McKee (Carnegie Institution for Science Washington), Sonja A Behnke (University of South Florida Tampa), Mary Benage (USGS Cascades Volcano Observatory), Benjamin James Andrews (Smithsonian Institution)

Abstract: Explosive volcanic eruptions generate highly electrified, multi-phase momentum-driven fluid flows (jets) that can transform into buoyant plumes. Understanding the dynamics of these systems is critical for forecasting eruption behavior and interpreting geophysical and visual observations of the jets and plumes. Unfortunately, these eruptions present numerous hazards and the interiors of the jets and plumes are obscured from direct observation. In this session we welcome submissions that discuss the dynamics of explosive eruption processes from generation to cessation with particular foci on processes that occur in the jet and plume, such as how lightning manifests in a jet or plume, particle concentration gradients and aggregation, turbulent structures, etc. We are particularly interested in studies that use field observations (e.g., seismicity, infrasound, gas, visible, infrared, and UV imagery, lightning, radar, deformation), laboratory and analog experiments, and/or physics-based modeling.

V012. Chemical and mechanical processes at plate margins: insights from the exhumed rock record

Conveners: Kayleigh Harvey (University of Maryland), Cailey Condit (Massachusetts Institute of Technology), Andrew Smye (Penn State University)

Abstract: Plate boundaries are the sites of complex feedbacks between chemical and physical petrogenetic processes. Heat and mass transfer and deformation promote metamorphism and magmatism, which in turn lead to changes in rock strength. These strongly-coupled processes influence the timescales and pathways of mass transport, the expression of deformation, and the crust’s rheologic evolution. Exhumed rocks provide the only direct means to investigate these processes and can ultimately inform geophysical, geodynamic and geochemical experiments and models. In this session, we invite contributions that utilize the metamorphic and magmatic rock records to investigate physical and chemical processes at plate margins. In particular, we encourage submissions that apply novel approaches to tackle outstanding questions, including but not limited to: chemo-mechanical evolution from the shallow to deep lithosphere, the roles of fluids in metamorphic, metasomatic and magmatic processes and rheologic changes in rocks, and mechanisms, rates and pathways of mass and heat transport.

V015. CONVERSE: Community Network for Volcanic Eruption Response – Coordination to Detect Eruption Precursors, and Respond to Volcanic Unrest and Eruptions

Conveners: Tobias P Fischer (University of New Mexico Main Campus), Michelle L Coombs (U.S. Geological Survey), Einat Lev (Lamont-Doherty Earth Observatory), Paul J Wallace (University of Oregon)

Abstract: Volcanic eruptions are common phenomena and more than 50 volcanic eruptions have occurred in the US alone in the past 31 years. These eruptions can have devastating economic and social consequences. Many volcanic eruptions have precursory signals that last from days to months while the actual eruptive events can last several years or decades. Precursory signals, such as heightened seismicity, subtle changes in gas emissions, and ground deformation, can be detected when adequate ground- and satellite- based observations are available. Observations and samples obtained during run-up and eruption have great potential for providing key scientific insights into the physical and chemical processes that drive eruptions, and obtaining them requires careful planning and coordination within the volcanological community. We encourage submissions that describe successful scientific responses to past eruptions, detection of eruption precursors, and ideas for what future responses could and should look like.
V026. Interactions between Magmatism, Tectonics, and Faulting in Rifts, Arcs, Ridges, Calderas, and Volcanic Fields

Dear colleagues,
We wish to invite you contributing your AGU Fall Meeting abstract to the following session focusing on magma-tectonic interactions:

Conveners: Christelle Wauthier (Pennsylvania State University), James Muirhead (Syracuse University), Joël Ruch (University of Geneva), and Sarah Jaye Oliva (Tulane University)

Abstract: Interactions between magmatism, tectonics, and faulting occur at different temporal and spatial scales, as they are observed from individual volcanoes to plate boundaries, during single eruptive events or over centuries. However, our current understanding is still limited due to a lack of integrated approaches. Field, geodetic, and modeling studies suggest that earthquakes can trigger volcanic eruptions and intrusions through static and dynamic stress transfer. Conversely, magmatic activity can generate earthquakes via stress changes in surrounding country rock. In rifting events, magmatic fluids can release tectonic stresses and also be influenced by pre-existing fracture zones. Finally, the combined effects of magmatic, gravitational, and tectonic stresses can trigger caldera and volcano flank collapse. We strongly encourage multidisciplinary studies integrating geodesy, structural geology, volcanology, geochemistry, seismology, stress analysis, and/or modeling (numerical and analogical) to decipher relationships between magmatic, tectonic, and faulting processes at different temporal and spatial scales.
We are looking forward to seeing you in San Francisco!

Christelle Wauthier, James Muirhead, Joël Ruch, and Sarah Jaye Oliva
V027. Izu-Bonin-Mariana arc system: synthesis and remaining questions

Conveners: Susan DeBari (Western Washington University), Shuichi Kodaira (Yokohama National University), Julie Prytulak (Imperial College London), Geoff Wheat (NURP/University of Alaska)

Abstract: The Izu-Bonin-Mariana (IBM) system is arguably the best-studied example of an intra-oceanic arc. The region has been a primary focus of subduction factory studies for several decades. From 2014-2017, four International Ocean Discovery Program (IODP) cruises further explored this arc system, with drilling sites in the Izu forearc (subduction initiation), Izu reararc (arc evolution), west of the Kyushu-Palau remnant arc ridge (arc origins), and the Mariana forearc (serpentinite mud volcanoes). Proposals for future IODP drilling in the region are still being submitted. This session aims to highlight recent developments in IBM subduction zone studies resulting from these concentrated multi-disciplinary studies. We invite papers on subduction initiation, the formation and evolution of arc magmas and arc crust, volcanology and arc cyclicity, geochemical cycling, deep biosphere activity, geophysical structure, slab dynamics, mantle flow, and modeling studies. We also welcome papers on outstanding scientific questions that can be addressed in the IBM system.

V040. Rates and timescales of magmatic processes recorded in minerals

Conveners: Thomas Shea (SOEST), Guilherme A R Gualda (Vanderbilt University), Madison Myers (Montana State University), Daniel J. Rasmussen (Lamont -Doherty Earth Observatory)

Are your crystals ticking…and would you like to talk about it? Determining rates of magmatic processes remains a major goal and challenge of magmatology and volcanology. Join us to talk about the processes and timescales your minerals are recording and consider submitting an abstract to our AGU session: V040 – Rates and timescales of magmatic processes recorded in minerals

Invited Speakers: Kendra Lynn (University of Delaware), Nathan Andersen (University of Oregon)

Abstract: Magmatic journeys involve complex processes and reactions occurring at timescales of seconds to hundreds of thousands of years, depending on local conditions (T, P, fO2). Chemical zoning in minerals provides an essential but variably incomplete record of these processes and their relevant conditions. Correlating mineral zoning across entire populations thus becomes critical to disentangling their magmatic history, particularly as frequent transfer of mineral cargo between magmas complicates this record. Each mineral also serves as a time capsule, containing elements that diffuse at different rates. Durations spanning the entire lifecycle of a magma can therefore potentially be resolved. In turn, radiometric dating provides absolute age control, a critical time stamp to assess their longevity in magma bodies. This session welcomes contributions leveraging chemical zoning and crystal clocks of any type to investigate the evolution of magmatic systems. We encourage efforts that marry theoretical, analytical, experimental, numerical, and geophysical approaches.


S002 – Centennial: One Hundred Years of Seismology

Through this session the Seismology Section will mark AGU’s centennial by considering 100 years of seismology. We welcome contributions that are both retrospective and prospective. The goal of the session is to first summarize important achievements in seismology over the past century, since the founding of AGU. We will complement that with predictions for the future based on current research trends, or more speculative visions, of key directions in seismology during the next 100 years. For the prospective component of the session, we are particularly interested in the perspective of early career scientists, and scientists in disciplines allied to seismology.
S003 – Centennial Session: Forensic Seismology, Origins and Future

In honor of AGU’s centennial, this session focuses on historical, current and future geophysical contributions in the fields of forensic seismology and global security. We invite submissions detailing seismic, acoustic, hydroacoustic, and other multiphenomenological research relevant to explosion monitoring, forensics, and other global security topics. Submissions highlighting leading contributors and breakthrough discoveries within the verification regime are also of interest. Colleagues and/or former students of influential contributors are encouraged to submit abstracts to present historical context on the origins of forensic seismology, it’s influence in shaping public policy related to global security and the field’s contributions to a broader scientific understanding within the fields of seismology and tectonics.
S004 – Centennial: The Anisotropic Earth

Seismic anisotropy has proven to be a vital constraint in characterizing the dynamic and tectonic processes that have shaped the Earth. Because of the fundamental importance in fully characterizing the amount and orientation of anisotropy as it relates to dynamic processes, numerous seismic analysis techniques have been developed and implemented. Significant work in laboratory experiments has helped illuminate the relationship between deformation, mineralogy, and seismic anisotropy. This session aims to highlight the modern advances made in the application and methodology of the analysis of seismic anisotropy as a tool to better understand our planet by highlighting advancements in seismological techniques from full-waveform modeling, receiver functions, shear wave splitting, surface waves, normal modes, and more. We encourage contributions spanning all depths from the inner core to the crust. We will look back at the field of seismic anisotropy as well as consider the future by emphasizing novel methods and modern advancements.


S012. Earthquakes Related Cascading Hazards

Conveners: Shanshan Li (Florida International University), Zhigang Peng (Georgia Tech), Shimon Wdowinski (Florida International University), Philippe Steer (University of Rennes 1, France)

Abstract: It is now well established that earthquakes can trigger or be triggered by other natural processes, including other earthquakes, landslides, tsunami, ice movement, volcanism, and extreme weather events and other cyclic forces such as tides, annual variations in atmospheric pressures and ground waters. However, identifying and understanding the physical mechanism, frequency, time delays and control factors of different earthquake related triggering relationships remains challenging. In this session, we welcome contributions that address, quantify, compare and model triggering relationships between earthquakes and between earthquakes and other natural hazards observed over timescales ranging from seconds to years in different tectonic regions. We aim to provide a platform for discussing potential earthquake-related triggering mechanisms and explore potential impacts of earthquakes and other natural hazards. We hope this session can provide new insights for estimating the likelihood of future damaging earthquakes and other natural hazards.

OS022. Marine Geohazards

Conveners: Derek Sawyer, Brandon Dugan, Jenna Hill, and Danny Brothers

Abstract: Marine geohazards are sudden and extreme geologic events that affect coastal areas and seabed infrastructure on local, regional, and transoceanic scales. The hazards include submarine earthquakes, explosive volcanic eruptions and collapses of volcanic edifices, submarine slope failures, and tsunami generation. The sediment record of past offshore and coastal hazardous events is often better preserved in the marine/ lacustrine environment than on land and can be investigated in great detail with high-resolution geological and geophysical tools. We seek contributions that highlight new results and methodologies in marine paleoseismology, submarine landslide studies, tsunami generation and volcanic eruptions. We also emphasize studies that span the major process domains (e.g., the shoreline and the shelf-edge) of both active and passive continental margins, studies that provide constraints on recurrence intervals for hazardous events, and studies that link fundamental geological processes to the assessment of marine geohazards.
OS025. Submarine Canyons, Channels, and Processes That Shape the Seafloor

Conveners: Katherine L Maier (National Institute of Water and Atmospheric Research), Jamie Howarth (Victoria University of Wellington), Jingping P. Xu (Southern University of Science and Technology), Michael Andrew Clare (University of Southampton)

Abstract: Submarine canyons and channels feed vast amounts of sediment and organic carbon into the deep sea via flows that shape the seafloor. These sediment transport processes, and resulting geomorphology and stratigraphy, can record tectonic, paleoclimatic, paleoseismic, and paleoceanographic changes, pose hazards for seafloor infrastructure, provide benthic habitats, and introduce nutrients and contaminants to ecosystems. Recent studies and technological advances have propelled our ability to link flows with deposits and morphological change, particularly through instrumental and seafloor observations and high-resolution imaging. We encourage multidisciplinary contributions from the full range of submarine canyon, channel, and turbidity current studies, from how sediment enters canyons to distal submarine fans. Contributions may include measurements of turbidity currents and internal tides, quantification of surficial features and morphologic change through seafloor mapping and observation, stratigraphic architecture from subsurface and outcrop datasets, geochemical analysis of deep-sea sediments and organic carbon, as well as physical and numerical modelling.
G012. Plate Motion, Continental Deformation, and Interseismic Strain Accumulation

Conveners: Donald F Argus (Jet Propulsion Laboratory), Jeffrey Todd Freymueller (Alaska Volcano Observatory Fairbanks), Rui Manuel Silva Fernandes (University of Beira Interior), D. Sarah Stamps (Massachusetts Institute of Technology)

Abstract: We seek studies examining the take up of plate motion in deforming zones and the buildup and release of elastic strain along major faults and in subduction zones using space geodetic measurements, geologic observations, and geophysical data such as seismicity, marine magnetic anomalies, and transform fault azimuths. How can GPS and InSAR be integrated to determine deformation in plate boundary zones? To what extent can observed elastic strain buildup and past earthquakes be used to infer the likelihood of future earthquakes? Are fault slip rates from paleoseismology identical to those from geodetic data? What fraction of plate motion is taken up by fault slip during earthquakes, and what fraction becomes part of distributed deformation off the major faults? How fast are mountains currently rising? To what degree do postseismic transients alter the nearly constant velocity of the plates, and how can postseismic transients influence the definition of Earth’s reference frame?
MR005 – Carbon and Hydrogen in the Deep Earth

Conveners: Cara Vennari (University of California Santa Cruz), Elizabeth Colette Thompson (University of Chicago), Natalia V Solomatova (Ecole Normale Supérieure Lyon), Lars N Hansen (University of Oxford)

Abstract: Carbon and hydrogen both play significant roles in the physical, petrological, geochemical, and geodynamic processes that shape our planet. Yet despite their importance, the degree and mechanisms of the cycling of these volatiles between Earth’s surface and interior remains an area of open inquiry, as is the long-term accommodation (i.e., storage) of carbon and hydrogen in the deep Earth. This session aims to unite researchers from the fields of seismology, geodynamics, petrology, geochemistry, and mineral physics, who actively investigate the role of carbon and hydrogen in Earth’s interior. Relevant topics include, but are not limited to: investigations into the origin, cycling, and fractionation of carbon and hydrogen; seismic and geodynamic studies of their influence in the deep Earth; and experimental and theoretical constraints on the structure, stability, and physical properties of carbon- and hydrogen-bearing phases at extreme conditions.

MR028. Rock Damage in Fault Zones

Dear all,

We would like to bring to your attention the following session at the 2019 AGU meeting in San Francisco entitled “Rock Damage in Fault Zones (MR028)”. We are looking to attract scientists who study deformation along and off-fault using field, numerical, experimental and observational approaches.

Conveners: François Renard (University of Oslo), Sarah Incel (Ruhr University, Bochum), Giulio di Toro (University of Padova), Yehuda Ben.-Zion (University of Southern California)

Confirmed invited speakers: Frans Aben (Univercity College, London), Bjørn Jamtvei (University of Oslo)

Abstract: Rock damage in fault zones is observed in many continental regions and is inferred in subduction zones. The damage modifies earthquake rupture properties and the evolution of seismic sequences. Geophysical data indicate km-wide damage zones along plate boundaries in the upper crust, while observations of fossil earthquakes show narrow cm-thick damage zones in the lower crust. In laboratory experiments, the evolution of damage with increasing stress leads to localization, and both slow and fast slips generate damage. The similarities and differences between shallow damage (upper few km) and deep damage (>20 km deep) from microstructures, mineral composition, lithology and geophysical observations are subject to considerable recent studies. This session aims to discuss why and how fault damage zones form and evolve across the entire crust. We encourage multi-disciplinary contributions from geological, geophysical, experimental, and modelling studies of fault damage, including novel techniques to extract information from large data sets.