If Mineral Physics provides the eyes for seeing into the earth…

Seismology provides the ears…

Courtesy of J. Tromp

Nankai trench off the Izu Peninsula, Japan (Courtesy of UTexas, Jackson School of Geosciences)

KEY SEISMOLOGICAL PRACTICES : MULTISCALE 3D and 4D IMAGING AND MODELING OF COMPLEX EARTH SYSTEMS

KEY SEISMOLOGICAL PRACTICES : MULTISCALE 3D and 4D IMAGING AND MODELING OF COMPLEX EARTH SYSTEMS

Velocities at depth of a recent 3D S-wave velocity model (Courtesy of Kustowski et al.)

Rayleigh wave group velocities for 60,000 8-sec waves from 3 years of continuous data (Courtesy of Moschetti et al.)

KEY SEISMOLOGICAL PRACTICES: MULTISCALE 3D and 4D IMAGING AND MODELING OF COMPLEX EARTH SYSTEMS

EarthScope: Has provided a lot more ears over North America

Tomographic threshold

Scattered-wave threshold

Tectonic fault ruptures

Magmatic processesPetroleum reservoirsNuclear

explosions

Ice movementsGroundwater reservoirs

Geotechnical problemsEnvironmental

remediationSurface noise processes

Societal challenges for seismology are concentrated in the near-surface environment…

Crust

Upper mantle

Lower mantle

Core

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log

(dep

th in

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(Courtesy of Tom Jordan)

Topography of an exposed fault surface measured in Klamath Falls, Oregon (Courtesy of E. Brodsky)

GRAND CHALLENGE 1. HOW DO FAULTS SLIP?

Rupture process for the 2001 Kokoxili, Tibet, (Mw 7.8) earthquake (Courtesy of Walker and Shearer)

GRAND CHALLENGE 1. HOW DO FAULTS SLIP?

Rupture zones of the 26 December 2004 and 28 March 2005 great Sumatra earthquakes (Courtesy of C.J. Ammon)

GRAND CHALLENGE 1. HOW DO FAULTS SLIP?

Identifying repeat patterns of seismicity (Courtesy of Waldhauser and Schaff)

Sidebar 1: Seismicity

“AlertMap” test showing predicted distribution of ground shaking for the October 20, 2007, Mw 5.4 earthquake near San Jose (Courtesy of R. Allen)

Sidebar 2: Earthquake Rapid Warning Systems

Change of ground structure between seismic stations over time, measured from cross-correlation of microseismic noise (Courtesy of Brenguier et al.)

Sidebar 3: Ambient Noise and Fault Zone Healing

Tremor “event” in January, 2007, corresponding with slow slip of a few cm. Events repeat every 14 months (Courtesy of K.Creager)

Sidebar 4: Episodic Tremor and Slip (ETS)

San Gabriel and Los Angeles Basins showing soil structures as indicators of future shaking during an earthquake (Courtesy of Thelen et al.)

GRAND CHALLENGE 2. HOW DOES THE NEAR-SURFACE ENVIRONMENT AFFECT NATURAL HAZARDS AND RESOURCES?

Seismic cross section of a subsurface clay-bounded channel (center) containing a dense liquid contaminant (Courtesy of Gao et al.)

GRAND CHALLENGE 2. HOW DOES THE NEAR-SURFACE ENVIRONMENT AFFECT NATURAL HAZARDS AND RESOURCES?

Met

ers

Building devastation from the 2008 Wenchuan earthquake in China

Sidebar 5: Earthquake Prediction and Predictability

Sidebar 7: Underground Nuclear Explosion Monitoring and Discrimination

Seismic waves can distinguish explosions and implosions from earthquakes (“double couples”) (Courtesy of Dreger et al.)

Sidebar 8: Gas Hydrates as an Energy Source, Environmental Hazard, and a Factor in Global Climate Change

(Courtesy of Trehu et al.)

Plate boundary deformations, involving surface velocities, shear strains, and mean strains for the San Andreas System from geodetic measurements (Courtesy of Platt et al.)

GRAND CHALLENGE 3. WHAT IS THE RELATIONSHIP BETWEEN STRESS AND STRAIN IN THE LITHOSPHERE?

Tiny Montana earthquakes triggered by waves from the 2002 Mw 7.9 Denali Earthquake (Courtesy of Manga and Brodsky)

Sidebar 9: Remote Triggering of Earthquakes

Average sources of long period “hum” (Winter/Summer), compared to averaged wave heights from Topex/Poseidon (Courtesy of Rhie and Romanowicz)

GRAND CHALLENGE 4. HOW DO PROCESSES IN THE OCEAN AND ATMOSPHERE INTERACT WITH THE SOLID EARTH?

Infrasonic sources monitored across Europe using regional infrasound records for 2000-2007 (Courtesy of Le Pichon et al.)

GRAND CHALLENGE 4. HOW DO PROCESSES IN THE OCEAN AND ATMOSPHERE INTERACT WITH THE SOLID EARTH?

Greenland events associated with outflow of major continental glaciers (Courtesy of Ekström et al.)

Sidebar 11: Cryoseismology

Imaging fine-scale (5m resolution) features of ocean layers, revealing thermohaline circulation eddies (Courtesy, S. Holbrook)

Sidebar 12: Seismic Imaging of Ocean Structure

4D seismic imaging of reservoirs can show the changing locations of hydrocarbons as they are extracted (Courtesy of J. Louie)

GRAND CHALLENGE 5. WHERE ARE WATER AND HYDROCARBONS HIDDEN BENEATH THE SURFACE?Sidebar 13: Exploration Seismology and Resources: Energy and Mining

Ex/ CO2 injection (8 Mton) at the Sleipner field in the Norwegian North Sea (Courtesy of Chadwick et al.)

Sidebar 15: Four-Dimensional Imaging of Carbon Sequestration

GRAND CHALLENGE 6. HOW DO MAGMAS ASCEND AND ERUPT?

Slices from a 3D image of Okmok Volcano, Alaska

Ratio of P/S velocities in the Nicaraguan subduction zone; Dark red areas show presence of rising melts from water dehydration (Courtesy of Syracuse et al.)

GRAND CHALLENGE 6. HOW DO MAGMAS ASCEND AND ERUPT?

Ex/ Changing seismic velocity just before the 1999 (left) and 2006 (right) eruptions of Piton de la Fournaise volcano (Reunion) (Courtesy of Brenguier et al.)

Sidebar 16: Four-Dimensional Monitoring of Volcanoes Using Ambient Seismic Noise

GRAND CHALLENGE 6. HOW DO MAGMAS ASCEND AND ERUPT?

Seismic velocity discontinuities beneath the Sierra Nevada, suggesting detachment of lower crust (continental lithosphere is more complex than we realized) (Courtesy of Gilbert et al.)

GRAND CHALLENGE 7. WHAT IS THE LITHOSPHERE-ASTHENOSPHERE BOUNDARY?

Example of seismically imaged ancient continental lithospheric sutures, persisting to the present (Courtesy of M. Bostock)

GRAND CHALLENGE 7. WHAT IS THE LITHOSPHERE-ASTHENOSPHERE BOUNDARY?

Seismic velocity contrasts associated with the lithosphere-asthenosphere boundary under New England are too sharp for just temperature (hydrated? melt?) (Courtesy of Rychert et al.)

GRAND CHALLENGE 7. WHAT IS THE LITHOSPHERE-ASTHENOSPHERE BOUNDARY?

Intraplate seismicity of New Madrid seismic zone superimposed on map of topography (Courtesy of M.B. Magnani)

Sidebar 17: Intraplate Earthquakes

GRAND CHALLENGE 7. WHAT IS THE LITHOSPHERE-ASTHENOSPHERE BOUNDARY?

Map of diffuse plate boundary regions (Updated from Gordon and Stein)

GRAND CHALLENGE 8. HOW DO PLATE BOUNDARY SYSTEMS EVOLVE?

Seismic tomography of upper 1000 km beneath Western US showing disruption of subducting Juan de Fuca plate by upwelling plume (Courtesy of R. Allen)

GRAND CHALLENGE 8. HOW DO PLATE BOUNDARY SYSTEMS EVOLVE?

Ex/ The Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) images the interface between the subducting Philippine Plate and overriding continental plate, examining conditions for seismic/aseismic slip

Sidebar 18: Plate Boundary Field Laboratories

Aftershocks of deep earthquakes can rupture outside of the seismically active cores of deep slabs, perhaps due to transient high strain rates (Courtesy of D. Wiens)

Sidebar 19: Deep Earthquakes

GRAND CHALLENGE 8. HOW DO PLATE BOUNDARY SYSTEMS EVOLVE?

Global 3D configuration of seismic velocity heterogeneities in the mantle as imaged by seismic tomography (Courtesy of A. Dziewonski)

GRAND CHALLENGE 9. HOW DO TEMPERATURE AND COMPOSITION VARIATIONS CONTROL MANTLE AND CORE CONVECTION?

Seismic sampling of the sub-African superplume? Megaplume? Megapile? LLSVP! (Courtesy of Wang and Wen)

GRAND CHALLENGE 9. HOW DO TEMPERATURE AND COMPOSITION VARIATIONS CONTROL MANTLE AND CORE CONVECTION?

3D distribution of anisotropic fabric within the outer part of inner core; there is unusual east-west variation in velocity, attenuation, and anisotropy (Courtesy of X. Song)

Sidebar 20: The Mysterious Inner Core

Buzz Aldrin deploying a seismometer on the Moon during the Apollo 11 mission; seismometers are planned for future missions to both Mars and the Moon (Courtesy of NASA)

Sidebar 21: Planetary Seismology

GRAND CHALLENGE 9. HOW DO TEMPERATURE AND COMPOSITION VARIATIONS CONTROL MANTLE AND CORE CONVECTION?

Topography on three major Earth boundaries at and beneath South America, showing the dominating effects of subduction (Courtesy of N. Schmerr)

GRAND CHALLENGE 10. HOW ARE EARTH’S INTERNAL BOUNDARIES AFFECTED BY DYNAMICS?

Cross sections in a 3D seismic migration image of S-wave reflectivity in the mantle wedge adjacent to subducting Tonga slab; quasihorizontal structures not explained by standard petrological models (Courtest of Y. Zheng)

GRAND CHALLENGE 10. HOW ARE EARTH’S INTERNAL BOUNDARIES AFFECTED BY DYNAMICS?

Migrated S-wave reflector images of the core-mantle boundary (Courtesy of van der Hilst et al.)

GRAND CHALLENGE 10. HOW ARE EARTH’S INTERNAL BOUNDARIES AFFECTED BY DYNAMICS?

The transition from perovskite to post-perovskite. (Courtesy of Hernlund et al.)

Sidebar 22: Core-Mantle Boundary Heat Flow

GRAND CHALLENGE 10. HOW ARE EARTH’S INTERNAL BOUNDARIES AFFECTED BY DYNAMICS?