Year-2017


Sep 17

A unified continental thickness from seismology and diamonds suggests a melt-defined plate

BY SAIKIRAN THARIMENA, CATHERINE RYCHERT, NICHOLAS HARMON

SCIENCE11 AUG 2017 : 580-583


Reflection seismology constrains continental lithosphere thickness, which is likely tied to small amounts of melt.


Seismic evidence for partial melting at the root of major hot spot plumes

BY KAIQING YUAN, BARBARA ROMANOWICZ

SCIENCE28 JUL 2017 : 393-397


Seismic tomographic methods detect a region of partially molten material in the root of Iceland’s mantle plume.




April 28
Complex multifault rupture during the 2016 Mw 7.8 Kaikōura earthquake, New Zealand

BY IAN J. HAMLING, SIGRÚN HREINSDÓTTIR, KATE CLARK, JOHN ELLIOTT, CUNREN LIANG, ERIC FIELDING, NICOLA LITCHFIELD, PILAR VILLAMOR, LAURA WALLACE, TIM J. WRIGHT, ELISABETTA D’ANASTASIO, STEPHEN BANNISTER, DAVID BURBIDGE, PAUL DENYS, PAULA GENTLE, JAMIE HOWARTH, CHRISTOF MUELLER, NEVILLE PALMER, CHRIS PEARSON, WILLIAM POWER, PHILIP BARNES, DAVID J. A. BARRELL, RUSS VAN DISSEN, ROBERT LANGRIDGE, TIM LITTLE, ANDREW NICOL, JARG PETTINGA, JULIE ROWLAND, MARK STIRLING

SCIENCE14 APR 2017

FULL ACCESS

At least 12 faults spaced up to 15 kilometers apart ruptured during the magnitude 7.8 Kaikōura earthquake.


Imaging the distribution of transient viscosity after the 2016 Mw 7.1 Kumamoto earthquake

BY JAMES D. P. MOORE, HANG YU, CHI-HSIEN TANG, TENG WANG, SYLVAIN BARBOT, DONGJU PENG, SAGAR MASUTI, JUSTIN DAUWELS, YA-JU HSU, VALÈRE LAMBERT, PRIYAMVADA NANJUNDIAH, SHENGJI WEI, ERIC LINDSEY, LUJIA FENG, BUNICHIRO SHIBAZAKI



The combination of GPS and InSAR data after the Kumamoto earthquake in Japan allows for an estimate of regional rock rheology.





Experimental constraints on the damp peridotite solidus and oceanic mantle potential temperature

BY EMILY SARAFIAN, GLENN A. GAETANI, ERIK H. HAURI, ADAM R. SARAFIAN

SCIENCE03 MAR 2017 : 942-945


Experiments on mantle rock with small amounts of water provide constraints on the temperature of Earth’s mantle.


Planet Earth to get a daily selfie

BY MARK STRAUSS

SCIENCE24 FEB 2017 : 782-783


Researchers await data from the satellite company Planet, which has launched a flotilla of tiny eyes in the sky that will soon image the entire globe every day.


Volcanic tremor and plume height hysteresis from Pavlof Volcano, Alaska

BY DAVID FEE, MATTHEW M. HANEY, ROBIN S. MATOZA, ALEXA R. VAN EATON, PETER CERVELLI, DAVID J. SCHNEIDER, ALEXANDRA M. IEZZI

SCIENCE06 JAN 2017 : 45-48

FULL ACCESS

The seismic and infrasonic volcanic tremors track ash plume height from the 2016 eruption of Pavlof Volcano.




Year - 2016


Fault activation by hydraulic fracturing in western Canada

BY XUEWEI BAO, DAVID W. EATON

SCIENCE16 DEC 2016 : 1406-1409


Hydraulic fracturing reactivated faults, inducing an earthquake of magnitude > 4 in western Canada.


Mega-earthquakes rupture flat megathrusts

BY QUENTIN BLETERY, AMANDA M. THOMAS, ALAN W. REMPEL, LEIF KARLSTROM, ANTHONY SLADEN, LOUIS DE BARROS

SCIENCE25 NOV 2016 : 1027-1031


Large earthquakes in subduction zones are most likely to occur where the subducting slab is relatively flat.


Coseismic rupturing stopped by Aso volcano during the 2016 Mw 7.1 Kumamoto earthquake, Japan

BY A. LIN, T. SATSUKAWA, M. WANG, Z. MOHAMMADI ASL, R. FUETA, F. NAKAJIMA

SCIENCE18 NOV 2016 : 869-874

The Aso volcanic cluster stopped the fault rupture responsible for the 2015 magnitude 7.1 Kumamoto earthquake.


Localized seismic deformation in the upper mantle revealed by dense seismic arrays

BY ASAF INBAL, JEAN PAUL AMPUERO, ROBERT W. CLAYTON

SCIENCE07 OCT 2016 : 88-92 


Dense seismic arrays detect localized earthquakes that may track rock deformation in the ductile region of Earth.



High-resolution lithosphere viscosity and dynamics revealed by magnetotelluric imaging

BY LIJUN LIU, DERRICK HASTEROK

SCIENCE30 SEP 2016 : 1515-1519 




Deeper penetration of large earthquakes on seismically quiescent faults

BY JUNLE JIANG, NADIA LAPUSTA

SCIENCE10 JUN 2016 : 1293-1297


Reduced seismicity along certain strike-slip fault segments may be due to unexpectedly deep ruptures during big earthquakes.


• Editor's Summary  Abstract  Full Text  PDF


Connecting slow earthquakes to huge earthquakes

BY KAZUSHIGE OBARA, AITARO KATO


SCIENCE15 JUL 2016 : 253-257



Teleseismic S wave microseisms

BY KIWAMU NISHIDA, RYOTA TAKAGI

SCIENCE26 AUG 2016 : 919-921

Detection of microseisms from a severe distant storm provides a new path for seismic structure determination.



Periodic slow slip triggers megathrust zone earthquakes in northeastern Japan

BY NAOKI UCHIDA, TAKESHI IINUMA, ROBERT M. NADEAU, ROLAND BÜRGMANN, RYOTA HINO

SCIENCE29 JAN 2016 : 488-492 

Earthquake-triggering slow-slip events occur quasi-periodically in northeast Japan.

 

Archean upper crust transition from mafic to felsic marks the onset of plate tectonics

BY MING TANG, KANG CHEN, ROBERTA L. RUDNICK

SCIENCE22 JAN 2016 : 372-375 

New geochemical proxies for MgO track the chemistry and evolution of Earth’s continental crust over 4 billion years.

 

Shear deformation of bridgmanite and magnesiowüstite aggregates at lower mantle conditions

BY JENNIFER GIRARD, GEORGE AMULELE, ROBERT FARLA, ANWAR MOHIUDDIN, SHUN-ICHIRO KARATO

SCIENCE08 JAN 2016 : 144-147 

Shearing experiments at lower mantle conditions show that the less abundant of the two major mantle minerals is easily deformed. [Also see Perspective by Chen]

 

Geomorphic and geologic controls of geohazards induced by Nepal’s 2015 Gorkha earthquake

BY J. S. KARGEL, G. J. LEONARD, D. et al.

SCIENCE08 JAN 2016 

Satellite imaging isolated hazard potential for earthquake-triggered landslides after the 2015 Gorkha earthquake in Nepal.

 

 

Year - 2015

Geophysical imaging reveals topographic stress control of bedrock weathering

BY J. ST. CLAIR, S. MOON, W. S. HOLBROOK, J. T. PERRON, C. S. RIEBE, S. J. MARTEL, B. CARR, C. HARMAN, K. SINGHA, D. DEB. RICHTER

SCIENCE30 OCT 2015 : 534-538 

Geophysical survey data and stress modeling connect surface topography to Earth’s critical zone. [Also see Perspective by Anderson]

 

Stress orientations in subduction zones and the strength of subduction megathrust faults

Science 11 September 2015: 1213-1216. 

Subduction zone faults are weak at depth, well-oriented for failure, and embedded in a low-stress environment.[Also see Perspective by Bürgmann]

 

Slip pulse and resonance of the Kathmandu basin during the 2015 Gorkha earthquake, Nepal

Science 4 September 2015: 1091-1095.

Published online 6 August 2015 [DOI:10.1126/science.aac6383]

Continuous GPS and InSAR measurements record slip on the fault responsible for the 2015 Mw 7.8 Gorkha earthquake in Nepal.

 

Layered deformation in the Taiwan orogen

Science 14 August 2015: 720-723. 

A change in the direction of deformation with depth helps explain subduction-driven uplift.[Also see Perspective by Long]

 

Sea-level rise due to polar ice-sheet mass loss during past warm periods

Science 10 July 2015: aaa4019 

Reconstructing past magnitudes, rates, and sources of sea-level rise can help project what our warmer future may hold.

 

High-rate injection is associated with the increase in U.S. mid-continent seismicity

Science 19 June 2015: 1336-1340. 

High injection rates of wastewater into deep wells increase the risk of earthquakes in regions prone to induced seismicity.

 

Seismicity triggered by fluid injection–induced aseismic slip

Science 12 June 2015: 1224-1226. 

Real-time observations of a reactivated fault provide an option for monitoring of earthquake-inducing wastewater injection.[Also see Perspective by Cornet]

 

Dynamic thinning of glaciers on the Southern Antarctic Peninsula

Science 22 May 2015: 899-903.
Glaciers on the Southern Antarctic Peninsula are disappearing at increasing rates.

 

Volume loss from Antarctic ice shelves is accelerating

Science 17 April 2015: 327-331.
Published online 26 March 2015 [DOI:10.1126/science.aaa0940]

 

Glacial cycles drive variations in the production of oceanic crust

Science 13 March 2015: 1237-1240.

Published online 5 February 2015 [DOI:10.1126/science.1261508]

Abstract Full Text Full Text (PDF) Supplementary Materials

 

Superplastic nanofibrous slip zones control seismogenic fault friction

o    Berend A. Verberne, Oliver Plümper, D.A. Matthijs de Winter, and Christopher J. Spiers

Science 12 December 2014: 1342-1344.[DOI:10.1126/science.1259003]

Nanogranular microstructures found in simulated carbonate faults control the physical sliding mechanism during rupture.

o    Abstract Full Text Full Text (PDF) Supplementary Materials

 

2014

Tectonic control of Yarlung Tsangpo Gorge revealed by a buried canyon in Southern Tibet

Ping Wang, Dirk Scherler, Jing Liu-Zeng, Jürgen Mey, Jean-Philippe Avouac, Yunda Zhang, and Dingguo Shi

Science 21 November 2014: 978-981.[DOI:10.1126/science.1259041]

Sediment cores from a buried canyon upstream of the Tsangpo Gorge support a rapid uplift event to explain gorge formation. [Also see Perspective by Whipple]

Abstract Full Text Full Text (PDF) Supplementary Materials

 

 

A large magmatic sill complex beneath the Toba caldera

·         K. Jaxybulatov, N. M. Shapiro, I. Koulakov, A. Mordret, M. Landès, and C. Sens-Schönfelder 

Science 31 October 2014 : 617-619. 

Ambient noise tomography images the magma distribution of a large volcanic reservoir under the Toba caldera.

·         Abstract   Full Text   Full Text (PDF)    Supplementary Materials

 

 

Ongoing drought-induced uplift in the western United States

·         Adrian Antal Borsa, Duncan Carr Agnew, and Daniel R. CayanScience 26 September 2014 : 1587-1590.
Published online 21 August 2014 [DOI:10.1126/science.1260279] 

GPS measurements of crustal rebound in the western U.S. quantify drought-induced regional water depletion.

·         Abstract   Full Text  Full Text (PDF)   Supplementary Materials

 

Intense foreshocks and a slow slip event preceded the 2014 Iquique Mw 8.1 earthquake

·         S. Ruiz, M. Metois, A. Fuenzalida, J. Ruiz, F. Leyton, R. Grandin, C. Vigny, R. Madariaga, and J. Campos 

Science 5 September 2014 : 1165-1169.
Published online 24 July 2014 [DOI:10.1126/science.1256074] 

The intense and anomalous seismicity preceding the mainshock was the final step of a slow slip event.

·         Abstract Full Text Full Text (PDF) Supplementary Materials

 

Strength of stick-slip and creeping subduction megathrusts from heat flow observations

·         Xiang Gao and Kelin Wang 

Science 29 August 2014 : 1038-1041. 

Megathrusts subducting rugged sea floor have high fault strength but do not unleash great earthquakes.

·         Abstract  Full Text Full Text (PDF) Supplementary Materials

 

Supershear rupture in a Mw 6.7 aftershock of the 2013 Sea of Okhotsk earthquake

Zhongwen Zhan, Donald V. Helmberger, Hiroo Kanamori, and Peter M. Shearer

Science 11 July 2014: 204-207.

Earthquakes that occur hundreds of kilometers below the surface may have more than one rupture mechanism.

Abstract   Full Text  Full Text (PDF) Supplementary Materials

 

Dehydration melting at the top of the lower mantle

·         Brandon Schmandt, Steven D. Jacobsen, Thorsten W. Becker, Zhenxian Liu, and Kenneth G. Dueker 

Science 13 June 2014 : 1265-1268. 

Downwelling of hydrous minerals may cause partial melting of Earth’s lower mantle.

·         Abstract  Full Text   Full Text (PDF)   Supplementary Materials

 

Melting of subducted basalt at the core-mantle boundary

·         Denis Andrault, Giacomo Pesce, Mohamed Ali Bouhifd, Nathalie Bolfan-Casanova, Jean-Marc Hénot, and Mohamed Mezouar 

Science 23 May 2014 : 892-895. 

Mid-ocean ridge basalt entrained in the lowermost mantle is consistent with seismic ultra–low velocity zones[Also see Perspective byWilliams]

·         Abstract   Full Text   Full Text (PDF)   Supplementary Materials

 

Geophysical and Geochemical Evidence for Deep Temperature Variations Beneath Mid-Ocean Ridges

·         Colleen A. Dalton, Charles H. Langmuir, and Allison GaleScience 4 April 2014 : 80-83. 

Temperature variations in the upper mantle drive mantle convection.[Also see Perspective byKelley]

·         Abstract  Full Text   Full Text (PDF)  Supplementary Materials

 

Changes in Seismic Anisotropy Shed Light on the Nature of the Gutenberg Discontinuity

·         Caroline Beghein, Kaiqing Yuan, Nicholas Schmerr, and Zheng XingScience 14 March 2014 : 1237-1240.
Published online 27 February 2014 [DOI:10.1126/science.1246724] 

The Gutenberg discontinuity is distinct from the lithosphere-asthenosphere boundary.

·         Abstract Full Text Full Text (PDF) Supplementary Materials

 

 2013

Low Coseismic Friction on the Tohoku-Oki Fault Determined from Temperature Measurements

·         P. M. Fulton, E. E. Brodsky, Y. Kano, J. Mori, F. Chester, T. Ishikawa, R. N. Harris, W. Lin, …

Science 6 December 2013 : 1214-1217. 

The Tohoku-Oki earthquake occurred along a thin, clay-rich fault zone in the basal strata of the subducting plate.

·         Abstract    Full Text   Full Text (PDF)   Supplementary Materials    Podcast Interview

 

 

Low Coseismic Shear Stress on the Tohoku-Oki Megathrust Determined from Laboratory Experiments

·         Kohtaro Ujiie, Hanae Tanaka, Tsubasa Saito, Akito Tsutsumi, James J. Mori, Jun Kameda, Emily E. Brodsky, … 

Science 6 December 2013 : 1211-1214. 

The Tohoku-Oki earthquake occurred along a thin, clay-rich fault zone in the basal strata of the subducting plate.

·         Abstract Full Text  Full Text (PDF)   Supplementary Materials

 

 

Structure and Composition of the Plate-Boundary Slip Zone for the 2011 Tohoku-Oki Earthquake

·         Frederick M. Chester, Christie Rowe, Kohtaro Ujiie, James Kirkpatrick, Christine Regalla, Francesca Remitti, J. Casey Moore, … 

Science 6 December 2013 : 1208-1211. 

The Tohoku-Oki earthquake occurred along a thin, clay-rich fault zone in the basal strata of the subducting plate.

·         Abstract   Full Text   Full Text (PDF)    Supplementary Materials

 

 

October 2013

Waveform Tomography Reveals Channeled Flow at the Base of the Oceanic Asthenosphere

"Understanding the relationship between different scales of convection that drive plate motions and hotspot volcanism still eludes geophysicists. Using full-waveform seismic tomography, we imaged a pattern of horizontally elongated bands of low shear velocity, most prominent between 200 and 350 kilometers depth, which extends below the well-developed low-velocity zone. These quasi-periodic fingerlike structures of wavelength ~2000 kilometers align parallel to the direction of absolute plate motion for thousands of kilometers. Below 400 kilometers depth, velocity structure is organized into fewer, undulating but vertically coherent, low-velocity plumelike features, which appear rooted in the lower mantle. This suggests the presence of a dynamic interplay between plate-driven flow in the low-velocity zone and active influx of low-rigidity material from deep mantle sources deflected horizontally beneath the moving top boundary layer."

Full Text       Full Text (PDF)       Supplementary Materials

 

 

September 2013

Energy Release of the 2013 Mw 8.3 Sea of Okhotsk Earthquake and Deep Slab Stress Heterogeneity

"Earth’s deepest earthquakes occur in subducting oceanic lithosphere, where temperatures are lower than in ambient mantle. On 24 May 2013, a magnitude 8.3 earthquake ruptured a 180-kilometer-long fault within the subducting Pacific plate about 609 kilometers below the Sea of Okhotsk. Global seismic P wave recordings indicate a radiated seismic energy of ~1.5 × 1017 joules. A rupture velocity of ~4.0 to 4.5 kilometers/second is determined by back-projection of short-period P waves, and the fault width is constrained to give static stress drop estimates (~12 to 15 megapascals) compatible with theoretical radiation efficiency for crack models. A nearby aftershock had a stress drop one to two orders of magnitude higher, indicating large stress heterogeneity in the deep slab, and plausibly within the rupture process of the great event."

 

Deep-Focus Earthquake Analogs Recorded at High Pressure and Temperature in the Laboratory

"Phase transformations of metastable olivine might trigger deep-focus earthquakes (400 to 700 kilometers) in cold subducting lithosphere. To explore the feasibility of this mechanism, we performed laboratory deformation experiments on germanium olivine (Mg2GeO4) under differential stress at high pressure (P = 2 to 5 gigapascals) and within a narrow temperature range (T = 1000 to 1250 kelvin). We found that fractures nucleate at the onset of the olivine-to-spinel transition. These fractures propagate dynamically (at anonnegligible fraction of the shear wave velocity) so that intense acoustic emissions are generated. Similar to deep-focus earthquakes, these acoustic emissions arise from pure shear sources and obey the Gutenberg-Richter law without following Omori’s law. Microstructural observations prove that dynamic weakening likely involves superplasticity of thenanocrystalline spinel reaction product at seismic strain rates."

 

Slow Earthquakes, Preseismic Velocity Changes, and the Origin of Slow Frictional Stick-Slip

"Earthquakes normally occur as frictional stick-slip instabilities, resulting in catastrophic failure and seismic rupture. Tectonic faults also fail in slow earthquakes with rupture durations of months or more, yet their origin is poorly understood. Here, we present laboratory observations of repetitive, slow stick-slip in serpentinite fault zones and mechanical evidence for their origin. We document a transition from unstable to stable frictional behavior with increasing slip velocity, providing a mechanism to limit the speed of slow earthquakes. We also document reduction of P-wave speed within the active shear zone before stick-slip events. If similar mechanisms operate in nature, our results suggest that higher-resolution studies of elastic properties in tectonic fault zones may aid in the search for reliable earthquake precursors."

 

August 2013

Mapping Tectonic Deformation in the Crust and Upper Mantle Beneath Europe and the North Atlantic Ocean

" We constructed a three-dimensional azimuthally anisotropic model of Europe and the North Atlantic Ocean based on adjoint seismic tomography. Several features are well correlated with historical tectonic events in this region, such as extension along the North Atlantic Ridge, trench retreat in the Mediterranean, and counterclockwise rotation of the Anatolian Plate. Beneath northeastern Europe, the direction of the fast anisotropic axis follows trends of ancient rift systems older than 350 million years, suggesting “frozen-in” anisotropy related to the formation of the craton. Local anisotropic strength profiles identify the brittle-ductile transitions in lithospheric strength. In continental regions, these profiles also identify the lower crust, characterized by ductile flow. The observed anisotropic fabric is generally consistent with the current surface strain rate measured by geodetic surveys. "

Full Text       Full Text (PDF)       Supplementary Materials