Article
Geosciences, Multidisciplinary
Nahidul Hoque Samrat, Matt A. King, Christopher Watson, Andrea Hay, Valentina R. Barletta, Andrea Bordoni
Summary: Through GPS observations and digital elevation models, the study demonstrates that the rheology and ice-mass change in the northern Marguerite Bay region of the Antarctic Peninsula are influenced by viscoelasticity, and the non-linear uplift phenomenon can be explained by a layered viscoelastic model.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geochemistry & Geophysics
Guangyu Xu, Yangmao Wen, Yaning Yi, Zelong Guo, Leyang Wang, Caijun Xu
Summary: On November 4, 2015, a M-w 6.5 earthquake occurred in the eastern region of Alor Island, eastern Indonesia. In this study, Sentinel-1 and ALOS-2 data were used to analyze the coseismic surface displacement of the earthquake. The findings revealed a previously unknown fault and provided the fault model and coseismic slip distribution of the 2015 Alor earthquake, indicating a south-southeast striking, south-southwest dipping strike-slip fault with a normal slip component and a peak slip of 2.09 m at a depth of 2.34 km.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
Changda Yan, Shin'ichi Miyazaki
Summary: A new method using a non-linear power-law rheology earth model was proposed for modelling post-seismic gravity change. Simulations and calculations demonstrated the potential of this method in explaining rapid gravity changes after earthquakes.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
S. Barbot, J. R. Weiss
Summary: The Eastern Mediterranean region is the most seismically active in Europe, with complex interactions between the Arabian, African, and Eurasian tectonic plates. A kinematic model based on geodetic observations shows that viscoelastic flow dominates deformation in Anatolia, with slab pull occurring in western Turkey, the Aegean Sea, and Greece. The study highlights the competing roles of different tectonic mechanisms in accommodating regional surface deformation in the Eastern Mediterranean.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
Jianfeng Yang, Liang Zhao, Yang Li
Summary: Fluids associated with subducting slabs play a crucial role in regulating water discharge, arc magmatism, and intermediate-depth earthquakes. This study presents high-resolution numerical models that show the impact of plastic weakening and friction coefficient on fault patterns, while plate age and elasticity have minimal influence. Brittle bending faults facilitate seawater infiltrating into subducting slabs, explaining sporadic lower plane earthquakes.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
Lawrence M. Cathles, Willy Fjeldskaar, Aleksey Amantov
Summary: This paper presents a new analytical method for inferring the elastic and viscous properties of the lithosphere and upper mantle based on uplift rate and history. The method is mathematically described and demonstrated through the analysis of isostatic adjustment in areas affected by glaciation. It replicates published conclusions, provides insights from literature, and offers new ways to separate the impacts of the lithosphere and asthenosphere on uplift rates.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
Sambuddha Dhar, Jun Muto, Yoshiaki Ito, Satoshi Miura, James D. P. Moore, Yusaku Ohta, Takeshi Iinuma
Summary: The Japan forearc is important in understanding post-seismic deformation, and recent studies have shown heterogeneity in the rheology of the forearc mantle. This study investigates the variation of the stagnant part of the mantle wedge across Japan and finds along-arc heterogeneity in the forearc mantle rheology.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geology
Vuong V. Mai, Jun Korenaga
Summary: Recent studies suggest that early Earth may have been a water world with few exposed continents. Unlike modern Earth, the thickness of early Earth's continents may have been controlled by the strength of the continental crust.
Article
Geochemistry & Geophysics
J. Martin de Blas, G. Iaffaldano, E. Calais
Summary: According to the observation results of space geodetic techniques, the rigid motion of the whole Anatolian microplate was altered by the stress released during the 1999 Izmit-Duzce earthquakes. This challenges the current plate tectonics paradigm assumption that relative plate motions remain unperturbed by temporal stress changes during the seismic cycle.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geochemistry & Geophysics
Congmin Wei, Guojie Meng, Weiwei Wu, Tai Liu, Weipeng Ge, Xueliang Chen, Guoqiang Zhao, Tian He
Summary: This study investigates the spatiotemporal evolution of crustal deformation caused by the 2008 Wenchuan earthquake and its impact on nearby active faults using GPS observations. The results show that post-seismic deformation is asymmetrically distributed on both sides of the Longmenshan fault and decreases with increasing distance from the fault. It is speculated that this evolution is due to the unlocking of the fault after the earthquake, leading to significant post-seismic deformation in the epicentral and surrounding area. Furthermore, the viscoelastic relaxation of the Wenchuan earthquake is the main cause of loading rate variations in the early post-seismic stage in the northeastern Tibetan Plateau.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
Ashwani Kant Tiwari, Chandrani Singh, Eric Sandvol, Sagarika Mukhopadhyay, Arun Singh, Arun Kumar Gupta
Summary: The 2-D Sn attenuation tomographic model in southeastern Tibet near Namche Barwa reveals high attenuation in the central region, with low attenuation observed in the southern part and some small regions beneath the northern side of the study area. The observed Q(Sn) values indicate significant Sn wave energy dissipation due to structural heterogeneity in the uppermost mantle, possibly resulting from the break-up of the subducting Indian Plate.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
Ashwani Kant Tiwari, Chandrani Singh, Eric Sandvol, Sagarika Mukhopadhyay, Arun Singh, Arun Kumar Gupta
Summary: A 2-D Sn attenuation tomographic model was developed to study the shear wave Q values in the uppermost mantle beneath southeastern Tibet. The model revealed significant attenuation variations in the region, possibly due to structural heterogeneity in the mantle.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geochemistry & Geophysics
Cin-Ty Lee, Emily J. Chin
Summary: The formation of cratons during the mid-Archean to mid-Proterozoic period was favored, resulting in stable crustal shields with thick and cold mantle roots. These cratons have remained stable over time due to the high viscosity of the cratonic mantle, possibly influenced by dehydration during the formation process. Grain size may play a more significant role in controlling cratonic strength than the hydrogen content. The cratonic mantle, despite being wet and metasomatized, has achieved strength through the coarsening of grains and the passage of fluids.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geochemistry & Geophysics
T. J. Craig, J. A. Jackson
Summary: Studying the depth distribution of earthquakes in the East African Rift System reveals a correlation between seismic activity depths and the composition and hydration levels of the crust, providing insights into the controlling factors of seismic events.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geochemistry & Geophysics
Mario D'Acquisto, Taco Broerse, Celine P. Marsman, Rob Govers
Summary: We analyzed the results of GNSS measurements with sub-meter accuracy in South America, Southeast Asia, and northern Japan to understand the deformation of overriding plates during megathrust earthquakes. Our findings show that interseismic velocities decrease with distance from the trench, reaching a hurdle where the gradient becomes lower and velocities are small. These hurdles are located 500-1000 km away from the trench and are associated with significant coseismic displacements during major earthquakes. Finite element models of the earthquake cycle suggest that the hurdles result from a contrast in the mechanical properties of the overriding plate, with a stiffer plate beyond the hurdler. Previous studies have found major tectonic or geological boundaries near these observed hurdles, indicating their significance.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Multidisciplinary Sciences
G. Barcheck, E. E. Brodsky, P. M. Fulton, M. A. King, M. R. Siegfried, S. Tulaczyk
Summary: Research shows that migratory nucleation is more prevalent than self-nucleation in the earthquake cycle of the Whillans Ice Plain.
Article
Geochemistry & Geophysics
Halfdan Pascal Kierulf, Holger Steffen, Valentina R. Barletta, Martin Lidberg, Jan Johansson, Oddgeir Kristiansen, Lev Tarasov
Summary: In Fennoscandia, ongoing crustal deformation is caused by tectonics, Glacial Isostatic Adjustment (GIA), and climatic changes, with a velocity field provided by the BIFROST project. The vertical deformation rates can be used for removal of contributions to analyze residual uplift signals, indicating potential improvements of GIA model or regional tectonic processes. The velocity field shows uplift in northern Sweden and subsidence in northern Central Europe, with plate motion dominating the horizontal velocity field.
JOURNAL OF GEODYNAMICS
(2021)
Article
Geochemistry & Geophysics
Bogdan Matviichuk, Matt A. King, Christopher S. Watson, Machiel S. Bos
Summary: The study uses GPS observations of ocean tide loading displacements to infer the anelastic properties of the asthenosphere, finding strong spatial coherence of M-2 residuals across the North Island of New Zealand. The best fit model combines tide model, spatially variable ocean density and water compressibility, and Earth model, suggesting the need to consider the region's rheological structure to explain the observations.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Oceanography
Mohammad-Hadi Rezvani, Christopher S. Watson, Matt A. King
Summary: This study explores the relationship between absolute sea-level measured by a satellite altimeter and relative sea-level measured by tide gauge, developing a Kalman filtering and smoothing framework to estimate VLM and systematic errors in a geocentric reference frame. Evaluation in the Baltic Sea showed improved agreement between ALT and TG records, leading to a reduction in sea-level rise rate.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Geosciences, Multidisciplinary
Matt A. King, Christopher S. Watson, Duanne White
Summary: This study investigates the vertical motion of bedrock in the Totten-Denman glacier region of East Antarctica using new GPS timeseries. The analysis suggests that surface mass balance loading is the dominant factor contributing to random-walk-like noise in GPS data. After correcting for various factors, subsidence is observed in all sites except for the Totten Glacier region.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Nahidul Hoque Samrat, Matt A. King, Christopher Watson, Andrea Hay, Valentina R. Barletta, Andrea Bordoni
Summary: Through GPS observations and digital elevation models, the study demonstrates that the rheology and ice-mass change in the northern Marguerite Bay region of the Antarctic Peninsula are influenced by viscoelasticity, and the non-linear uplift phenomenon can be explained by a layered viscoelastic model.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Achraf Koulali, Pippa L. Whitehouse, Peter J. Clarke, Michiel R. van den Broeke, Grace A. Nield, Matt A. King, Michael J. Bentley, Bert Wouters, Terry Wilson
Summary: This study investigates the response of the solid Earth to surface mass balance (SMB) variations in the Southern Antarctic Peninsula (SAP) using GPS vertical time series. The results show that interannual SMB anomalies cause measurable elastic deformation, indicating the importance of considering SMB variability in understanding the glacial isostatic adjustment signal in Antarctica.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Review
Multidisciplinary Sciences
Chris R. Stokes, Nerilie J. Abram, Michael J. Bentley, Tamsin L. Edwards, Matthew H. England, Annie Foppert, Stewart S. R. Jamieson, Richard S. Jones, Matt A. King, Jan T. M. Lenaerts, Brooke Medley, Bertie W. J. Miles, Guy J. G. Paxman, Catherine Ritz, Tina van de Flierdt, Pippa L. Whitehouse
Summary: The East Antarctic Ice Sheet, which contains the majority of Earth's glacier ice, is considered less vulnerable to global warming compared to other ice sheets. However, recent mass loss in certain regions has prompted a re-evaluation of its sensitivity to climate change. While some marine-based catchments are currently losing mass, projections indicate increased accumulation in the East Antarctic Ice Sheet over the next century, maintaining overall balance. However, under high-emissions scenarios beyond 2100, significant ice discharge and sea-level rise could occur unless the Paris Agreement goals are met.
Article
Geochemistry & Geophysics
Mohammad-Hadi Rezvani, Christopher S. S. Watson, Matt A. A. King
Summary: The study employed a space-time Kalman approach to investigate vertical land motion and altimeter systematic errors around the Australian coast, revealing new findings such as coastal subsidence, time variability in altimeter errors, and acceleration of ASL rates. The study's approach improves the ability to explore nonlinear localized signals and is suitable for other regional- and global-scale studies.
JOURNAL OF GEODESY
(2022)
Article
Geochemistry & Geophysics
Grace A. Nield, Matt A. King, Achraf Koulali, Nahidul Samrat
Summary: Large earthquakes near Antarctica can cause postseismic deformation that needs to be considered when constraining geophysical models.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Environmental Sciences
Boye Zhou, Christopher Watson, Benoit Legresy, Matt A. King, Jack Beardsley
Summary: In this paper, an improved GNSS buoy approach was proposed for altimetry validation, which was enhanced based on in situ observations. The results showed that the implementation of different ambiguity fixing strategies for various constellations in the processing software TRACK led to a reduction of up to 3 cm in the root mean square of the buoy minus co-located mooring sea surface height residuals. It was also suggested that there might exist a common mode error external to GNSS processing, as indicated by the comparison between double differencing and precise point positioning solutions. The performance of the buoy design under real operating conditions was assessed using GNSS and INS observations, showing no significant relationship under different ocean conditions and sea states.
Article
Geography, Physical
Ole Richter, David E. Gwyther, Matt A. King, Benjamin K. Galton-Fenzi
Summary: This study quantifies the impact of tides on Antarctic ice shelf melting and continental shelf seas using an ocean model. It finds that activating tides increases total basal mass loss and decreases continental shelf temperatures. Tidal currents strongly influence the turbulent exchange of heat and salt, with both dynamical and thermodynamic effects driving the melting process. These findings highlight the importance of incorporating tides into glacier system and shelf sea modeling.
Article
Geosciences, Multidisciplinary
Grace A. Nield, Matt A. King, Rebekka Steffen, Bas Blank
Summary: The finite-element model presented in this study, built in the software package Abaqus, is a global and spherical model designed to calculate post-seismic deformation in the far field of major earthquakes. The model includes linear Maxwell and biviscous rheological models, can be easily adapted to different lateral variations in Earth structure, and has been benchmarked against existing models for various fault geometries with good agreement. Due to the inclusion of self-gravity, the model has the potential to predict deformation in response to multiple sources of stress change.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2022)
Article
Geosciences, Multidisciplinary
Martin Horwath, Benjamin D. Gutknecht, Anny Cazenave, Hindumathi Kulaiappan Palanisamy, Florence Marti, Ben Marzeion, Frank Paul, Raymond Le Bris, Anna E. Hogg, Ines Otosaka, Andrew Shepherd, Petra Doell, Denise Caceres, Hannes Mueller Schmied, Johnny A. Johannessen, Jan Even Oie Nilsen, Roshin P. Raj, Rene Forsberg, Louise Sandberg Sorensen, Valentina R. Barletta, Sebastian B. Simonsen, Per Knudsen, Ole Baltazar Andersen, Heidi Ranndal, Stine K. Rose, Christopher J. Merchant, Claire R. Macintosh, Karina von Schuckmann, Kristin Novotny, Andreas Groh, Marco Restano, Jerome Benveniste
Summary: Studies on the global sea-level budget and ocean-mass budget are crucial for understanding the reliability of sea-level change and its contributors. In this study, datasets for the sea-level budget and ocean-mass budget were analyzed using a consistent framework of uncertainty characterization. The findings show that the sea-level rise trend aligns with the sum of the mass and steric components.
EARTH SYSTEM SCIENCE DATA
(2022)
Article
Geosciences, Multidisciplinary
Steven J. Phipps, Jason L. Roberts, Matt A. King
Summary: Parameterisations are simplified schemes used in geoscientific models to describe physical processes, with values that may be poorly constrained. Uncertainty in parameter values leads to uncertainty in model outputs. A systematic approach for sampling parameter space is necessary for proper quantification of uncertainty in model predictions. Large ensemble modelling is required to incorporate the uncertainty arising from parameterisation of physical processes.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2021)