Article
Geosciences, Multidisciplinary
Sambuddha Dhar, Jun Muto
Summary: We propose a new function model that incorporates laboratory-derived constitutive laws in mechanical postseismic models. This model accurately predicts the decade-long time series of inland GNSS stations and decomposes them into displacements due to viscoelastic relaxation and afterslip. It provides insights into various deformation mechanisms and is an effective tool for forecasting long-term GNSS time series.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Review
Geochemistry & Geophysics
N. Uchida, R. Burgmann
Summary: Research has shown that there were indications of a potential great megathrust earthquake in NE Japan before the 2011 Tohoku earthquake, but a consensus assessment of the hazard was lacking. Since the earthquake, studies have made significant progress in revealing aspects such as coseismic rupture, aftershocks, and slow earthquakes.
REVIEWS OF GEOPHYSICS
(2021)
Article
Geochemistry & Geophysics
Junichi Fukuda, Kaj M. Johnson
Summary: A method for estimating the parameters of postseismic deformation models following great subduction earthquakes was developed, incorporating afterslip and viscoelastic relaxation mechanisms. Bayesian formulation and algorithm were used to estimate the posterior probability density function, allowing for quantification of uncertainties in the model parameters. Application to the 2011 Tohoku-Oki earthquake showed tight constraints on the model parameters, effectively reproducing spatial and temporal patterns of postseismic deformation.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Review
Geosciences, Multidisciplinary
Sambuddha Dhar, Jun Muto, Yusaku Ohta, Takeshi Iinuma
Summary: The 2011 Tohoku-oki earthquake provided valuable data for studying postseismic deformation and the rheological heterogeneities of the viscoelastic earth. Researchers used a dense network of GNSS stations to investigate the different mechanisms responsible for the observed crustal deformation. However, the contribution of rheological heterogeneities to postseismic deformation is still poorly understood.
PROGRESS IN EARTH AND PLANETARY SCIENCE
(2023)
Article
Engineering, Aerospace
Keke Xu, Rong He, Kezhao Li, Ankang Ren, Zhenhua Shao
Summary: By focusing on high-precision GNSS data processing and analysis, the study reveals the dynamic evolution of tectonics and crustal deformation along subduction zones. Common Mode Errors are removed, deformation signals are extracted, and regional spatiotemporal filtering is utilized to comprehensively display crustal motion characteristics.
ADVANCES IN SPACE RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Satoshi Fujiwara, Mikio Tobita, Shinzaburo Ozawa
Summary: Postseismic deformations continue for a long period after major earthquakes and can be approximated using simple functions. Statistical data processing on postseismic deformations due to the 2011 Tohoku-Oki earthquake revealed their spatiotemporal distribution. A combined functional model of three functions was used to approximate the postseismic deformations over a wide area for approximately 10 years, but the residuals from the model deviated significantly since 2015.
EARTH PLANETS AND SPACE
(2022)
Article
Geosciences, Multidisciplinary
Liming He, Lixin Wu, Kosuke Heki, Cong Guo
Summary: This study presents the anomalities of total electron content in the ionosphere before the 2011 M(w)9.0 Tohoku-oki earthquake, observed in northern Australia by the Global Navigation Satellite System (GNSS) stations. The onset time of the anomaly, determined by the Akaike's information criterion, is very close to the time observed in Japan. The positive TEC anomalies in Australia appear on the same longitude as the land area of NE Japan, supporting the model that electric fields within the ionosphere redistribute the electrons before large earthquakes.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geochemistry & Geophysics
Isabelle Panet, Clement Narteau, Jean-Michel Lemoine, Sylvain Bonvalot, Dominique Remy
Summary: In this study, we conducted a global analysis of GRACE-reconstructed gravity gradients to investigate the existence of deep signals preceding the Tohoku earthquake in 2011. Our findings demonstrate the presence of a unique solid Earth signal, which is independent of oceanic corrections, and can be utilized for continuous monitoring of the Pacific subduction belt.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Review
Geosciences, Multidisciplinary
Bunichiro Shibazaki
Summary: This paper summarizes 10 years of research on the earthquake cycles and crustal deformation associated with the 2011 Tohoku-oki earthquake. Several models have been proposed to explain the occurrence of megathrust earthquakes and large slips in the northeast Japan subduction zone. The study observed submarine crustal deformation and discussed the effects of the low-viscosity region and the cold nose. Simulations showed that the Tohoku-oki earthquake caused large stress fluctuations and subsidence in the Pacific coastal region.
PROGRESS IN EARTH AND PLANETARY SCIENCE
(2023)
Article
Geosciences, Multidisciplinary
Orlando Alvarez, Mario Gimenez, Andres Folguera
Summary: In the past decade, the three largest and most destructive earthquakes with associated tsunamis occurred. Technological and scientific advancements have allowed for the unprecedented study and modeling of these phenomena. Gravity field models have been used to infer mass displacements associated with these events, yielding good results when compared with other methods. The study of the 2011 Tohoku-Oki earthquake revealed that the maximum slip occurred near a lobe of minimum Tzz and that the rupture was influenced by density structures.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Engineering, Aerospace
Bingquan Han, Chengsheng Yang, Zhenhong Li, Chen Yu, Chaoying Zhao, Qin Zhang
Summary: The coseismic and postseismic deformation caused by the Petermann earthquake in the Northern Territory of Australia have been determined using satellite images. The earthquake ruptured in the NNW direction with a magnitude of Mw 6.06, and the postseismic deformation showed a gradually decaying trend with a maximum displacement of 5.4 cm within 858 days.
ADVANCES IN SPACE RESEARCH
(2022)
Article
Multidisciplinary Sciences
Piero Bellanova, Mike Frenken, Yuichi Nishimura, Jan Schwarzbauer, Klaus Reicherter
Summary: The 2011 Tohoku-oki tsunami caused massive damage along the northern Japanese Aomori coast, with the coastal control area being inundated up to 550 m inland. A previously undocumented woody-organic tsunami deposit was discovered, improving understanding of the documented part of the tsunami inundation and reducing underestimation.
SCIENTIFIC REPORTS
(2021)
Article
Environmental Sciences
Sen Zhu, Yangmao Wen, Xiaodong Gong, Jingbin Liu
Summary: The largest earthquake (Mw 6.4) in northwestern Croatia occurred near the city of Petrinja on December 29, 2020. The study used satellite images to investigate the geometric and kinematic properties of the earthquake and identified the coseismic and early postseismic surface displacements. The postseismic deformation was attributed to a combination of afterslips and aftershocks in the area, and the correlation between Coulomb stress change and the distribution of aftershocks helped identify active faults and estimate seismic hazards in the region.
Article
Geochemistry & Geophysics
Shunying Hong, Mian Liu
Summary: Using InSAR and GPS observations, this study constructed an afterslip model for the Gorkha region over three years after the 2015 earthquake, confirming that afterslip dominated the observed postseismic deformation, releasing energy equivalent to an Mw 7.32 earthquake. The afterslip occurred mostly in the downdip ductile shear zone and was controlled by rheological properties. The updip portion of the Main Frontal Thrust zone remains potentially seismically active, as it was not ruptured by coseismic slip or unlocked by afterslip.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Remote Sensing
Ankang Ren, Keke Xu, Zhenhua Shao, Xinqi Liu, Xiaoyi Wang
Summary: It is found that colored noise in GNSS time series has significant impact on parameter estimation of general linear trajectory models. To overcome this issue, maximum likelihood estimation is used to estimate the colored noise and a nonlinear least square algorithm with colored noise as the stochastic model is employed to calculate timescale parameters. The method is validated through simulation experiments and has shown significant improvements in reducing iteration times and decreasing parameter estimation deviations compared to traditional methods.
Article
Geochemistry & Geophysics
Sirawich Pipatprathanporn, Frederik J. Simons
Summary: A fleet of autonomously drifting profiling floats known as mermaid monitors seismic activity using hydrophones inside oceans. The floats recorded signals from 213 global earthquakes, with only 10 automatically reported. After removing seismic and other signals, infrasonic ambient noise recorded at 1500 m depth was analyzed, showing interactions of oceanic surface gravity waves.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geosciences, Multidisciplinary
M. Geertsema, B. Menounos, G. Bullard, J. L. Carrivick, J. J. Clague, C. Dai, D. Donati, G. Ekstrom, J. M. Jackson, P. Lynett, M. Pichierri, A. Pon, D. H. Shugar, D. Stead, J. Del Bel Belluz, P. Friele, I Giesbrecht, D. Heathfield, T. Millard, S. Nasonova, A. J. Schaeffer, B. C. Ward, D. Blaney, E. Blaney, C. Brillon, C. Bunn, W. Floyd, B. Higman, K. E. Hughes, W. McInnes, K. Mukherjee, M. A. Sharp
Summary: This article describes and models the recent landslide, tsunami, outburst flood, and sediment plume in the southern Coast Mountains of British Columbia, Canada. The use of physically based models allows for real-time simulations, improving understanding of similar hazard cascades and the associated risks.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Environmental Sciences
Wenhao Li, Fei Li, C. K. Shum, Chanfang Shu, Feng Ming, Shengkai Zhang, Qingchuan Zhang, Wei Chen
Summary: This study uses independent component analysis to remove common mode errors and determine the optimal noise model for GPS data in Antarctica. The results show that all GIA forward models underestimate GPS-observed velocities, and the GPS vertical velocities are larger on the North Antarctic Peninsula compared to the South Antarctic Peninsula.
Article
Geosciences, Multidisciplinary
Young Hong Shin, C. K. Shum, Carla Braitenberg, Sang Mook Lee, Mutaek Lim, Sung-Ho Na, Chunli Dai, Chaoyang Zhang, Yuanjin Pan, Seok-Hyeon Do, Byung-Dal So
Summary: Through the analysis of recent satellite-based gravity models, researchers have discovered the decoupling and folding phenomenon in the Tibetan lithosphere, which has been confirmed by seismic and magnetotelluric explorations. 3D geodynamic simulations have elucidated the buckling structures in the upper crust and lithospheric mantle, leading to a new plausible hypothesis for the growth mechanism of the Tibetan Plateau.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Chunli Dai, Ian M. Howat, Jeffrey T. Freymueller, Zhong Lu, Saurabh Vijay, Anna K. Liljedahl, Melissa K. Ward Jones, Helena Bergstedt, Einat Lev
Summary: Measuring eruption volume is crucial for monitoring volcanoes, and this study used ArcticDEM technology to quantify the recent eruption volumes at Mount Cleveland in Alaska. The results also suggest that the material loss at the volcano's summit crater may be caused by explosions and collapses of the magma chamber, and the elevation changes associated with lahars are highly variable.
JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Stephen Coss, Michael T. T. Durand, C. K. Shum, Yuchan Yi, Xiao Yang, Tamlin Pavelsky, Augusto Getirana, Dai Yamazaki
Summary: River channels play a crucial role in storing large volumes of water globally, affecting ecological and biogeochemical processes. However, there is currently no observational constraint on the quantity of water stored in river channels. This study introduces a 26-year record of remotely sensed volumetric channel water storage (CWS) change on 26 major rivers worldwide, revealing the significant contribution of mainstem CWS climatology amplitude to terrestrial water storage variability in basins.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Yuanjin Pan, Weiping Jiang, Hao Ding, C. K. Shum, Jiashuang Jiao, Jiangtao Li
Summary: The present-day crustal deformation in the Tianshan and Pamir areas is investigated through multi-geodetic observations. Surface hydrology is found to be one of the factors affecting the regional vertical velocity field observed by GPS. The relatively weaker lithosphere beneath the central Tianshan is subject to strong compression, leading to the present-day crustal uplift.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
Xuanyu Hu, C. K. Shum, Michael Bevis
Summary: We propose a new physically motivated triaxial reference ellipsoid for the Earth, which closely approximates the geoid and is an equipotential surface in the gravity field. The ellipsoid is uniquely specified by various factors including the Earth's total mass, dynamic form factors, and rotation rate. We use triaxial ellipsoidal harmonics to model the gravity field and present a practical procedure to iteratively solve for the ellipsoidal parameters.
JOURNAL OF GEODESY
(2023)
Article
Environmental Sciences
Ziyu Shen, Wenbin Shen, Shuangxi Zhang, C. K. Shum, Tengxu Zhang, Lin He, Zhan Cai, Si Xiong, Lingxuan Wang
Summary: The paper presents the SFST approach for connecting local VHSs, which aims to unify the global vertical height datum. This approach utilizes ultraprecise clock frequency signal links between satellites and ground stations to determine geopotential and height differences between ground datum stations. Simulation results show that the VHSs of China and the US can be unified with centimeter-level accuracy, given the stability of atomic clocks. The SFST approach shows promise for achieving IHRS and represents a new paradigm.
Article
Engineering, Civil
Muge Albayrak, Sebastien Guillaume, Daniel Willi, Christian Hirt, Ivan Dario Herrera Pinzon, Urs Marti, M. Tevfik Ozludemir, Lukas Mueller, C. K. Shum
Summary: This study presents the results of an astrogeodetic survey campaign conducted in the mountainous terrain of the Surses region in Switzerland. The observations using the QDaedalus system validated DoV data from the CHGeo2004 model and showed that it is more accurate than the GGMplus model. Furthermore, a comparison with previous studies conducted in coastal and flat terrains revealed that the GGMplus model performs better in the mountainous terrain.
JOURNAL OF SURVEYING ENGINEERING
(2023)
Article
Environmental Sciences
Zhifeng Yu, Jun Zhang, Zheyu Chen, Yuekai Hu, C. K. Shum, Chaofei Ma, Qingjun Song, Xiaohong Yuan, Ben Wang, Bin Zhou
Summary: This study developed a new algorithm based on China's Gaofen imageries to quantify the evolutions and distributions of total suspended particulate matter (TSM) in the Bohai Sea and adjacent regions. The analysis showed that single-band data had weak correlation with TSM, but the correlation was enhanced by combining bands of band ratio calculations. The results indicated spatial variations in TSM within the Bohai Sea, Laizhou Bay, and the Yellow River estuary, with the dynamics of TSM being affected by Yellow River runoff.
Article
Geochemistry & Geophysics
Haijian Liu, Zhifeng Yu, C. K. Shum, Qixia Man, Ben Wang
Summary: This study proposes a hierarchical multiplication (HM) model based on the hierarchical method and stepwise multiplication algorithm for extracting forest coverage using multispectral images. The experiment shows that the combined use of HM and multispectral data can accurately extract forest cover changes and achieve similar results compared to more sophisticated classifications using higher precision/spectral band (hyperspectral) data.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2023)
Article
Geochemistry & Geophysics
Qiang Shen, C. K. Shum, Hansheng Wang, Liming Jiang, Banghui Yang, Chaoyang Zhang, Jinglong Dong, Fan Gao, Weiyu Lai, Tiantian Liu
Summary: A new method is proposed to estimate the measurement biases of glacier elevation products using altimetry crossovers relative to a known stable ice surface. The results show that the measurement biases vary depending on the measurement methods and specific campaigns.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2023)
Article
Engineering, Electrical & Electronic
Qiang Shen, Hansheng Wang, C. K. Shum, Liming Jiang, Banghui Yang, Chaoyang Zhang, Jinlong Dong, Fan Gao, Weiyu Lai, Tiantian Liu
Summary: Based on a study, synthetic aperture radar (SAR) backscatter has a qualitative relationship with soil moisture, suggesting its potential for large-scale high-resolution soil moisture mapping. Researchers proposed a method for directly estimating soil moisture content using the advanced integral equation model and Mironov dielectric model. They generated a time series of high-resolution soil moisture using Envisat ASAR AP data, which showed good agreement with other data products and suitability for watershed-scale hydrological studies.
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
(2023)
Article
Geosciences, Multidisciplinary
Hao Wang, Wenhao Li, Chanfang Shu, C. K. Shum, Fei Li, Shengkai Zhang, Zikang Zhang
Summary: This study explores the performance of different spatiotemporal filtering methods in reducing common mode error (CME) in GNSS networks at different spatial scales and concludes that correlation-weighted spatial filtering (CWSF) is the most effective method.
