A5062954087- earthquake and tectonic studies
- Geophysics and Gravity Measurements
- Earthquake Detection and Analysis
- Ionosphere and magnetosphere dynamics
- GNSS positioning and interference
- Geomagnetism and Paleomagnetism Studies
- Seismic Waves and Analysis
- High-pressure geophysics and materials
- Geological and Geochemical Analysis
- Seismology and Earthquake Studies
- Planetary Science and Exploration
- Geology and Paleoclimatology Research
- Cryospheric studies and observations
- Solar and Space Plasma Dynamics
- Inertial Sensor and Navigation
- Geological and Geophysical Studies
- Methane Hydrates and Related Phenomena
- Astro and Planetary Science
- Climate variability and models
- Space Science and Extraterrestrial Life
- Meteorological Phenomena and Simulations
- Computational Physics and Python Applications
- Oceanographic and Atmospheric Processes
- Geophysics and Sensor Technology
- Landslides and related hazards
Hokkaido University
2016-2025
Shanghai Astronomical Observatory
2022-2025
Rigaku (Japan)
2024
Chinese Academy of Sciences
2024
Geological Survey of India
2022
Sepuluh Nopember Institute of Technology
2021
Sapporo University
2020
Graduate School USA
2014-2018
Marymount University
2015
National Astronomical Observatory of Japan
1997-2014
[1] The 2011 March 11 Tohoku-Oki earthquake (Mw9.0) caused vast damages to the country. Large events beneath dense observation networks could bring breakthroughs seismology and geodynamics, here I report one such finding. Japanese network of Global Positioning System (GPS) detected clear precursory positive anomaly ionospheric total electron content (TEC) around focal region. It started ∼40 minutes before reached nearly ten percent background TEC. lasted until atmospheric waves arrived at...
We investigate crustal deformation in southwest Japan over a 3‐year period revealed by permanent dense Global Positioning System (GPS) array. Southwest is part of the Amurian Plate, microplate moving about 10 mm/yr toward east with respect to Eurasian Plate. It overrides Philippine Sea Plate at Nankai Trough and collides northeast arc central Japan. In this paper we first derive GPS site velocities relative stable order isolate signals caused subduction and/or collision. The velocity field...
Using GPS total electron content (TEC) measurements, we analyzed ionosphere response to the great Kurile earthquake of 4 October 1994. High spatial resolution Japanese dense array receivers (GEONET) provided us unique opportunity observe evolution coseismic ionospheric disturbances (CID), which propagated for more than 1800 km away from epicenter. Plotting a traveltime diagram CID and using an “array processing” technique within approximation spherical wavefront, observed phenomenon...
The massive Tohoku-Oki earthquake of a moment magnitude (M w ) 9.0 occurred on 11 March, 2011 off the Pacific coast Northeastern Japan.The mass redistribution in and around focal region associated with this was studied using gravity changes detected by Gravity Recovery Climate Experiment (GRACE) satellite.After 2004 Sumatra-Andaman 2010 Central Chile (Maule) earthquakes, present study presents third case clear detection coseismic GRACE.The observed were dominated decrease over back-arc ∼7...
We studied ionospheric responses to the 2012 April 11 Mw 8.6 North Sumatra earthquake using total electron content (TEC) measurements with regional Global Navigation Satellite System network. This ruptured oceanic lithosphere off Indian Ocean coast of Sumatra, and is known as largest strike-slip ever recorded. Coseismic disturbances (CIDs) rapid TEC enhancement a few units propagated northward speed acoustic waves (∼1 km s–1). Resonant atmospheric oscillation frequency ∼4 mHz have been found...
Research Article| June 13, 2018 Development of a Slow Earthquake Database Masayuki Kano; Kano aEarthquake Institute, The University Tokyo, 1‐1‐1 Yayoi, Bunkyo‐ku, Tokyo 113‐0032, Japan, babasatoru@eri.u-tokyo.ac.jp, kano@eri.u-tokyo.ac.jp, obara@eri.u-tokyo.ac.jp, maeda@eri.u-tokyo.ac.jp, akiko-t@eri.u-tokyo.ac.jpqNow at Department Geophysics, Graduate School Science, Tohoku University, 6‐3 Aramaki Aza‐Aoba, Aoba‐ku, Sendai, Miyagi 980‐8578, Japan; masayuki.kano.a3@tohoku.ac.jp. Search for...
Abstract The global mean sea level (GMSL) was reported to have dropped 5 mm due the 2010/2011 La Niña and recovered in 1 year. With longer observations, it is shown that GMSL went further up a total amount of 11.6 by end 2012, excluding 3.0 mm/yr background trend. A reconciled budget, based on observations Argo project, altimeter, gravity satellites, reveals true rise has been masked El Niño–Southern Oscillation‐related fluctuations its rate increased since 2010. After extracting influence...
Abstract A large eruption occurred on Jan. 15, 2022, at the submarine volcano Hunga Tonga-Hunga Ha’apai, southern Pacific, and atmospheric Lamb wave was observed to have traveled round Earth multiple times with a speed of ~ 0.3 km/s. Here, I compare their ionospheric signatures using data from dense arrays barometers GNSS stations in Japan. confirmed that disturbances passed over Japan least four times, first SE NW, then NW SE, again finally SE. The propagation velocity as fast wave,...
We use Global Positioning System (GPS) velocity data to model eastern Asian plate kinematics. Out of 15 stations in Korea, Russia, China, and Japan studied here, three sites considered be on the stable interior hypothetical Amurian Plate showed eastward velocities as fast ∼9–10 mm/yr with respect Eurasian Plate. They were stationary relative each other within 1 mm/yr, these vectors together those a few additional used accurately determine instantaneous angular (Euler) vector The predicted...
Surveys by continuous Global Positioning System in and around Japan revealed that the Amurian Plate collides with North American central ∼2 cm/yr. Long‐term crustal deformation seems to be influenced mainly this collision although subduction of oceanic plates governs short‐term elastic over arc. Here we study long‐term field carefully removing signals inferred from a‐priori plate convergence vectors coupling strengths predicted a thermal model. The obtained shows change velocities occurs...
Near‐field coseismic perturbations of ionospheric total electron content (TEC), caused by direct acoustic waves from focal regions, can be observed with Global Positioning System (GPS). They appear 10–15 min after the earthquake typical periods ∼4–5 and propagate as fast ∼1 km/s toward directions allowed ambient geomagnetic fields. Ionospheric disturbance, associated 2004 December 26 great Sumatra‐Andaman earthquake, was recorded nine continuous GPS receiving stations in Indonesia Thailand....
Distinct periodic variations with annual frequencies are often found in the time series of continuous Global Positioning System (GPS) site coordinates northeastern Japan. They show maximum arc-normal contraction a few millimeters as well subsidence 1 to 2 centimeters, both March. In Japan, it snows heavily on western flank backbone range, attaining depth several meters When observed snow depths were compared load distribution estimated from GPS data, surface loads caused by be largely...
The Japanese dense array of Global Positioning System recorded ionospheric disturbances as changes in Total Electron Content ∼12 minutes after the September 1 2004 eruption Asama Volcano, Central Japan. disturbance had a period one and quarter propagated fast ∼1.1 km/s, suggesting its origin acoustic wave generated by explosion. By comparing amplitudes with those surface mine blast known energy, overall explosion energy is inferred to be about 2 × 10 14 J.
The first map of coseismic changes in gravity and geoid height has been drawn using the data from Gravity Recovery Climate Experiment (GRACE) satellites for 2004 Sumatra‐Andaman earthquake. Here we present second case change observation by satellite gravimetry, i.e., caused an interplate thrust earthquake that occurred on 27 February, 2010 Central Chile ( M w = 8.8). showed a negative jump with largest drop ∼5 μ gal back‐arc side. observed agree those calculated assuming realistic earth...
Abstract Using Total Electron Content (TEC) measurements with Global Positioning System we studied ionospheric responses to three large earthquakes that occurred in the Kuril Arc on 04 October 1994, 15 November 2006, and 13 January 2007. These have different focal mechanisms, i.e. high-angle reverse, low-angle normal faulting, respectively. TEC 2006 2007 events initiated positive negative changes, On other hand, initial changes 1994 earthquake showed both polarities depending azimuth around...
Abstract Possible enhancement of ionospheric Total Electron Content (TEC) immediately before the 2011 Tohoku‐oki earthquake (M w 9.0) has been reported by Heki (2011). Critical responses to it often come in two stages; they first doubt itself and attribute an artifact. Second (when accept enhancement), significance among natural variability space weather origin. For example, Kamogawa Kakinami (2013) attributed artifact falsely detected combined effect highly variable TEC under active...
Abstract Ionospheric electron enhancement was reported to have occurred ~40 min before the 2011 Tohoku‐oki ( M w 9.0) earthquake, Japan, by observing total content (TEC) with Global Navigation Satellite Systems receivers. Their reality has been repeatedly questioned due mainly ambiguity in derivation of reference TEC curves from which anomalies are defined. Here we propose a numerical approach, based on Akaike's information criterion, detect positive breaks (sudden increase rate) vertical...
We studied ionospheric disturbances associated with the two large earthquakes in Sumatra, Indonesia, namely, 2007 Bengkulu and 2005 Nias earthquakes, by measuring total electron contents (TEC) using a regional network of global positioning system (GPS) receivers. first focus on coseismic (CIDs) earthquake ( M w 8.5). They appeared 11–16 min after propagated northward as fast ~0.7 km/s, consistent sound speed at F layer height. Resonant oscillation TEC frequency ~5 mHz continued for least 30...
On 15 January 2022, a VEI 5 eruption occurred at the submarine Hunga Tonga-Hunga Ha’apai (HTHH) Volcano in Southwest Pacific, causing an ash plume reaching height of 50–55 km. The generated strong acoustic-gravity waves near-field and stations all over world recorded Lamb (LW) that travelled around earth multiple times speed ~0.3 km/s. Here we report ionospheric anomalies due to LW Indonesian islands, 5000–10,000 km away from volcano, terms changes total electron contents (TEC) using...