Anomalous variations in ionospheric TEC prior to the 2011 Japan Ms9.0 earthquake

The ionospheric total-electron-content （IGS） network and the VTEC data from the GPS （TEC） data provided by the International GNSS Service reference stations of Crustal Movement Observational Network of China（CMONC） were processed and statistically analyzed to search for earthquake-related TEC anomalies prior to the 2011 magnitude 9.0 earthquake in Japan. Preliminary results showed that anomalous variations oc- curred 6 - 11 days and 0 - 4 days prior to the earthquake. After considering solar activity, geomagnetic condi- tions, and proximity in space and time to the earthquake, we tentatively concluded that the anomalous increase on March 5 may be related to the earthquake.

Deformation caused by the 2011 eastern Japan great earthquake monitored using the GPS single-epoch precise point positioning technique

Crustal deformation can provide constraints for studying earthquake rupture and shock wave transmission for the Mw9.0 eastern Japan great earthquake. Using the single- epoch precise point positioning （PPP） method and the appropriate positioning flow, we process GPS data from six IGS （International GNSS Service） sites （e.g., MIZU, TSK2, USUD, MTKA, AIRA and KSMV） located in Japan and obtain the positioning results with centimeter scale precision. The displacement time series of the six sites are analyzed using the least squares spectral analysis method to estimate deformations caused by the Mw9.0 mainshock and the Mw7.9 aftershock, and the cumulative displacements after 1 day. Mainshock displacements at station MIZU, the nearest site to the mainshock in the North （N）, East （E）, and Up （U） directions, are -1.202 m, 2.180 m and -0.104 m, respectively, and the cumulative deformations after 1 day are -1.117 m, 2.071 m and -0.072 m, respectively. The displacements at station KSMV, the nearest site to the Mw7.9 aftershock in the N, E and U directions, are -0.032 m, 0.742 m and -0.345 m, respectively. The other sites obviously experienced eastern movements and subsidence. The deformation vectors indicate that the horizontal displacements caused by the earthquake point to the epicenter and rupture. Elastic bounds evidently took place at all sites. The results indicate that the crustal movements and earthquake were part of a megathrust caused by the Pacific Plate sinking under the North American Plate to the northeast of Japan island arc.

Far-field crustal movements before and after the 2011 Ms9.0 Japan earthquake from GPS observations

The paper gives an analysis of the displacement time series before and after the March 11,2011 Ms9.0 east Japan earthquake and co-seismic displacements observed at continuous GPS stations in and around China. The results showed a broad-scaled related elastic-rebound process and some premonitory horizontal crustal movements to this earthquake over this vast area.

Pre-seismic and Co-seismic Crustal Movements of the M 7.3 Kyushu Earthquake on April 16,2016 in Japan

The time series of coordinates of a large number of GPS stations in the world,processed by Prof. Geoffrey Blewitt with GIPSY software are available at http://geodesy. unr. edu.Based on the time series of coordinates in the global reference frame of IGS08 at more than250 stations of continuous GPS observations,downloaded from the website,the co-seismic displacements of the M7. 3 Kyushu earthquake on April 16,2016 in Japan and the preseismic strain accumulations and displacements in the regional reference frame were obtained. The station of continuous GPS observation at BJFS near Beijing has been quite stable in displacement in the eastern part of China for more than 17 years since the beginning of its operation,and this station is used as the core station in the regional reference frame for the pre-seismic displacement of the Kyushu earthquake of M7. 3. The main feature of the pre-seismic displacements of the Kyushu earthquake is characterized by locking in the crust at and near the epicenter. The anomalous pre-seismic strain accumulation developed in an area of anomalous accumulation of the shear strain component of γ1 on the northeast side of the epicenter,with increasing size of the area and increasing magnitude in γ1. The largest area covered by the anomalous γ1 is about 2000 km2. The change in the E component at BJFS since November 26,2015 was caused by the replacement of the receiver and the antenna at the station. In order to study the shortterm change in displacements at stations at and near the epicenter,the time series at 3 stations with continuous GPS observations,2 at SUWN and DAEJ in south Korea and 1 at BJSH near Beijing were analyzed. The analysis shows that the displacements at the 3 stations have been quite stable in the same manner in east Asia. Thus,BJSH is used as the core station in the regional reference frame of displacement and the displacement time series show that there were no significant short term anomalies before the earthquake.

Temporal variation of gravity-field in North China before and after the 2011 Japan Mw9. 0 earthquake

By using absolute and relative-gravity data recorded by the gravity network in North China, we obtained some large-scale and high-spatial-resolution images of gravity variation in this area for the first time. By analyzing these images, we found that the gravity in Liaodong peninsula area showed an obvious increase of 80 × 10^-8ms^-2 during about one- and-half year before the 2011 Japan Mwg. 0 earthquake, and a rapid decrease after the earthquake. This gravity variation is similar to that observed previously for the 1976 Tangshan 1147.8 earthquake.

Co-seismic deformation of 2011 Mw9.0 Japan earthquake observed by InSAR technique

Co-seismic line-of-sight displacements of the 2011 Mw9.0 Japan earthquake derived from InSAR data of Envisat ASAR, ALOS PALSAR and TerraSAR-X show a maximum value of about - 245cm to -221cm near the epicenter. This result is in good agreement with the result of GPS measurement. The ob- served displacement pattern suggests an earthquake-rupture zone over 500km long, with a ground-motion pat- tern in the vicinity of the northern segment more complex than that of the southern segment, possibly due to immediate aftershocks that occurred between satellite passes.

Influence of the 2011 Mw9. 0 Japan earthquake on groundwater levels in Chinese mainland

This paper gives a description of the co-seismic and post-seismic groundwater level changes induced in Chinese mainland by the 2011 Mw9.0 Japan earthquake, and the corresponding stress changes calculated on the assumption of linear elasticity. The result shows that the main types of changes were oscillations and step increases. The North-South Seismic Belt and the Shanxi Seismic Belt were the main areas affected by the earthquake.

Response of tilt and strain meters in Hubei province to the 2011 Mw9. 0 Japan earthquake

Tih and strain meters of the deformation-observation network in Hubei Province all responded to the Mw9.0 Japan earthquake on March 11,2011. By analyzing the co-seismic responses,we found that firstly there was essentially a linear correlation between response time and epicentral distance. Secondly, there was some correlation between maximum response amplitude and earthquake magnitude as well as between the duration and earthquake magnitude. Thirdly, the response amplitudes and decay rates were different for different types of instruments. Due to less data-sampling frequency, the deformation instruments, could not display the first motion of P and S waves, but responded mainly to far-field surface waves. Before the earthquake, the NS earthtide component recorded by the cave stainmeter at Yichang was distorted for nearly eight hours. While digital deformation observation did not show complete information about the earthquake source, it still reflected some key features of seismic-wave propagation.

Strain Energy Release from the 2011 9.0 Mw Tōhoku Earthquake, Japan

The purpose of this paper is to compare the strain energy released due to elastic rebound of the crust from the tragic 2011 9.0 MwTōhoku earthquake in Japan with the observed radiated seismic energy. The strain energy was calculated by analyzing coseismic displacements of 1024 GPS stations of the Japanese GEONET network. The value of energy released from the analysis is 1.75 × 1017J, which is of the same order of magnitude as the USGS-observed radiated seismic energy of 1.9 × 1017Nm (J). The strain energy method is independent of seismic methods for determining the energy released during a large earthquake. The analysis shows that although the energy release is concentrated in the epicentral region, about 12% of the total energy was released throughout the Japanese islands at distances greater than 500 km west of the epicenter. Our results also show that outside the epicentral region, the strainenergy was concentrated along known tectonic zones throughout Japan.

Analysis of Ship Refuge Action in Tsunami Using AIS Data： Case of the 2011 East Japan Earthquake and Tsunami

A massive earthquake occurred in the Tohoku and Kanto regions of Japan on the 1 lth of March 2011. In response, a tsunami alert, a tsunami warning and an advisory were issued for the entire Pacific coast region. This research investigates the evacuation behavior of ships by AIS （automatic identification system） data in Onahama port after the tsunami warning was issued. The unusual behavior observed was attributed to the emergency evacuation of ships. This research investigates the evacuation behaviors of the vessels using the data obtained from AIS, around the Onahama Port during alerting the major tsunami warning. The result shows that most vessels in the port started evacuating approximately 10 min after the major tsunami warning and completed offshore evacuation 40 min after this warning. This contributed in understanding the actual status of the vessel evacuation. In addition, the travel paths of each vessel revealed the influence of the tsunami on the vessels. Furthermore, the exceptional situation where several vessels moved in the same direction at the speed almost same for about 2 hours was confirmed. As a result, it can be estimated that the waves that affected both vessels were the drawback of the tsunamis.

Evaluation of the Long-Term Changes in Fatigue of Cancer Survivors Who Received Outpatient Chemotherapy in the Area Affected by the Great East Japan Earthquake

Objective: The aim of the study is to evaluate the long-term changes in fatigue of cancer patients receiving outpatient chemotherapy after a disaster such as the Great Earthquake. Methods: From 2012 to 2014, we measured subjective fatigue, autonomic function, and physical activity with reference to the criteria for chronic fatigue syndrome. Results: The participants were 13, 9 males (69.2%) and 4 females (30.8%). The most common cancer among the participants was lung cancer 4 patients (30.8%). In 2012, eight patients (61.6%) received anti-cancer drugs and three (23.0%) received the drug by intravenous drip and oral administration. Physical fatigue (p = 0.004), mental fatigue (p = 0.002), comprehensive fatigue (p = 0.012), and comprehensive evaluations (p = 0.032) were significantly different. Significant differences in the autonomic nervous function were observed during the three years from 2012 to 2014 (log LF [p = 0.017], log HF [p = 0.023] and log LF/HF [p = 0.039]). Similar to Subjective fatigue, Significant differences in physical activity were observed during the three years from 2012 to 2014 (DA [p = 0.042], TST [p = 0.037], SE [p = 0.018], AW [p = 0.023] and Naps [p = 0.014]). Conclusions: The participants fatigue worsened at one time, but showed improvement over time. In the event of an emergency such as a disaster, it is necessary to evaluate the physical and mental condition based on objective indicators of cancer patients receiving anti-cancer drug treatment and provide nursing support.

GIS as an Information Infrastructure for Recovery and Reconstruction after the Great East Japan Earthquake

This study considers the regional characteristics of the Tohoku region and the extent of the damage caused by the Great East Japan Earthquake and makes proposals for recovery and reconstruction of the areas affected by this disaster as well as for a reduction of the impact of natural disasters that may occur in the future with GIS （geographic information systems） as a social infrastructure positioned at the heart of the information infrastructure. Due to the fact that social media that used ICT （information and communication technology） was useful in the days directly after the disaster, it can be said that it is necessary to investigate the provision of an information infrastructure that uses ICT to reduce the impact of disasters. Therefore, this study proposes the construction of a geographical information database using GIS and the provision and sharing of information using social media GIS after discussion of the relationship between the development of the computerization of Japan and GIS as a valid example of using information systems for recovery and reconstruction after the Great East Japan Earthquake.

Damage of 1975 Haicheng M_s7.3 earthquake in the Korean Peninsula and its effect on Kyushu,Japan

The 1975 Haicheng Ms7.3 earthquake affected whole Korean Peninsula and even Kyushu, Japan. In this paper isoseismal map of this earthquake was drawn for these areas by sorting out and analyzing data systematically collected, furthermore, the characteristics of the earthquake damage were discussed. In the northern Korean Peninsula, the intensity is V in great majority of this area except local area with intensity VI, and the damage is basically in accordance with typical characteristics of corresponding intensity grade. In the southern Korean Peninsula, the intensity is IV in large part of the area, however, in some big cities such as Seoul etc., not only high buildings shook strongly, but also some people appeared perceptions such as feeling dizzy and so on, and electrical service was interrupted on one or two districts because of transformer tripping. These phenomena could be caused by the effect of long-period wave generated from a large earthquake on far-field.

Co-seismic groundwater-level and temperature changes of the 2011 Mw9. 0 Japan earthquake in Chinese mainland

Co-seismic groundwater-level and temperature changes caused by the Mw9. 0 Japan earthquake in Chinese mainland are described. The recorded water-level changes were mostly oscillations, with some step decreases mostly in the coastal area of Southeast China and step increases mostly in Northeast China and the North-South Seismic Belt. The water-temperature changes were mainly decrease with slow recovery in Sichuan- Yunnan, South China, and lower reaches of Jiangzhong, and sharp increase followed by sharp decrease, or vice versa, in North China and Northeast China. For wells that showed step changes in both water level and temperature, more showed them in the same direction than in the opposite direction.

Seismic Design of Offshore Wind Turbine Withstands Great East Japan Earthquake and Tsunami

Japan＇s first open sea offshore wind farm, Kamisu offshore windfarm Phase l, was stricken by an earthquake of intensity 6 on the Japanese seismic scale and a five-meter-high tsunami during the Great East Japan Earthquake on March 11,2011. The wind farm resumed operation on March 14 after checks revealed no damage to the system, even though the wind farm was temporarily forced to stop due to the grid failure caused by the earthquake. Wind turbines require a precise seismic design especially in an earthquake-prone country such as Japan. Wind power Kamisu Phase 2 was built one year after the earthquake based on the experience of Kamisu Phase 1. This paper presents the seismic design of offshore wind turbines and the situation during the earthquake and tsunami.

New energy policy and low-carbon society in Japan after the Great East Japan Earthquake

The Great East Japan Earthquake in March 2011 devastated the eastern region of Japan.Due to the resulting nuclear accident,Japanese Cabinet decided to revise its energy policies.The Energy and Environment Council in National Policy Unit published options on the nation's scenarios for energy and economy in 2030.We estimated the economic impacts of the options to national economy and households in 2030.Finally,we clarified significant factors to establish a secure,affluent and low-carbon society based on the energy scenarios.

Characteristics of earthquake clustering in and around Japan revealed by single-link cluster analysis

In this study,we apply the single-link cluster(SLC)method to analyze the characteristics of earth-quake clustering in Japan.Among the clustering algorithms,the SLC method is effpctive in characterizing earthquake clusters or isolated events at both global and local scales.The results indicate that link lengths for the whole investigated area in and around Japan follow negative exponential functi-onal or Gamma distribution functional increase.Besides,some difference is revealed among different areas,e.g.,link lengths in the area of the Japan Trench and the Kuril Trench are shorter than those in other areas;the densest spatial distribution of the SLC framework is also in the area of the Japan Trench and the Kuril Trench.The close investigations indicate that the a and 1/θvalues estimated respectively from the exponential function and Gamma distribution may relate to spatial clustering,which is supported by the results of the distribution of link lengths and the spatial distribution of the SLC framework in the investigated areas.

Digitization characteristics of geothermal information and structural analysis of 2011 off the Pacific coast of Tohoku Ms9.0 earthquake

Earthquake is one of the difficult problems that can not be solved as of this writing since the time when mod- em science was initiated over 300 years ago, and irregular events cannot be dealt with by using quantities examples before and followed by a view of the number of analysis systems in modem science ; meanwhile, it covers the problem that how to use changeable information. Structural analysis method is developed particularly for the study of evolutionary transitional processes of the changing events by employing irregular information, and emphasizes the primitiveness of changes in events. Based on the data of sounding observation every 08 o＇ clock and 20 o＇ clock per day from China Meteorological Administration, in this paper, we employ the digital structural analysis method to analyze the process of the special, structural characteristics of 2011 off the Pacific coast of Tohoku Ms9.0 earthquake. The result shows that the method can reflect the process of geothermal structures before and after earthquake; it can reflect the congruity between geothermal ＂heat level＂ and the level of earthquake energy. When the structure before the earthquake is ＂the counter clockwise rolling current and the unstable structures＂ with ＂dry in lower levels and wet in upper levels＂, we should be worry about the problem of earthquake. In a word, geothermal information could reveal that earthquakes really would be ＂heralded＂.

Characteristics of Tsunami Damage to the Tide Walls in Iwate Prefecture from the Great East Japan Earthquake

This research paper describes the tsunami damage to tide walls observed using aerial photographs and field investigations at 13 locations along the coast of Iwate Prefecture, where significant tsunami damage occurred as a result of the Great East Japan Earthquake. This paper also summarizes the characteristics of the damage. The tide walls in Iwate Prefecture were constructed on a ria （hilly type） coast, this geographical feature of lwate being different from that of the other disaster areas, primarily Miyagi and Fukushima Prefectures. The results of our investigations show that all the devastated tide walls suffered from overflow before being damaged. In particular, the sloping and vertical type tide walls with slope protection were damaged by scouring of the infill sand or back fill soil due to the overflow of the tsunami. In the case of vertical type tide walls without slope protection, damage was caused by scouring of the back fill soil.

Responses of the East Component of Beijing GNSS Continuous Observation Stations to the 2011 Japan M_W 9.0 Earthquake

Several new demands have been put forward for the application of the Beijing continuous GNSS observations due to some particular reasons, such as the limited coverage of the observation network, the different construction and management criterion executed by different units and the intense interference resulting from human activity. In this paper, necessary processing of data is carried out, including more accurate calculation, corrections to the replacement, outliers and relocation of equipment, and elimination of linear trends in the E-component for every station. The E-components of the 16 available stations showed a lower sawtooth wave anomaly （slowly westward propagating） before the 2011 Tohoku Mw9. 0 earthquake, a coseismic step rebound （rapid eastward propagating） and a post-seismic D-shaped recovery. These steps constituted a complete earthquake process which was rarely seen before in the GNSS observations and provides a good example for further study. Moreover, the rapid eastward propagating during the earthquake is not influenced by the size of the given normal values, which may play a significant role in earthquake forecasting and early warning.