地震災害においてはが災害要因の1つとなる．被害予測のためにの物理シミュレーションが試みられており，有限要素法等を用いて詳細な地殻構造を考慮した計算手法が求められている．また地震時のでは不確実性が多数存在しており，計算では入力データに含まれる不確実性を定量的に評価するアプローチが有効である．本研究では多数回計算によるモンテカルロシミュレーションのための，の高速有限要素解析手法を開発した．詳細な有限要素解析に伴う莫大な計算負荷を克服するためにGPUを導入し，適したアルゴリズムの構築により計算を高速化した．琵琶湖西岸断層帯を対象とした適用例では，モンテカルロ法により震源の不確実性を定量的に評価する計算を現実的な時間内で行った．

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噴火に伴う被害の軽減のためには，火山活動のモニタリングが重要である。近年，の空間分布を詳細に把握できる利点から，SARを搭載する「だいち２号」の活用が期待されている。この「だいち２号」の干渉SARにより，箱根山や桜島などで火山活動の活発化に伴うが捉えられた。箱根山では大涌谷でが検出され，継続的な観測により変動の推移が捉えられた。桜島では，捉えられたから昭和火口の直下へのマグマ貫入が推定された。これらの情報は火山噴火予知連絡会などに報告され，評価に活用されている。

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The problem discussed in this paper is whether the crustal movements in the Japanese Islands changed in nature or rate during the transition from the Tertiary to the Quaternary periods. The Late Tertiary sedimentary basins gradually migrated under the control of the orogenic movements which had begun in the Early Miocene. The Lower Pleistocene Series deposited in the areas succeeded the Pliocene sedimentary basins. In most parts of the Japanese Islands, a conspicuous break in sedimentation and physiographic development can be recognized between the Early and Middle Pleistocene. Since the Middle Pleistocene, sediments lap off the underlying sediments and form successive terraces, whereas the younger sediments covered the older during the Early Pleistocene. Flat lying Middle Pleistocene and younger terrace formations are striking in contrast to the folded and faulted Early Pleistocene formations, though the intensity of their deformation varies locally. The break between the Early and Middle Pleistocene mentioned above suggests progressive crustal movements since the Neogene and the relative rise of the whole Japanese Islands against sea level though whether diastrophic or eustatic is not yet certain. Concerning the rate of deformation of the Early and Middle Pleistocene formations, the absolute ages of the sediments must be determined and the mechanism of the deformation be elucidated. In Japan, knowledge on the absolute and relative chronology of the Late Cenozoic is now in progress and the interest of structural geologists with regard to the exact age of the tectonics is increasing. More detailed discussion on dated Quaternary crustal movements will become possible in the near future.

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For the purpose of finding out some clues for the earthquake prediction, continuous observations of crustal deformation with extensometers and tiltmeters at several stations have been carried out during about 20 years. Observational points are Oura, Donzurubo, Amagase and Iwakura, locating almost on a straight line in the SW-NE direction in the central part of the Kinki district. The ground-strains and -tilts were compared with seismic activities in the vicinity of each observatory. And it was found that the secular variations of the areal dilatations had the chara cteristic change in common to all stations, and that these changes moved with the velocity of about 30 km/year to the direction from SW to NE, that is, in order of Oura, Donzurubo, Amagase and Iwakura.

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純粋な海面上昇速度を評価するために電子基準点データを用いて速度を求めた.これによる速度は加藤・津村 (1979) の方法による値と最大7mm/yの差異があった.の影響を除くと1970年以降の33年平均では日本沿岸全域で海面は低下傾向であったが, 海水温の上昇が顕著となった1985年以降は, 北部太平洋沿岸の一部を除いて最大1.2mm/yの海面上昇が生じている. 月別の朔望満潮位は9月が最高となり, H. W. Lに比べても10-20cm高い. また9月の朔望満潮位の経年変化は平均海面と同様, 1985年以降上昇傾向となり, 西日本沿岸でその傾向が強い.

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At the Miyazaki Crustal Movement Observatory, data acquisition and analysis for observation network of crustal activities are executed on multi-computers system. This data processing system is operated with a view to detect the phenomena related to the occurrence of earthquakes at Hyuganada. Analysis of data by extensometers at the Miyazaki observatory reveals an abnormal extension in E3 component 6 hours before the occurrence of the earthquake on March 18, 1987 (M=6.6). It is also suggested that the earth tides in E3 data are magnified slightly after rainfalls.

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　本稿では,地震予知を目的とした国土地理院の各種事業について概観し,国土地理院による観測の現況と計画について論じる.また,国土地理院による,これまでのGPS観測の成果を示し,今後の観測におけるGPSの応用の可能性につて議論する.

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The Earthquake SAR Analysis Working Group is a group of experts which was established under the Coordinating Committee for Earthquake Prediction in order to detect detailed coseismic ground surface deformation through analyses of SAR images of the Advanced Land Observing Satellite-2 (ALOS-2), develop related techniques, solve seismogenic mechanism from the deformation field and seek ways to utilize SAR data for disaster response and mitigation. Once an earthquake occurs and it is expected to cause coseismic deformation, ALOS-2 urgently observes the affected area upon request from the working group and Japan Aerospace Exploration Agency (JAXA) promptly provides the observation data to members of the working group. Geospatial Information Authority of Japan (GSI), the Secretariat of the working group, has analyzed the data and successfully detected detailed ground surface deformation caused by a lot of earthquakes including the 2014 North Nagano Prefecture Earthquake, the 2015 Nepal (Gorkha) Earthquake and the 2016 Kumamoto Earthquake.

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Results of continuous observation made at the Fujigawa Crustal Movement Observa tory for the period from July 1970 to December 1975 are described in the present paper. The Observatory is equipped with three components of extensometers (EXT), two com ponents of water-tube tiltmeters (WTT) and a set of borehole tiltmeters (BHT). Main features of the results are as follows : (1) Two modes of transient movements were recorded in the initial period of the observation . One is characterized with rapid movements of duration about half a year, as noticed on ground contraction (EXT-2 and EXT-3) and on inclination (BHT-2) . This mode may be attributed to artificial causes due to tunnel excavation and others . The other is more gradual in time duration of about two years, as indicated by ground contraction (EXT-2 and EXT-3) and by monotoni WSW-down tilting (WTTs) . (2) The EXT-1 started to record a large amplitude variation both in secular change and in short-period movements suddenly in November 1973. It may be attributed to a change in underground water pressure conditions, resulting in amplification of the strain changes. (3) Secular movements of the BHTs are inconsistent with those of the WTTs both in amplitude and in direction . From this, it is considered that a BHT, which records the tidal events nicely, is less reliable than a WTT so far as the long-term movements are concerned. However, the change in tilting modes of the BHTs may have some meanings . (4) The ground strain has ac cumulated at an average strain rate of about 0.4×10^-6/year in a general sense of extension in NS-direction and contraction in EW-direction . These trends are parallel to strike and dip directions of the surrounding geologic structures, respectively. (5) The ground tilt has accumulated in a general sense of WSW-down, which was especially active in the first two years of the observation, and less active thereafter. Although the tilting rate is not unif ornn, its average rate throughout the period is approximately 0.5×10^-6/year. -(6) The results obtained here with the EXTs, WTTs and BHTs do not seem to harmonize precisely with those from triangulations and levellings . But, it is too early to draw any definite conclusion now, as the present events on the instruments are still transient. (7) A remarkable change in strain and tilt accumulations was observed in 1973. Anomalous changes of similar modes in the same period have been reported, independently by several other observatories in Japan . This might support the idea that the modes of crustal deformations may vary almost simultaneously in the whole of Japan, as previously hypothesized by SHICHI.

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Abstract By processing JERS-1/SAR data with a technique called Interferometric SAR (INSAR), we succeeded in quantifying cruatal movement due to the NW Kagoshima Prefecture Earthquake (M6.3) of March 26, 1997. These outcomes agree with the crustal movement obtained from a field survey.
It can be concluded that the observation data from JERS-1 SAR make it possible to quantitatively measure crustal movement due to earthquake.

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