- 著者
- Mitsuhiro MATSU'URA Takaya IWASAKI Yasunori SUZUKI Ryosuke SATO
- 出版者
- The Seismological Society of Japan, The Volcanological Society of Japan , The Geodetic Society of Japan
- 雑誌
- Journal of Physics of the Earth (ISSN:00223743)
- 巻号頁・発行日
- vol.28, no.2, pp.119-143, 1980 (Released:2009-04-30)
- 参考文献数
- 28
- 被引用文献数
- 30 53
An inverse method to find optimum fault parameters from geodetic data with random errors is extended so as to be applicable to a case of the data including a systematic error caused by movements of reference points in triangulation. Application of the new inverse method to static displacement data associated with the Kanto earthquake of 1923 yields a dislocation source model which adequately explains both the seismological and the geodetic data.From the geodetic data, it is found that the fault motion of the Kanto earthquake is a reverse, right-lateral slip of 4.8m with a slip-angle of 140° on a plane which dips 25° towards N24°E, where the slip-angle is measured counterclockwise from a strike on the fault plane. The fault length, width, and the depth to the upper fault margin are determined as 95km, 54km, and 1.5km respectively. The seismic moment and stress drop of this earthquake are estimated to be 8.4×1027 dyne·cm and 45 bars, respectively.Taking the static fault solution as the basic model, the dynamic process of the fracture is investigated on the basis of the long-period seismograms recorded at Hongo, Tokyo. The result shows that the rupture starts from a relocated hypocenter, 35.41°N, 139.22°E and 13.5km (depth), and extends outwards on the fault plane with a propagating velocity of the rupture front of 2.0km/sec. The rise time of the source time function is assumed to be 5.0sec. The maximum amplitude of acceleration for a frequency range of 0.0-3.3Hz at Tokyo is estimated to be about 280gal for the horizontal component and to be 60gal for the vertical component, by applying an empirical formula to the calculated ground displacements.
- 著者
- TAKAYA IWASAKI AKITAKA TONO KYOKO AOKI AKIHIRO SEO NORIAKI MURAKAMI
- 出版者
- The Japanese Society for Plant Systematics
- 雑誌
- Acta Phytotaxonomica et Geobotanica (ISSN:13467565)
- 巻号頁・発行日
- vol.61, no.1, pp.1-20, 2010-06-30 (Released:2017-03-21)
- 参考文献数
- 35
- 被引用文献数
- 1
A phylogeographic study of two species of Carpinus, C. japonica Blume and C. tschonoskii Maxim. (Betulaceae), based on the distribution patterns of their chloroplast DNA haplotypes, is reported. In Japan, these species are mainly distributed in Pacific-type deciduous broad-leaved forests. Using 439-440 and 627-629bp nucleotide sequences of noncoding regions of chloroplast DNA, we detected 5 and 6 haplotypes among 217 and 181 individuals sampled from 52 and 49 populations of C. japonica and C. tschonoskii, respectively. The geographic distribution patterns of the haplotypes were highly structured. We investigated the common phylogeographic patterns between the two species that would indicate the influence of common historical factors such as climate change since the last glacial maximum (LGM). Based on our results, we concluded that the Pacific-type Japanese deciduous broad-leaved forests were split into at least three refugia during the LGM. After the LGM, the species expanded to northern areas or moved to higher altitudes from each refugium, thus now occupying northeastern, central, and southwestern Japan.