Field Survey of Tsunami Effects in Sri Lanka due to the Sumatra-Andaman Earthquake of December 26, 2004     

Shusaku Inoue  Anil C. Wijeyewickrema  Hiroyuki Matsumoto  Hiroyuki Miura  Priyantha Gunaratna  Manoj Madurapperuma  Toru Sekiguchi 《Pure and Applied Geophysics》2007,164(2-3):395-411

The December 26, 2004 Sumatra-Andaman earthquake that registered a moment magnitude (M_w) of 9.1 was one of the largest earthquakes in the world since 1900. The devastating tsunami that resulted from this earthquake caused more casualties than any previously reported tsunami. The number of fatalities and missing persons in the most seriously affected countries were Indonesia - 167,736, Sri Lanka - 35,322, India - 18,045 and Thailand - 8,212. This paper describes two field visits to assess tsunami effects in Sri Lanka by a combined team of Japanese and Sri Lankan researchers. The first field visit from December 30, 2004 – January 04, 2005 covered the western and southern coasts of Sri Lanka including the cities of Moratuwa, Beruwala, Bentota, Pereliya, Hikkaduwa, Galle, Talpe, Matara, Tangalla and Hambantota. The objectives of the first field visit were to investigate the damage caused by the tsunami and to obtain eyewitness information about wave arrival times. The second field visit from March 10–18, 2005 covered the eastern and southern coasts of Sri Lanka and included Trincomalee, Batticaloa, Arugam Bay, Yala National Park and Kirinda. The objectives of the second visit were mainly to obtain eyewitness information about wave arrival times and inundation data, and to take relevant measurements using GPS instruments.  相似文献   

How to cut a sediment core for <Superscript>210</Superscript>Pb geochronology: a supplement     

Xueqiang?LuEmail author  Eiji?Matsumoto 《Environmental Geology》2005,49(2):251-252

To obtain the profile of excess ²¹⁰Pb in sediment column, it is necessary to section the collected core to date. Sectioning thickness is generally not explicit. An approach when sedimentation rate is constant has been suggested by Lu and Matsumoto (Environ Geol 47:804–810, 2005). This paper addresses the case when sedimentation rate is variable. Actually, it is possible to assume that sedimentation rate is constant within the sectioning thickness and based on this concept, a tentative approach for determining reasonable sectioning thickness is proposed.  相似文献   

Lake sediment records on climate change and human activities since the Holocene in Erhai catchment,Yunnan Province,China   总被引：16，自引：1，他引：15  

R. Matsumoto 《中国科学D辑(英文版)》2005,48(3):353-363

Climate of Yunnan Plateau is mainly controlledby the system of southwest Asian monsoon, and alsoaffected by westerlies and local climate of the Qing-hai-Tibet Plateau. Since the Cenozoic, a large numberof structural lake basins have formed with the uplift ofthe Qinghai-Tibet Plateau[1]. As the information aboutthe climate and environment change was faithfullydocumented in lake sediments, which have the char-acteristics of continuity, high resolution, abundant in-formation, lake sediments p…  相似文献   

Functional equations in emitting atmospheres     

Matsumoto  Masamichi 《Astrophysics and Space Science》1978,59(2):373-387

Astrophysics and Space Science - Starting with the equation of transfer in a plane-parallel inhomogeneous atmosphere which emits and scatters radiation anisotropically, we obtain a set of...  相似文献   

Numerical Simulation of Accretion Discs in Close Binary Systems andDiscovery of Spiral Shocks     

Takuya Matsuda  Makoto Makita  Hidekazu Fujiwara  Takizo Nagae  Kei Haraguchi  Eiji Hayashi  H.M.J. Boffin 《Astrophysics and Space Science》2000,274(1-2):259-273

The history of hydrodynamic numerical simulations for accretion disks in close binary systems is reviewed, in which emphasis is placed, in particular, on the facts that spiral shock waves were numerically found in 1986 by researchers including one of the present authors and that spiral structure was discovered in IP Pegasi in 1997 by Steeghs et al. The results of our two and three-dimensional numerical simulations in recent years are then summarized, with comparison being made with observations. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

The variability of Magellanic cluster infrared stars     

S. Nishida  T. Tanabé  Y. Nakada  S. Matsumoto  K. Sekiguchi  I. S. Glass 《Monthly notices of the Royal Astronomical Society》2000,313(1):136-140

We report on the light variations of the infrared stars that were discovered recently in the Magellanic clusters NGC 419, 1783 and 1978. Their periods, of 528, 458 and 491 days, are among the longest known for carbon-rich Mira variables in the Clouds. All three IR stars were found to lie on the extension of the period– M _bol relation derived from the shorter-period C-rich Miras while they were 0.45–0.70 mag fainter than the extension of the period– M _K relation. Their main sequence masses were determined by isochrone fitting to be 1.5–1.6 M_⊙, consistent with the prediction of the evolutionary models of Vassiliadis & Wood.  相似文献   

Two- and three-dimensional numerical simulations of accretion discs in a close binary system     

Makoto Makita  †  Kenji Miyawaki  Takuya Matsuda 《Monthly notices of the Royal Astronomical Society》2000,316(4):906-916

We perform 2D and 3D numerical simulations of an accretion disc in a close binary system using the simplified flux vector splitting (SFS) finite volume method. In our calculations, the gas is assumed to be ideal with γ =1.01, 1.05, 1.1 and 1.2 . The mass ratio of the mass-losing star to the mass-accreting star is unity. Our results show that spiral shocks are formed on the accretion disc in all cases. In 2D calculations we find that the smaller γ is, the more tightly the spiral winds. We observe this trend in 3D calculations as well in a somewhat weaker sense. Mach numbers in our discs are less than 10. These values are lower than the values in observed accretion discs in close binary systems.
Recently, Steeghs, Harlaftis & Horne found the first convincing evidence for spiral structure in the accretion disc of the eclipsing dwarf nova binary IP Pegasi, using the technique known as Doppler tomography. Although the Mach numbers in present calculations are rather low, we may claim that the spiral structure that we discovered in earlier numerical simulations is now found observationally.  相似文献   

El Niño-related sea surface elevation and ocean bottom pressure enhancement associated with the retreat of the Oyashio southeast of Hokkaido,Japan     

Hasegawa  Takuya  Nagano  Akira  Matsumoto  Hiroyuki  Ariyoshi  Keisuke  Wakita  Masahide 《Marine Geophysical Researches》2019,40(4):505-512

  相似文献   

Mineralogical alteration of a type A CAI from Allende CV3 chondrite: Formation of secondary dmisteinbergite and its phase transition to anorthite     

Yuma Enokido  Tomoki Nakamura  Megumi Matsumoto  Akira Miyake  Takazo Shibuya  Changkun Park  Mike Zolensky 《Meteoritics & planetary science》2023,58(3):405-420

Dmisteinbergite, a hexagonal form of CaAl₂Si₂O₈, was found in a compact type A Ca-Al-rich inclusion (CAI) in the Allende CV3 chondrite. Scanning and transmission electron microscopic observations show that dmisteinbergite was always in contact with grossular and grossular was in contact with melilite. In addition, there is a crystallographic relationship between dmisteinbergite and anorthite. Based on the textural and crystallographic evidence, the following mineralogical alteration processes are proposed to have occurred in the CAI. (1) Melilite was replaced by grossular. High densities of vesicles in the grossular indicate that hydrogrossular might have been the primary alteration phase and dehydrated by later metamorphism. (2) Dmisteinbergite formed from (hydro)grossular through a reaction with Si-rich fluid. (3) Nano-sized minerals are formed within dmisteinbergite. (4) Dmisteinbergite was transformed to anorthite. (5) Both anorthite and dmisteinbergite were altered to nepheline. (6) Hydrogrossular was dehydrated to grossular. (Hydro)grossular, dmisteinbergite, anorthite, and nepheline in the CAI seem to have formed in the course of metasomatism that occurred in the Allende parent body. Except for the hydrogrossular dehydration, these reactions could have occurred at moderate temperature (200–250°C) in high pH fluids (pH 13–14) according to past experimental studies. Episodic changes in fluid composition seem to have occurred before reactions (2), (4), and (5), because these reactions were not completed before the next reaction started. Higher temperature is required for reactions (5) and (6) to occur. Our observation of the CAI suggests that it experienced multiple episodes of metasomatism as temperatures were rising in the Allende parent asteroid.  相似文献   

Orbit determination of the SELENE satellites using multi-satellite data types and evaluation of SELENE gravity field models   总被引：1，自引：0，他引：1  

S. Goossens  K. Matsumoto  D. D. Rowlands  F. G. Lemoine  H. Noda  H. Araki 《Journal of Geodesy》2011,85(8):487-504

The SELENE mission, consisting of three separate satellites that use different terrestrial-based tracking systems, presents a unique opportunity to evaluate the contribution of these tracking systems to orbit determination precision. The tracking data consist of four-way Doppler between the main orbiter and one of the two sub-satellites while the former is over the far side, and of same-beam differential VLBI tracking between the two sub-satellites. Laser altimeter data are also used for orbit determination. The contribution to orbit precision of these different data types is investigated through orbit overlap analysis. It is shown that using four-way and VLBI data improves orbit consistency for all satellites involved by reducing peak values in orbit overlap differences that exist when only standard two-way Doppler and range data are used. Including laser altimeter data improves the orbit precision of the SELENE main satellite further, resulting in very smooth total orbit errors at an average level of 18 m. The multi-satellite data have also resulted in improved lunar gravity field models, which are assessed through orbit overlap analysis using Lunar Prospector tracking data. Improvements over a pre-SELENE model are shown to be mostly in the along-track and cross-track directions. Orbit overlap differences are at a level between 13 and 21 m with the SELENE models, depending on whether 1-day data overlaps or 1-day predictions are used.  相似文献