| FullText URL | esr_025_contents.pdf |
|---|---|
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2018-12-27 |
| Volume | volume25 |
| Issue | issue1 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2018 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| FullText URL | esr_026_cover.pdf |
|---|---|
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2019-12-27 |
| Volume | volume26 |
| Issue | issue1 |
| ISSN | 1340-7414 |
| language | English |
| Copyright Holders | © 2019 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| FullText URL | esr_026_titlepage.pdf |
|---|---|
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2019-12-27 |
| Volume | volume26 |
| Issue | issue1 |
| ISSN | 1340-7414 |
| language | English |
| Copyright Holders | © 2019 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| JaLCDOI | 10.18926/ESR/58574 |
|---|---|
| Title Alternative | Computation of non-linear site response by the time-domain finite-difference method |
| FullText URL | esr_026_001_017.pdf |
| Author | TORIGOE, Yusuke| KOMATSU, Masanao| TAKENAKA, Hiroshi| |
| Abstract | We have developed a time-domain staggered-grid finite-difference code for modeling non-linear response of a one-dimensionally inhomogeneous subsurface structure to a SH plane-wave incidence. It employs the velocity-stress formulation of elastodynamic equation for the linear part, and adopts a elastoplastic rheology model for the non-linear relation between the stress and strain. In this paper, we apply this code to four constitutive models from linear-elastic to nonlinear: (1) linear elastic model, (2) linear viscoelastic model, (3) elastoplastic model, and (4) viscoelastoplastic model, which simulate shallow sand and clay structures and are vibrated by a vertically incident SH plane-wave of Ricker wavelet, to compare the linear and the non-linear soil behaviors including low strains damping (viscoelastic effect) and/or hysteretic attenuation (non-linear effect). We also apply it to a local strong-motion record of the 2000 Western-Tottori earthquake (MW6.8). We then simulate characteristics of non-linear site response such as reduction of the spectral amplitude in the high frequency band and shift of the peak frequencies to lower frequencies. |
| Keywords | finite-difference method non-linear site response strong motion |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2019-12-27 |
| Volume | volume26 |
| Issue | issue1 |
| Start Page | 1 |
| End Page | 17 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2019 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| JaLCDOI | 10.18926/ESR/58575 |
|---|---|
| Title Alternative | Schistose fault related rocks from the Sangun Metamorphic Rocks, Kawakita area, Misaki Town, Okayama Prefecture, SW Japan |
| FullText URL | esr_026_019_024.pdf |
| Author | MATSUSHITA, Mirei| SUZUKI, Shigeyuki| |
| Abstract | The crystalline schist which is representatively exposed in the Innerside of Southwest Japan is called the Sangun Metamorphic Rocks (SMR). In Kawakita area, Misaki Town, Okayama Prefecture, schistose fault rocks which is newly described in below are intercalated in the SMR. The rocks are composed of lenticular fragments of pelitic, basic siliceous rocks and quartz vein with siliceous to pelitic matrix. The fine-grained muscovites which define schistosity penetrate the rocks. Major direction of layer which though to reflect slip plane is subparallel to the schistosity. The long axis of some fragments are slightly oblique to the schistosity. The combination of the two sets of planes is considered to be a composite planar fabric. These occurrences suggest that the rocks are fault rock before the Sangun Metamorphism and named as schistose fault rocks. Lenses of cataclasite and myronite are accompanied. Planar thin (about 10cm in thickness) brittle fault rock is also associated. These shear deformed rocks form units of layer (shear zone) of 10 to 100m in thickness, and are concordantly intercalated in the surrounded normal schists. Active periods of the shear zones had several times from before and after the event of the Sangun Metamorphism. |
| Keywords | Sangun Metamorphic Rocks regional metamorphism shear deformation schistose fault rock |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2019-12-27 |
| Volume | volume26 |
| Issue | issue1 |
| Start Page | 19 |
| End Page | 24 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2019 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| JaLCDOI | 10.18926/ESR/58576 |
|---|---|
| Title Alternative | Interdisciplinary ESD lesson study for the university students with attention to the difference of climate and seasonal feeling in “summer” among Germany, northern Europe and Japan |
| FullText URL | esr_026_026_036.pdf |
| Author | KATO, Kuranoshin| KATO, Haruko| OTANI, Kazuo| MATSUMOTO, Kengo| |
| Abstract | Climatological features and seasonal feeling in the season called by the same word such as “summer”would be rather different from region to region. Comparison of these features among the different regions, including the regions which are not so familiar to the students, would help to promote their fundamental ESD literacy, especially relating to the “Understanding of heterogeneous others”. Based on that concept, this paper will report an interdisciplinary lesson study for the university students on a theme how different the summertime climate and seasonal feeling among Germany, northern Europe and Japan are. In this study, the lesson practice was made in 2015 and 2018. In both classes, after the lecture on the summertime climate and seasonal feeling in these regions, the students created substitute songs with use of the melody of “Alles neu macht der Mai” (“The May makes all things new”, the same melody as a Japanese school song “Butterfly”) for the comparison between Germany and Japan. As for that between northern Europe, the melody of a Japanese school song “Furu-Sato” (“My country home”) was used for the creation of the substitute songs. It is noted that, not only the seasonal mean temperature or solar radiation condition, but also the features in association with the large day-to-day temperature variation was strongly reflected in the students’ works. |
| Keywords | Interdisciplinary collaboration between climate and cultural understanding education ESD Comparative climatology Regional difference of summer climate |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2019-12-27 |
| Volume | volume26 |
| Issue | issue1 |
| Start Page | 25 |
| End Page | 36 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2019 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| JaLCDOI | 10.18926/ESR58577 |
|---|---|
| Title Alternative | Synoptic climatological analyses of daily precipitation features and atmospheric fields in warm season relating to the precipitation difference between Kochi and Okayama characterizing the Seto Inland Sea Climate in Japan |
| FullText URL | esr_026_037_049.pdf |
| Author | Kato, Kuranoshin| SUGIMURA, Yuki| MATSUMOTO, Kengo| |
| Abstract | In order to re-examine the formation process of the climatological precipitation difference between Kochi (Pacific side of Shikoku District) and Okayama (Seto Inland Sea side) characterizing the Seto Island Sea Climate in warm season, synoptic climatological analyses of the daily precipitation features and atmospheric fields were performed for the warm season (April to September) of 1985 - 2015, based on the daily and hourly precipitation data and weather maps by the Japan Meteorological Agency (JMA), and the NCEP/NCAR re-analysis data. The large climatological difference of precipitation at Kochi from that at Okayama throughout the warm season was greatly contributed to by the days with the precipitation difference between Kochi and Okayama (ΔPR) with greater equal to 30 mm/day. In addition, such large daily ΔPR was mainly due to the intense rainfall at Kochi with greater equal to 10mm/h throughout the warm season, except for a part of the cases in April when the “not so intense rain” with less than 10mm/h at Kochi contributed to the large ΔPR. However, it is noted that the features of the synoptic-scale atmospheric fields and possible roles of the mountain ranges in Shikoku District causing the large ΔPR were rather different among August (midsummer), September (Autumn rainfall season) and April (Spring) . |
| Keywords | Daily precipitation climatology Climate around Japan Seto Inland Sea Climate in Japan Synoptic climatology |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2019-12-27 |
| Volume | volume26 |
| Issue | issue1 |
| Start Page | 37 |
| End Page | 49 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2019 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| FullText URL | esr_026_colophon.pdf |
|---|---|
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2019-12-27 |
| Volume | volume26 |
| Issue | issue1 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2019 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| FullText URL | esr_026_cover_j.pdf |
|---|---|
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2019-12-27 |
| Volume | volume26 |
| Issue | issue1 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2019 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| FullText URL | esr_027_cover.pdf |
|---|---|
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2021-03-31 |
| Volume | volume27 |
| Issue | issue1 |
| ISSN | 1340-7414 |
| language | English |
| Copyright Holders | © 2021 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| FullText URL | esr_027_titlepage.pdf |
|---|---|
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2021-03-31 |
| Volume | volume27 |
| Issue | issue1 |
| ISSN | 1340-7414 |
| language | English |
| Copyright Holders | © 2021 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| JaLCDOI | 10.18926/ESR/61954 |
|---|---|
| Title Alternative | For development of an ESD-based teacher training program on climate change : overlooking geo-phenomena on various timescales |
| FullText URL | esr_027_001_017.pdf |
| Author | Kato, Yuji| Kato, Kuranoshin| |
| Abstract | Since the recent climate change is an important topic in the context of SDGs (Sustainable Development Goals) and ESD (Education for Sustainable Development), teacher training course should produce educators with sufficient geo-literacy. In order to meet this requirement, the authors have designed a study plan that facilitates students’ better understanding of current climate change issues, which will be offered in a lecture at university by two speakers who have different specialties, paleoenvironmental science and meteorology. Summary of the lecture is as follows. At first, from the branch of paleoenvironmental science, a major cooling event at the Eocene/Oligocene boundary and the glacial-interglacial cycles in the Quaternary will be explained. We will then instruct the participants to compare these climatic events with recent global warming, in order to remind them of the extraordinary higher speed of the recent climate change than climatic events in the geological past. Followed by these global topics, climatological features in East Asia including Japan (e.g. regional/seasonal difference in climate and year-to-year variations) will be demonstrated in order to relate local issues to global ones. By these efforts, the lecture aims to cultivate students’ ability to grasp geophenomena from various aspects and understand the true nature of problems, which may contribute producing educators who can execute ESD programs. |
| Keywords | time scales geologic events paleoenvironmental science meteorology and climatology global warming ESD SDGs |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2021-03-31 |
| Volume | volume27 |
| Issue | issue1 |
| Start Page | 1 |
| End Page | 17 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2021 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| NAID | 120007037387 |
| JaLCDOI | 10.18926/ESR/61955 |
|---|---|
| Title Alternative | The Kibi Plateau Surface ― relationship with the Paleogene and Miocene deposits in middle western part of Okayama Prefecture, Japan ― |
| FullText URL | esr_027_019_027.pdf |
| Author | Tanaka, Hajime | Suzuki, Shigeyuki| |
| Abstract | The Kibi Plateau Surface is associated with the Paleogene gravel river bed deposits of the Kibi Group and the Miocene marine deposits of the Katsuta Group and the Bihoku Group. These Paleogene and Miocene units are valley fill deposits. The Kibi Group is composed of formations which is deposited by more than 7 different depositional events during earliest to latest Paleogene Period. Repeated cycles of “erosion - formation of new valley system - deposition and fill up the valley” created the low relief topographic surface. The deposition of the Miocene deposits might complete the Kibi Plateau Surface. Detailed field works have done in middle western part of Okayama Prefecture. The Kibi Plateau Surface in study area is gently dipping from NW (about 600m high) to SE (about 100m high). The distributions of the Paleogene and Miocene deposits fit the surface. At the southern margin of the Kibi Plateau, the surface is a little inclined (from 400m high to 100m high) where the bottom of paleo-valleys of the Paleogene deposits are subparallel to the surface. It suggests that the gentle tilting of the Kibi Plateau is caused by an up-warping. |
| Keywords | Kibi Plateau Surface Paleogene Neogene Miocene |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2021-03-31 |
| Volume | volume27 |
| Issue | issue1 |
| Start Page | 19 |
| End Page | 27 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2021 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| NAID | 120007037376 |
| JaLCDOI | 10.18926/ESR/61956 |
|---|---|
| Title Alternative | Synthetic nearfield seismograms at a subsurface position in a horizontally layered half-space |
| FullText URL | esr_027_029_038.pdf |
| Author | Takenaka, Hiroshi| Watanabe, Tomotsugu| |
| Abstract | We extend the computational code of Takenaka and Sasatani (2000) for synthetic nearfield seismograms for horizontally layered elastic media, based on the reflection/transmission matrices and the discrete wavenumber summation method, to calculate seismic motion and its spatial derivatives at a subsurface position in the attenuative media. In this paper we describe the theory of this extension and show some numerical examples to verify the extended code. |
| Keywords | synthetic seismogram reflectivity method layered half-space |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2021-03-31 |
| Volume | volume27 |
| Issue | issue1 |
| Start Page | 29 |
| End Page | 38 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2021 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| NAID | 120007037377 |
| JaLCDOI | 10.18926/ESR/61959 |
|---|---|
| Title Alternative | Estimation of displacement waveforms by baseline correction of near-fault acceleration records of the 2016 Kumamoto earthquake with median filter |
| FullText URL | esr_027_039_050.pdf |
| Author | Watanabe, Tomotsugu| Komatsu, Masanao| Takenaka, Hiroshi| |
| Abstract | The 2016 Kumamoto earthquake sequence occurred on April 14 (MJMA 6.5) and April 16 (MJMA 7.3). Seismic intensity of 7 on the Japan Meteorological Agency (JMA) scale was observed in Mashiki Town, Kumamoto Prefecture for the both events and in Nishihara Village, Kumamoto Prefecture for the April-16 event. We estimate the displacement waveforms from these acceleration records. Since the acceleration seismograms include the long-period noise due to tilting of the ground and instrumental effects, the baseline corrections are required to derive the accurate velocity and displacement waveforms. We apply a median filter to the velocity waveforms to identify the linear trends on them due to the steplike noise on the acceleration records, and determine the time at which baseline shifts take place and the step value of each shift for the baseline correction through trial and error. Our baseline correction can successfully reconstruct the velocity and displacement waveforms from the acceleration records. The displacement waveforms show the static components consistent with the geodetic data. |
| Keywords | 2016 Kumamoto earthquake baseline correction median filter displacement |
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2021-03-31 |
| Volume | volume27 |
| Issue | issue1 |
| Start Page | 39 |
| End Page | 50 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2021 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| NAID | 120007037380 |
| FullText URL | esr_027_colophon.pdf |
|---|---|
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2021-03-31 |
| Volume | volume27 |
| Issue | issue1 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2021 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
| FullText URL | esr_027_cover_j.pdf |
|---|---|
| Publication Title | Okayama University Earth Science Report |
| Published Date | 2021-03-31 |
| Volume | volume27 |
| Issue | issue1 |
| ISSN | 1340-7414 |
| language | Japanese |
| Copyright Holders | © 2021 by Okayama University Earth Science Reports Editorial Committee All Rights Reserved |
| File Version | publisher |
