scholarly journals Chemosynthetic fossil molluscan faunas from the Neogene Taishu Group, distributed in Tsushima Islands, Nagasaki Prefecture, the southwest Japan

10.5109/19194 ◽  
2011 ◽  
Vol 32 (3) ◽  
pp. 11-26
Author(s):  
Takashi Ninomiya
Keyword(s):  
Southwest Japan ◽  
Nagasaki Prefecture

Hatching Dates of the Japanese Flounder Settling at Yanagihama Beach in Nagasaki Prefecture, Japan

1994 ◽  
Vol 60 (4) ◽  
pp. 369-372 ◽  
Author(s):  
Tetsuhisa Noichi ◽  
Teruko Matsuo ◽  
Tetsushi Senta
Keyword(s):  
Japanese Flounder ◽  
Nagasaki Prefecture

Trichophyton tonsurans Infection in Nagasaki Prefecture

2009 ◽  
Vol 71 (4) ◽  
pp. 434-437 ◽  
Author(s):  
Kizou HONMA ◽  
Katsutaro NISHIMOTO ◽  
Motoi TAKENAKA
Keyword(s):  
Trichophyton Tonsurans ◽  
Nagasaki Prefecture

Characterization of groundwater based on δ2H, δ18O and Cl− concentration beneath the Osaka Plain, Southwest Japan

2019 ◽  
Vol 53 (4) ◽  
pp. 235-247
Author(s):  
Tsuyoshi Shintani ◽  
Harue Masuda ◽  
Kaori Okazaki ◽  
Emilie Even ◽  
Masahiko Ono ◽  
...  
Keyword(s):  
Southwest Japan

COASTAL ALTERATION AND CHANGES IN SHORELINE MORPHOLOGY DUE TO ARTIFICIAL STRUCTURES IN MIIRAKU TOWN ON FUKUE IS. IN THE GOTO ARCHIPELAGO

2017 ◽  
Author(s):  
Ryo Sakamoto ◽  
Ryo Sakamoto ◽  
Satoquo Seino ◽  
Satoquo Seino ◽  
Hirokazu Suzaki ◽  
...  
Keyword(s):  
Tang Dynasty ◽  
National Park ◽  
Survey Methods ◽  
Aerial Photographs ◽  
Sand Transport ◽  
The Status ◽  
The Tang Dynasty ◽  
Coastal Changes ◽  
Century Poetry ◽  
Nagasaki Prefecture

A construction of breakwaters and other shoreline structures on part of a coast influences drift sand transport in the bay, and causes comprehensive topographic changes on the beach. This study investigated shoreline and coastal changes, taking as an example of Shiraragahama Beach in Miiraku on the northwestern end of Fukue Island, Nagasaki Prefecture (Kyushu, Japan). Miiraku, adjacent to Saikai National Park, appears in the revered 8th century poetry collection “Manyoshu” and served as a port for a ship taken by the Japanese envoy to China during the Tang Dynasty (618-709). Because of the recent development of breakwaters for a fishing harbor, the shore environments of this beach have changed significantly. In this study, the status of silt deposits and topographic changes on this beach arising from the construction of a harbor breakwater were evaluated by comparing aerial photographs taken in different years. Next, the changes in the shoreline visible from aerial photographs from 1947 to 2014 were analyzed. Lastly, the altitude of the beaches was measured using accurate survey methods. The following results were obtained: 1) coastal erosion made rock cliffs to fall off along the shore and deposited sand on this beach; 2) the more serious advances or retreats of the shoreline took place around shoreline structures; 3) sandbars and beach cliffs were formed.

scholarly journals Driving stress and seismotectonic implications of the 2013 Mw5.8 Awaji Island earthquake, southwestern Japan, based on earthquake focal mechanisms before and after the mainshock

2020 ◽  
Vol 72 (1) ◽  
Author(s):  
Kazutoshi Imanishi ◽  
Makiko Ohtani ◽  
Takahiko Uchide
Keyword(s):  
Stress Field ◽  
Stress Tensor ◽  
Nankai Trough ◽  
Source Region ◽  
Local Scale ◽  
Southwest Japan ◽  
Stress Tensor Inversion ◽  
Earthquake Fault ◽  
Reverse Faulting ◽  
Before And After

Abstract A driving stress of the Mw5.8 reverse-faulting Awaji Island earthquake (2013), southwest Japan, was investigated using focal mechanism solutions of earthquakes before and after the mainshock. The seismic records from regional high-sensitivity seismic stations were used. Further, the stress tensor inversion method was applied to infer the stress fields in the source region. The results of the stress tensor inversion and the slip tendency analysis revealed that the stress field within the source region deviates from the surrounding area, in which the stress field locally contains a reverse-faulting component with ENE–WSW compression. This local fluctuation in the stress field is key to producing reverse-faulting earthquakes. The existing knowledge on regional-scale stress (tens to hundreds of km) cannot predict the occurrence of the Awaji Island earthquake, emphasizing the importance of estimating local-scale (< tens of km) stress information. It is possible that the local-scale stress heterogeneity has been formed by local tectonic movement, i.e., the formation of flexures in combination with recurring deep aseismic slips. The coseismic Coulomb stress change, induced by the disastrous 1995 Mw6.9 Kobe earthquake, increased along the fault plane of the Awaji Island earthquake; however, the postseismic stress change was negative. We concluded that the gradual stress build-up, due to the interseismic plate locking along the Nankai trough, overcame the postseismic stress reduction in a few years, pushing the Awaji Island earthquake fault over its failure threshold in 2013. The observation that the earthquake occurred in response to the interseismic plate locking has an important implication in terms of seismotectonics in southwest Japan, facilitating further research on the causal relationship between the inland earthquake activity and the Nankai trough earthquake. Furthermore, this study highlighted that the dataset before the mainshock may not have sufficient information to reflect the stress field in the source region due to the lack of earthquakes in that region. This is because the earthquake fault is generally locked prior to the mainshock. Further research is needed for estimating the stress field in the vicinity of an earthquake fault via seismicity before the mainshock alone.

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