scholarly journals Ti-Magnetite Crystallization in Melt Inclusions of Trachytic Rocks from the Dokdo and Ulleung Islands, South Korea: Implications for Hydrous and Oxidized Magmatism

Minerals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 644
Author(s):  
Inkyeong Moon ◽  
Hyunwoo Lee ◽  
Jonguk Kim ◽  
Jihye Oh ◽  
Donghoon Seoung ◽  
...  
Keyword(s):  
Melt Inclusions ◽  
Parent Magma ◽  
Late Cenozoic ◽  
Eurasian Plate ◽  
Japanese Archipelago ◽  
Mineral Phases ◽  
The Japanese Archipelago ◽  
Volcanic Islands ◽  
Back Arc

The Dokdo and Ulleung islands (Korea) are volcanic islands in the East Sea (Sea of Japan), formed in the late Cenozoic. These volcanic islands, in the back-arc basin of the Japanese archipelago, provide important information about magma characteristics in the eastern margin of the Eurasian plate. The origin of the Dokdo and Ulleung intraplate volcanism is still controversial, and the role of fluids, especially water, in the magmatism is poorly understood. Here, we comprehensively analyzed the melt inclusions (10–100 m in diameter) hosted in clinopyroxene phenocrysts of trachyte, trachyandesite, and trachybasalt. In particular, we observed Ti-magnetite and amphibole which were crystallized as daughter mineral phases within melt inclusions, suggesting that Ti-magnetite was formed in an oxidized condition due to H2O dissociation and H2 diffusion. The Ti-magnetite exhibited compositional heterogeneities of MgO (average of 8.28 wt %), Al2O3 (average of 8.68 wt %), and TiO2 (average of 8.04 wt %). The positive correlation of TiO2 with Cr2O3 is probably attributed to evolutionary Fe–Ti-rich parent magma. Correspondingly, our results suggested hydrous and oxidized magmatism for the Dokdo and Ulleung volcanic islands.

Anthropomorphic Clay Figurines of the Jomon Period of Japan

2017 ◽  
Author(s):  
Koji Mizoguchi
Keyword(s):  
Female Body ◽  
Human Life ◽  
Visual Representation ◽  
Well Being ◽  
The Body ◽  
Japanese Archipelago ◽  
Bodily Experiences ◽  
The Subject ◽  
The Japanese Archipelago

This chapter charts the trajectory of change of Jomon period clay anthropomorphic figurines in the Japanese archipelago. The earliest specimens embodied the perception of the body and female bodily experiences rather than accurately representing the body itself. Emphasis gradually shifted from the material embodiment of unmediated bodily perception and experiences to the visual representation of the body. Through this process, the subject of the representation expanded from the female body to the bodies of various categories of being, including animals and fantastic/supernatural beings, and the figurines came to embody the mutual transformability. These beings were networked to form an ‘animistic’ cosmology whose successful reproduction was metaphorically linked to that of human life and community. The decline of the symbolic role of the female reproductive faculty as the universal referent in the prayer for communal well-being led to the end of the Jomon clay anthropomorphic figurines.

Origin and formation of Yaponesians based on genome sequences

Impact ◽  
2020 ◽  
Vol 2020 (7) ◽  
pp. 56-58
Author(s):  
Naruya Saitou
Keyword(s):  
Population Genetics ◽  
Human Migration ◽  
Human Populations ◽  
Genome Sequences ◽  
Japanese Archipelago ◽  
Broad Term ◽  
The Japanese Archipelago ◽  
Ebb And Flow ◽  
National Institute Of Genetics

The ebb and flow of human migration across the planet can nowadays be probed with advanced archaeology, linguistics, anthropology and genomics. Together, these can provide a convincing picture of the various divergences and convergences of different human populations across vast areas. It is now possible to better understand how, why and where a particular group or society arose. Professor Naruya Saitou of the Population Genetics Laboratory at the National Institute of Genetics in Mishima has dedicated his career to the synthesis of these disciplines. The current focus of his research is on understanding the origins and formation of the Yaponesian people. This broad term was coined by writer Toshio Shimao in 1960s to encompass the diverse peoples of the Japanese Archipelago over its many thousands of years of inhabitation. Saitou's research is helping to uncover Japan's ancient past.

Geographical variation in the cranial and external characters of the little tube-nosed bat,Murina silvatica in the Japanese archipelago

2005 ◽  
Vol 50 (3) ◽  
pp. 309-322 ◽  
Author(s):  
Dai Fukui ◽  
Kishio Maeda ◽  
David A. Hill ◽  
Sumiko Matsumura ◽  
Naoki Agetsuma
Keyword(s):  
Geographical Variation ◽  
Japanese Archipelago ◽  
The Japanese Archipelago

Morphometric studies of polyploid Cardamine species (Brassicaceae) from Japan: solving a long-standing taxonomic and nomenclatural controversy

2010 ◽  
Vol 23 (2) ◽  
pp. 94 ◽  
Author(s):  
Judita Lihová ◽  
Hiroshi Kudoh ◽  
Karol Marhold
Keyword(s):  
Ploidy Level ◽  
Morphological Variation ◽  
East Asian ◽  
Species Boundaries ◽  
Morphometric Data ◽  
Evolutionary Mechanism ◽  
Taxonomic Treatment ◽  
Japanese Archipelago ◽  
Level Data ◽  
The Japanese Archipelago

Polyploidy is an important evolutionary mechanism and speciation mode in plants; however, delimitation of species boundaries in polyploid complexes is often a difficult task. In the present paper, we explore morphological variation in a group of East Asian Cardamine polyploids that have long been shrouded in taxonomic and nomenclatural confusion. We relate the present morphometric data of 41 sampled populations with recently published ploidy-level data, and propose a revised taxonomic treatment, including the designation of several lectotypes. The following species are recognised in Japan: C. schinziana O.E.Schulz (2n = 6x, 8x), C. torrentis Nakai (2n = 8x), C. valida (Takeda) Nakai (2n = 4x) and C. yezoensis Maxim. (2n = 6x−12x). C. amariformis Nakai (2n = 4x) from Korea is also discussed, although it may be conspecific with C. valida, pending further studies. Distribution of these taxa in the Japanese Archipelago is characterised, including comments on their occurrence outside of Japan.

Introduction of domestic animals to the Japanese archipelago

2017 ◽  
Author(s):  
Hitomi Hongo
Keyword(s):  
Twentieth Century ◽  
Dairy Products ◽  
Major Part ◽  
Domestic Animals ◽  
Domestic Species ◽  
Japanese Archipelago ◽  
Biological Studies ◽  
Chinese Continent ◽  
The Japanese Archipelago ◽  
Textual Records

Zooarchaeological and molecular biological studies indicate that all domestic animals found in Japan were introduced and local domestication of wild boar and wolf is unlikely. Timing of introduction and husbandry practice for dog, pig, horse, cattle, and chicken are discussed. These main domestic species were introduced from the Chinese continent in prehistoric times, probably via the Korean peninsula. Meat of domestic animals and dairy products were not a major part of the diet until the twentieth century ad, partly because of the Buddhist prohibition of the consumption of animal meat. Zooarchaeological data from the Yayoi and Kofun period sites as well as the historical era have been gradually accumulating, helping the interpretation of textual records as well as supplementing them.

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