Geomorphic reconstruction of formation and recession processes of waterfalls of the Kaminokawa river basin on Osumi Peninsula,southern Kyushu,Japan

To assess the geomorphological importance of waterfall recession in volcanic bedrock, we examined recession rates of six waterfalls in the lower reaches of Kaminokawa river basin on the Osumi Peninsula in southern Kyushu. The examination was performed with an empirical equation that uses a dimensionless parameter obtained by dimensional analysis of relevant measured factors, including erosive force, size of waterfall, and bedrock resistance. Welded Ata ignimbrite, formed at approximately 110 ka, may have played an initiating role to maintain such waterfalls because it resists weathering more than other local rocks. Estimated recession rates for the six waterfalls range from 0.2 to 3.0 cm/y, which compare with estimated rates for waterfalls in another region characterised by welded ignimbrite. Comparison of equation‐derived recession rates of waterfalls with actual recession distances from confluences supports the idea that an original waterfall will subsequently split into two distinct waterfalls when it recesses past an upstream junction of two channels. Our findings revealed that all six waterfalls likely would have been at almost the same point lower in the watershed in the past, marking the general site of the original waterfall. Moreover, the ancestral original waterfall is highly likely to have started from a point between the caldera rim and present river mouth. There, a knickpoint was likely caused by the river dropping into an inner part of the caldera, possibly just after the eruption of the Ata ignimbrite. The waterfall erodes upstream away from the caldera basin, and this happens to be to the east.     

From Atomic Fragments to Memories of the Trinity Bomb: A Bridge of Oral History over the Pacific

This paper first introduces the background of the making ofMemories of the Trinity Bomb, a Japanese documentary film basedon the book Atomic Fragments: A Daughter's Questions, authoredby Mary Palevsky. Yoshihiko Muraki, an independent filmmaker,revealed his unique approach in filming the spiritual journeyof Mary, a daughter of the Manhattan Project scientists, inher search of the true meaning of the atomic bomb. While thedocumentary primarily focused on the narratives of Mary Palevskyand several Project scientists, this paper introduces Japaneseperspectives on the film through interviews with Japanese viewersvarying both in generation and background. Through this endeavor,the paper explores the meaning of this trans-media as well astransnational collaboration on the topic of the atomic bomb,which remains at the crossroads of history and personal memories.     

Reck,Christiane, Mitteliranische Handschriften Teil I: Berliner Turfanfragmente manichäischen Inhalts in soghdischer Schrift. [Verzeichnis der Orientalischen Handschriften in Deutschland Band XVIII, 1].

Indo-Iranian Journal -     

Long‐term stability of fracture systems and their behaviour as flow paths in uplifting granitic rocks from the Japanese orogenic field

In granitic rocks, fracture networks typically provide pathways for groundwater flow and solute transport that need to be understood to assess the long‐term performance of deep underground storage or disposal facilities such as radioactive waste repositories. However, relatively little is known about the long‐term processes of fracturing and/or the longevity of flow paths (FP) in granitic rocks distributed within orogenic belts. To clarify these issues, Japanese plutons of different ages and in situ fractures in granite at the Mizunami Underground Research Laboratory (MIU) located in central Japan were studied. Detailed structural characterization and geochemical analysis of in situ fracture fillings sampled from a depth of 300 m were carried out to clarify the relationship between fracturing and mineral infilling processes. Different plutons show identical episodes of fracturing and fracture filling, consisting of: brittle tensile fracturing, due to decreasing temperature through the ductile–brittle transition after plutonic intrusion (Stage I); relatively rapid uplifting (ca. a few mm/year) accompanied by hydrothermal water circulation, which produced uncrushed layered mineral fillings (Stage II); and a period of low‐temperature meteoric water circulation following exposure after uplift (Stage III). The parageneses of carbonate mineral fracture fillings and their carbon isotopic compositions (¹⁴C, δ¹³C) show that there were distinct episodes of carbonate mineral precipitation during the rapid uplifting of a pluton. The carbonate minerals that formed during each episode incorporated carbon from a distinct source. The evolution of fillings identified here enables development of a specific model of fracturing and persistence of fluid‐conducting systems in the plutons of the orogenic field.     

Gender geography in Japan: the trajectory,fruits of research and future challenges

Abstract

The indication by female geographers outside of Japan that, due to the original dearth of female geographers, a gender perspective had been missing from geography held true for Japan as well. In 1993, Yoshida was the first person to discuss the importance of a gender perspective in a Japanese journal of geography. Nearly 25 years have passed since its publication, and the aim of this paper is to investigate what developments have taken place in Japanese geography on gender research. As the accomplishments of feminist geography in English-speaking countries was merely ‘imported’ to Japan around 1990, there is no firm starting point of ‘feminist’ geography, which originated in women’s liberation movement of the 1970s, in the country. Rather, it can be said that Japanese geographers, regardless of sex, undertake gender geography, which does not limit a particular sex as the sole subject and/or object of research. The results of research on gender geography by men geographers began to appear from the year 2000. The use of life history method emerged as a trend in research since 2000. While there has been gradual progress in research on gender geography in Japan, the number of researchers are still by no means large. While Japanese geography has hitherto involved a one-way absorption of the fruits of overseas research on gender/feminist geographies, at least based on studies that have already accumulated in Japan, it is now necessary that Japanese study results also be communicated to overseas.