Mineralogical descriptions are made for the Taishu hakudo and Taishu toseki which have been mined as refractory clay and a raw material for sanitary ware at Azu in the Tsushima Shimoshima Island, Nagasaki Prefecture, Japan. These ores were formed by hydrothermal alteration of quartz porphyry of Miocene age. X-ray powder diffraction, electron probe microanalysis and polarizing microscopy have revealed that the Taishu hakudo (white clay) is composed mainly of halloysite and the Taishu toseki (altered quartz porphyry) is composed of 2M₁ sericite, Ca-beidellite, albite, quartz, etc. with residual quartz and oligoclase.
The toseki is well jointed in the same direction with a vertical dip, and the alteration products are abundant along the fissures. Three types of alteration can be recognized at this deposit. The first alteration is characterized by the assemblage of albite, sericite and beidellite which crystallized in this order. This alteration is considered to have transformed quartz porphyry into toseki by pervasive alteration around the fissures subsequent to the igneous activity of the original quartz porphyry. The second alteration is characterized by the assemblage of FeMg-chlorite, sericite, calcite and galena and the assemblage of interstratified chlorite/vermiculite, sericite and quartz which were formed filling the fissures and disseminated in the toseki. The hydrothermal solution of this alteration may have a genetical relation to a granitic pluton near this deposit. The last alteration is intense halloysitization which affected the toseki pervasively around the fissures and formed the hakudo.

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The Middle Miocene Katsumoto Formation, distributed in the northern and central part of Iki Island, Nagasaki Prefecture, has been considered as a typical back-arc basin sequence. This study aims to describe sedimentary facies, ichinofacies and paleocurrent system and to discuss sedimentary environments and depositional systems. The Katsumoto Formation, attaining more than 450m in thickness, shows a coarsening- and thickening-upward sequence as a whole. It begins with mud-dominated facies of interbedded sandstone and mudstone, passes upward into medium-bedded, medium-grained sandstone and siltstone facies, and ends with thick-bedded, medium- to coarse-grained sandstone facies at top. Six sedimentary facies recognized. Their lithologies are summarized as follows; Facies A: mainly well-sorted, medium to very coarse sandstone with planer to tabular cross-stratification, Facies B: well-sorted, very fine to medium sandstone with amalgamated hummocky cross-stratification (HCS), Facies Ca: interbedded HCS sandstone and siltstone, Facies Cb: thinly interbedded HCS sandstone and siltstone, Facies D: mottled sandy siltstone with thin very fine-grained sandstone, Facies Fa: slump breccia, Facies Fb: slump folded thinly interbedded sandstone and mudstone, and Facies F: interbedded very fine-grained turbidite sandstone and mudstone. The sedimentary environments inferred from Facies A to F are summarized as follows; Facies A: upper shoreface, Facies B: lower shoreface, Facies Ca and Cb: inner shelf, Facies D: outer shelf, Facies Ea: shelf margin, Facies Eb: continental slope, and Facies F: basin plain. Fossil evidence, such as burrowing organisms and benthonic foraminiferas obtained from the formation, seems to coincide with these environments. Eastward and northeastward paleoflows are dominant in the lower, and the middle and upper parts of the formation, respectively. It can be concluded, therefore, that the Katsumoto Formation represents a facies succession from basin plain to tide-dominated shallow marine sediments due to northeastward progradation process. The northeastward progradation system is also recognized in the regional area of the Tsushima Basin in the Middle Miocene time.

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This report intend to recognize that the best way of tunnelling technologies always are harmonized with defficult social and natural conditions and we should consider in any area which have been relationship between social, economical, cultural efforts and transportation.
This technology have to consider environmental condition not only in construction stage but also after construction, also consider any natural conditions and these behavier.
By comparison between Europian and Japanese technologies, it is cleared how to resolve each recent and future problems and this is my consideration which were generated for a long years engaged both major project i.e. the SEIKAN Undersea Tunnel and the Channel Tunnel.

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The timing of igneous activity in the Amakusa area, the most southern part of the Inner Zone of Kyushu, was determined on two samples by K-Ar age dating (quartz porphyry: 16.7±0.3 Ma, granodiorite: 14.6±0.3 Ma). These and previous ages indicate that Miocene felsic igneous activity and continuous mafic igneous activity, composed of high Mg andesite, occurred between 19 and 14 Ma. Basalt activity took place at 10 and 7 Ma. The felsic and mafic igneous activity occurred intermittently at 1-3 m.y. intervals in the Amakusa area.
Miocene igneous activity was protracted more than 5 m.y. in the Amakusaarea and also elsewhere in the Inner Zone of Kyushu, for example, Tsushima (19-14 Ma), Goto (20-7 Ma) and Koshikijima (15-7 Ma). In contrast, the ages of Miocene igneous activity in the Outer Zone of Kyushu extend for only about 2 m.y., around 15-13 Ma, which indicates that the range of Miocene magmatic activity in the Inner Zone of Kyushu was longer than that in the Outer Zone. It is possible that differrent styles of magmatic activity occurred during the Miocene in the Inner and Outer Zone of Kyushu, i.e. back-arc and fore-arc tectonic settings, respectively. In the back-arc area the upper lithosphere expanded, became thin and fractured as a result of being pulled by the subducted lithosphere. After that, magma from the asthenosphere ascended intermittently along the cracks in the fractured upper lithosphere, which caused extensive and intermittent magmatic activity. This is one possible explanation why Miocene magmatic activity is protracted in the Inner Zone which was a back-arc area.
The Miocene magmatic activity in the Tsushima and Goto area started at 20-18 Ma, which is almost the same time when the Sea of Japan opened. It maybe that a large amount of magmatic activity was associated with the opening of the Sea of Japan at about 20 Ma in the region of the Sea of Japan, Oki, Tsushima and Goto.
Magmatic activity in the Goto and Koshikijima region occurred up to 8-7 Ma, the latest Miocene, which is the same time when magmatic activity in the older Okinawa Trough started. If the Goto region was located in the extensional area from the Okinawa Trough, it is possible that magmatic activity related to the older Okinawa Trough also occurred in Goto and Koshikijima.
It has previously been proposed that the Amakusa area belongs to the Inner zone of Kyushu, but the granitoid rock series and the existence of high Mg andesite in the Amakusa area is similar to that found in the northern Outer zone or Setouchi volcanic zone. The Amakusa area clearly needs a more detailed study.

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Based on the newly determined double-beta-decay half life of ¹³⁰Te ((7.0 ± 0.9_stat ± 1.1_syst) ×10²⁰ yr: Arnold et al., 2011), we have measured the direct mineralization ages on tellurium-bearing minerals from some hydrothermal gold deposits by the ¹³⁰Te-¹³⁰Xe* method. The results are as follows: Calaverite (21.9±2.3 Ma) from the epithermal Au-Te vein, Cripple Creek mining district, USA; Hessite-petzite (34.9±5.4 Ma) from the epithermal Au-Te vein, Cash mine, Boulder County, Colorado, USA; Altaite (1,040±80 Ma) from the Au-Te quartz-carbonate vein of the Mattagami Lake mine, Matagami, Quebec, Canada; Tellurobismuthite-tetradymite (9.4±1.2 Ma) from Bi-Te quartz vein, Tsushima Island, Nagasaki Prefecture, Japan; Tellurobismuthite (81.4±2.6 Ma) from hydrothermal Au-Te vein, Oya mine, Miyagi Prefecture, Japan;　Tellurobismuthite (85±18 Ma ) from the Au-Te quartz vein, Suwa mine, Ibaraki Prefecture, Japan. These ages are obviously younger than previously reported mineralization ages by K-Ar, Ar-Ar or Pb-Pb methods.

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