In the central part of the Miura Peninsula, the Hayama group, which uncomformably underlies the Miura group, is distributed in two areas, namely, the Akiya-Takeyama area and the Hayama-Kinugasa area., In the Akiya-Takeyama area, the group is divided into the following seven formations in discending order (3), (3') and (3") are the same horizon., (5) Kinugasa mudstone, (1700m+in thickness)., (4) Nakayama fine sandstone, (1100m±in thickness)., (3) Oyama tuffaceous sandstone, (1100m±in thickness); (3') Osawa sandston and conglomerate, (900m±); (3") Sakanodai tuff-breccia, (400m±in thickness)., (2) Hatadateyama alternation of sandstone and shale, (1000m± in thickness)., (1) Morito mudstone, (1400m+in thickness)., These formations are folded, and several masses of serpentine have been intruded along the three axes of the folds., In the Hayama-Kinugasa area, the group is divided into the following two formations in discending order., (2) Tateisi shale, (350m+in thickness)., (1) Takeyama siltstone, (1500m+in thickness)., These formations are monoclinic in structure, strike east, and dip about 60° north., Although no important fossils have been discovered in these formations, on the basis of stratigraphy, the group is thought to be Japanese lower Miocene (F₁ in IKEBE'S Letter Nomination) in age., My paper on the Miura group will be published in this Journal in the near future.,

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The Shimozaisho alternation of limestones and clayslates is an unusual sedimentary mass located within the Hida gneiss terrain., The alternation is covered by later sediments and lavas; however, its relation to the Hida gneiss is indeterminable., Although the alternation of limestones and clayslates is both thermally and dynamically metamorphosed, some poorly preserved fossil corals and fusulines have been found in the Shimozaisho limestone, a member of the alternation., These fossils suggest Moscovian for the age of the limestone., The find of the Moscovian Fusulina Zone is a new discovery in the strata of the Hida Plateau., Because the Jurasso-Cretaceous Tetori group which overlies the Shimozaisho alternation is not metamorphosed, the alternation is thought to have been metamorphosed sometime between the late Paleozoic and early Mesozoic.,

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日本の第三紀砂鐵層及びそれに伴う凝灰岩中には, 色々の見掛けを有する緑色鑛物が見出される., その中で最も廣く分布する1緑色鑛物を, 筆者は1941年に詳細に研究した詰果, この鑛物は, 主として, 化學成分の上から, 古く(1887年)H. LEMBERGにより輝石の變成物質として記載された物質の中の1つに極めて近いことを見出し"lembergite"と名付け, X線的研究の結果より, この鑛物は, モンモリロナイトに屬する鑛物であろうと結論した., 最近(1948年)に筆者は, 宮城縣名取郡生出村茂庭の砂鐵層に伴う緑色礫灰岩中より既に分離したlemergiteの試料(1941年に使用したもの)より, 純粹に緑色鑛物のみを集めることに成功し, その性質を調べたところ, 豫想通りモンモリロナイト群に屬する鑛物であつて, しかも鐵の極めて多いsaponiteに一致することを見出した., その性質は次の通りである., 屈析率1.,56～1.,58; 複屈析0.,02～0.,03; 多色性, X: 緑色～帶緑褐色, Z: 帶緑褐～暗褐; SiO₂, 39.,68%; Al₂O₃, 3.,93%; Fe₂O₃, 19.,82%; FeO, 1.,12%; MgO, 11.,21%; CaO, 2.,37%; TiO₂, 0.,37%; MnO, 0.,19%; H₂O (+), 6.,16%; H₂O (-), 15.,11%; 計99.,66%., 同一試料であるにかかわらず, Fe₂O₃/FeOの比は, 1941年に, 3.,40, 1948年に7.,95に増している., よつて, 第一鐵の2次的の酸化が著しいと見て, 第二鐵の全量を第一鐵に換算して構造式を導いてみると, (Al_0.,04Fe_1.,45Mg_1.,52)(Si_3.,62Al_0.,38)O₁₀(OH)₂(Ca/2)_0.,46となり, saponiteのマグネシウムのほぼ半分を第一鐵で置換したもの, 即ち鐵の多いsaponiteに相當する., エチレングリコルで15.,7±0.,3kXの粒末線は16.,9kXに移る., いわゆる緑色凝灰岩中には緑泥石, セラドナイトなどと共にsaponiteもまた廣く存在する可能性がある.,

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This paper discusses the following subjects concerning the Kumano group (Miocene, = Miyai series + Shimosato series + unnamed strata) in the vicinity of the Kumano coal field., (1) The Kumano group is divided into two formations, namely the Koguchi and Mitsuno formations, the former being characterized by a large quantity of siltstone and the latter by coarse quartzose sandstone; the group is further subdivided as follows., Hyoren member, (ss & st) 0yama member, (ss & st alt) Kowase member, (ss) Akagi member, (ss & st) Shiko member, (ss) Taniguchi member, (ss & st alt) Miyai coal-bearing member Wada member, (st) Taniguchi member, (ss & st alt) Wadagawa member, (st) Kamazuka member, (ss & st alt) Shikiya member, (st) Ohara member, (eg & ss) Mitsuno formation Koguchi formation Kumano group Kinan "group" (2) The strata of the Kumano group in this district have a general strike of north-south or N 20° and dip 15° to 40° east, except along the syncline in the northeastern part of the district., Many faults are present in the northern part but there are fewer to the south., The writers think that these structures had been made before the intrusions of the Kumano acidic igneous rocks., (3) The rock facies and the molluscan fossil-coenoses of the group suggest that the basin of deposition became smaller as a whole, especially after the deposition of the Koguchi formation, and accompanying the depoaition of coal., (4) From the field observations, the writers consider the so-called Eocene Shimosato series located on the southern coastal area as being the same age as the so-called Miyai series, though both are very different from each other in rock-facies and structure., However, the process which caused the differences remains unknown.,

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