Crystalline schists in the district consist of sandstone-schists, black-schists of pelitic origin, green-schists of basic tuff and lava origin, and quartz-schists of chert origin., The formation of crystalline schists in the district is tabulated in the descending order as follows : Minawa formation comprises four beds of green-schists anb two beds of sandstone-schists; the other members are pinkish quartz -schists, and black-schists 1000∼300Om., Koboke formation is mainly sandstone-schists inter-bedded with black-schists and green-schists 300∼50Om., Kawaguchi formation is mainly composed of black-schists, interbedded with green-schists 100∼200m., Oboke formation almost exclusively consists of sandstone-schists 30∼50m., The ore-deposit of the Shingu Mine lies in the lowermost, non-spotted green-schists of Minawa formation., The ore-deposit is a "Kieslager" in type, having a pole-like form., The foot-wall of the ore body is green-schists, characterized by the presence of quartz, carbonate and hematite, and the hanging-wall is massive green-schists, characterized by the abundance of epidote, and parallel seams or veinlets of hamatite-quartz, chlorite, stilpnomelane, magnetite., In the green-schists near the contact with ore bodies are impregnated granules or pyrite and chalcopyrite, forming sinuated seams., The axis of sinuation coincides with that of the lineation of green-schists.,

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In the central and northern parts of Oita prefecture, Kyushu, younger Cenozoic rocks are exposed extensively., They rest mainly on a basement of Paleozoic strata, and granites of the Ryoke type and partly on metamorphic rocks of Sambagawa type and the Cretaceous Onogawa group., They are composed of volcanic, pyroclastic and sedimentary rocks., From fossil and other evidence, they are dated as Miocene to recent., They represent a complicated history of volcanic activity and sedimentation, both of which are closely related., The history comprises four major geologic cycles, each of which is distinguished by the following criteria:(1) In volcanic cycles, (a) changes in rock types and modes of activity (flow type or explosive type) and (b) changes in dimension and in geographical position of activity., (2) In sedimentary cycles, (a) lateral and vertical changes in sedimentary facies, that strongly reflect the formation of basins by tectonic movements; (b) changes in dimension and in the geographical position of the basins., On the basis of these cyclic records, the younger Cenozoic rocks are grouped into four stratigraphic units; the Usa (F in age), the Sekinan (G-H), the Oita (I) and Kuju (J-K) groups in ascending order., The 2nd and the 4th groups correspond to the Setouchi and the Sanin volcanic series respectively, so far as the volcanism is concerned., As the volcanic series corresponding to the 1st and the 3rd groups has been neglected heretofore, it should be sought more extensively in Southwest Japan or elsewhese., This paper offers some evidence concerning the origin of the Oita-Kumamoto line, one of the major tectonic lines in Kyushu.,

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Von 1937 an haben wir stratigraphische Untersuchungen uber das Palaeozoikum des Setamai-Gelandes im Kitakami Gebirge, nordostliches Honshu, Japan, ausgefuhrt., Die dortige geologische Kartierung (MaBstab 1/5000) fur die karbonische Formation ist jetzt beinahe vollendet., Das Karbon wird in diesent Gelande von unten lithologisch geteilt in -III, -II, -I, I, II, III, IV, V, VI und VII Gruppe., Darunter bestehen die Gruppen -I, II und IV ausschlieBlich aus Schalstein; VI und VII hauptsachlich aus Kalk und die anderen nus Tonschiefer, Sandstein, Schalstein und unreiner Kalkschicht., Zwischen der Gruppe VI und V ist eine Diskordanz vorhanden, und die stratigraphische Beziehung der Gruppe VI und VII ist wahrscheinlich auch diskordierend, obwohl dies bis jetzt noch nicht vollkommen nachgewiesen ist, Andere Gruppen sind einander ubergelagert ohne stratigraphische Lucke., Alle diese Gruppen sind auch palaeontologisch unters cht worden (siehe Tab., 2, 3, 4 und Literaturverzeichnis), und die Biozonen der meisten Spezies sind bestimmt., (Siehe Fig., 3)., Aus diesem Grunde mochten wir die karbonische Formation des Setamai Gelandes von untea in eine Hikoroiti-Serie, Arisu-Serie, Ohdaira-Serie, Onimaru-Sarie und Nagaiwa-Serie teilen., Die Arisu-Serie und Ohdaira-Serie sind auch wieder geteilt in eine Hinozuti-Stufe, Jumonji-Stufe Maide-Stufe und Kozubo-Stufe., Hinsichtlich des Fossilieninhaltes sind Hikoroiti mit Etroeungt, Arisu mit Tournai, Ohdaira mit Unter-Vise und Onimaru mit Ober-Vise beinahe vergleichbar., Die Nagaiwa-Serie laBt sich vielleicht mit der Fusulinella-Zone des pensylvanischen Systems parallellisieren., Palaeozoogeographisch stand das Geosynklinalmeer des Kitakami-Gebirges, von der Hikoroiti-zur Ohdaira-Zeit, in enger Beziehung zur Geosynklinale des westl chen Australien., In der Onimaru-Zeit aber zeigt das Geosynklinalmeer des Kitakami-Gebirges isotopische Beziehung mit dem Kueichouphyllum Meer Sudchinas., In der mittleren karbonischen Zeit liegt das Kitakami-Gebirge wahrscheinlich unter demselben Meere mit dem Penchi-Becken, Mandschurei, nordostliches China.,

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