二畳系舞鶴層群, その層序と古生代末造山運動に伴なう動物化石群の変遷

京都大学0048新制・課程博士理学博士理博第42号新制||理||18(附属図書館)252京都大学大学院理学研究科地質学鉱物学専攻(主査)教授 松下 進, 教授 吉沢 甫, 教授 松下 久道学位規則第5条第1項該当Kyoto UniversityDA

Preliminary Report on the Permo-Trias of Kashmir

A team of Japanese and Indian Geologists carried out detailed studies of the Permo-Triassic sections in the Srinagar region, Kashmir, during 1969. This report embodies certain conclusions arrived at in the light of these studies. The section at Guryul Ravine is described in detail, being the best in the Srinagar region. Lithological and faunistic comparisons with other areas examined are also referred to. The different faunistic zones of the Lower Trias of this area are compared with other important extra-Indian occurrences. The Zewan Series (Permian) at Guryul Ravine is succeeded by Lower Triassic beds. The arenaceous sediments pass into calcareous through argillaceous sediments. There is neither an intraformational nor interformational unconformity indicative of a hiatus in deposition. Many characteristic Permian elements survived in the lower part of the Lower Trias, constituting a zone of mixed fauna of Permo-Trias. This suggests a rapid faunal change from Permian to Lower Trias but not discontinuous. The lithology however supports a gradual change from Palaeozoic to Mesozoic. The advent of Lower Trias is marked by the appearance of characteristic species like Claraia stachei (BITTNER), SPATH in the dark shales. The paper also records a number of important Lower Triassic ammonoids (Otoceras, Glyptophiceras, etc.), which were so far not known from the Srinagar region. Considering the evolutionary position of some of the species of Otoceras, the boundary between the Permian and Trias is tentatively placed just below the advent of Claraia stachei

The Permian and the Lower Triassic Systems in Abadeh Region, Central Iran

The continuous sequence of the Permian and the Lower Triassic Systems was fully examined paleontologically and sedimentologically in Abadeh region, Cenral Iran. Based on the correlation of the Permian in the Tethys province by means of fusulinid, ammonoid and conodont zonations together with brachiopod, coral and bryozoan fossils, it is concluded that the Upper Permian is reasonably classified into three stages, the Abadehian, the Dzhulfian, and the Dorashamian. Biostratigraphical and sedimentological study indicates a paraconformable relation between the Permian and Triassic, and the equivalent of the lower half of the Otoceras woodwardi zone is missing as judged from the conodont zones. The Dorashamian is older than the Griesbachian or Gangetian, and not the equivalent of the latter. The faunal change is related to not only local environmental change but universal causes. A remarkable attrition of species began in the Dzhulfian and reached a climax at the end of the Permian. Almost all the species had disappeared by the end of the Permian corresponding to the progressive shallowing and retreat of the sea. Rapid transgression and incoming of new organisms at the beginning of the Triassic is evident in the lithofacies and biofacies of the Lower Triassic