WEKO3
-
RootNode
アイテム
東北地方における第三紀造山運動について : 奥羽脊梁山脈を中心として
http://hdl.handle.net/10097/33138
http://hdl.handle.net/10097/3313809dc9e1f-e329-4a01-bfe8-4201eb2caadd
| 名前 / ファイル | ライセンス | アクション |
|---|---|---|
KJ00004219792.pdf (7.0 MB)
|
|
| Item type | 紀要論文 / Departmental Bulletin Paper(1) | |||||||
|---|---|---|---|---|---|---|---|---|
| 公開日 | 2008-05-02 | |||||||
| タイトル | ||||||||
| タイトル | 東北地方における第三紀造山運動について : 奥羽脊梁山脈を中心として | |||||||
| 言語 | ||||||||
| 言語 | jpn | |||||||
| 資源タイプ | ||||||||
| 資源タイプ識別子 | http://purl.org/coar/resource_type/c_6501 | |||||||
| 資源タイプ | departmental bulletin paper | |||||||
| 著者 |
北村, 信
× 北村, 信
|
|||||||
| 著者(ヨミ) | ||||||||
| 識別子Scheme | WEKO | |||||||
| 識別子 | 30642 | |||||||
| 姓名 | Kitamura, Nobu | |||||||
| 抄録 | ||||||||
| 内容記述タイプ | Abstract | |||||||
| 内容記述 | To clarify the orogenic evolution of the Backbone Ranges in Northeast Honshu, Japan, the writer described the stratigraphy and geological structure of the Neogene strata developed in the area bordering Iwate, Akita, Miyagi and Yamagata Prefectures. The Neogene sediments in this area are in general separated from the basement complex of Waagenophyllum-bearing Permian sediments and granodiorite by distinct angular unconformity, and consists largely of the marine early and middle Miocene sediments and the terrestrial late Miocene and early Pliocene sediments. The stratigraphical sequence of the strata of this area is given in Fig. 1. The stratigraphical sequence and geological structure of the strata developed in the central parts of Northeast Honshu, which includes the Iwate and Akita, the northern parts of Miyagi and Yamagata, and the southern part of Aomori Prefectures which have similar historical evolution, are divided into four sedimentary provinces, viz., from east to west, the Catchment Area of the Kitakami River, the Backbone Ranges, the Inter-mountain Basins and the Japan Sea Coast. The stratigraphical relationships and geological growth of each provinces are discussed and accompanied with Palaeogeographic Maps (Figs. 10-15), and inter-provincial correlations are shown in Table 10. For convience of illustrating the successive evolutional change of this provinces, the writer divided the Neogene sediments into several stages. (Fig. 10). Stage I and the lower half of stage II may correspond to the early Miocene, the upper half of stage II to and including stage IV may be middle Miocene, stage V is regarded as late Miocene and stages VI and VII are thought to be Pliocene, in their respective ages. The lower part of the Neogene deposits are characterized by intense volcanism, the product of which are either formed on the floor of a narrow geosynclinal zones of subsidence, such as the Backbone Ranges, or on the backland and foreland areas. The first volcanism on the floor of this geosynclinal zones are mostly of basic lava and its pyroclastics, and these are altered to propyrite and the so-called propyritic lithoidal tuff breccia affected by hydrothermal alteration of later stages. The deposits representing stage I correspond to those mentioned above. When the rate of supply of the products of this vlocanism is small compared with the rate of subsidence, fine clastic materials such as clay and silt may deposit in such narrow geosynclinal troughs (Figs. 10, 17). The lower half of the Oishi Formation and its correlatives in the Backbone Ranges which predominate in black siltstone rather than green tuffs were formed under the same condition just stated. This corresponds to the lower half of stage II, a time when the foreland area of the Intermountain Basins and the Japan Sea Coast were not yet subjected to this marine invasion. Following these subsidence in the Backbone Ranges, another intese activity which caused the effusion of rhyloitic-andesitic lava and its pyroclastices occurred during the time when the marine transgression progressed to the western foreland area. Thus, the upper half of the Oishi Formation and its correlatives, which comprise "green tuffs", consisting of rhyolitic-andesitic lava, agglomerate, and fossiliferous fine grained sediments as sandstone or black siltstone, were formed. This corresponds to the upper half of Stage II and is characterized by the Miogypsina-Operculina fauna and the "Sugota-Nishikurosawa fauna". Weakening of these volcanisms in the Backbone Ranges and progression of the marine transgression especially in the western part where the maximum subsiding zones were shifted westwards from the east, fine grained sediments of stage III, such as siliceous shale besides conglomerate with angular blocks of andesite and tuffs were deposited. The Onnagawa Formation with a maximum thickness of more than 1, 000 meters in the Yokote Basin, near the Dewa Hillyland, rapidly lessens in thickness both eastwards and westwards, thus demonstrating that the maximum subsiding zones of the geosyncline shifted from the east to occupy a position around the Dewa Hillyland during stage III. Subsequently a marine regression took place around the Backbone Ranges, owing to the uplift of the geanticlinal zone accompanying acidic extrusions. Accordingly, the geosynclinal basin of this area became more differentiated. From the 1, 800 meters thick Funakawa Formation along the eastern borderland of the Shonai Basin, Yamagata Prefecture, it is evident that the maximum subsiding zone of the geosyncline had shifted farther westwards during stage III. The eastern part of the Backbone Ranges remained as a back-deep of this geosyncline, where coarse to fine arenaceous sediments intercalating black siltstone were deposited ; Yamatsuda and Orose Formations are representative. Towards the end of this stage, the backdeep of the eastern region was filling up by rapid aacumulation of pyroclastic deposits, such as represented by the Ichinonohara Tuff Member. This corresponds to Stage V. When the sea had completely withdrawn form the Backbone Ranges and the Catchment Area of the Kitakami River, the sediments of stage V commenced deposition around the Backbone Ranges, and the more eastern areas were exposed above sea level. Thus, the geanticlinal ridges which is considered as a causes of the major faults and foldings on both sides of the Backbone Ranges was formed in this area. In the western border of the Inter-mountain Basins, the southern part of the Dewa Hillyland was slowly uplifted without accompanying volcanic extrusions. The unconformities between stages V and VI were subjected to the changes of the depositional basins and environment since these geanticlinal upward movement occurred. In stage VI, the shallow sea in which the Kitaura Formation and its marine equivalents were formed was shifted farther westwards than during Stage V, through the same process as during stages III, IV, V. The sediments of the eastern land area consists largely of dacite and its tuffs with subordinate freshwater sediments, such as quartzose sandstone, tuffaceous sandstone and incoherent tuffaceous shale besides thin coal seams, which were deposited in the subsiding lowalnd area casued by igneous eruptions. In the Shinjo Basin, a marine embayment still persisted and was connected to the western seas through the northwestern part of this basin. The sediments are composed of tuffaceous sandstone, tuffaceous siltstone and tuff, containing many shallow water molluscs, besides thin coal seams at its marginal parts. The sediments represented by the Kitaura, Tentokuji and Sasaoka Formation in the Japan Sea Coast are composed of gray siltstone, sandstone and tuffaceous sandstone and their alternation. In the Pliocene, the western maine area was shifted farther westwards with the gradual uplift of the Dewa Hillyland with the character of non-volcanic geanticline. Thereby the inland sea in the Shinjo Basin became isolated from the sea, and gradually changed into a coastal marshy land where the lignite-bearing Shinjo Group was deposited. It is clear that the parallel geanticlinal and narrow subsiding zones of sedimentation in this geosyncline were shifted from the east westwards during the course of orogenic evolution. Successive evolutional changes of this geosyncline are illustrated in a series of Paleogeographic Maps (Figs. 17-22) and schematically presented in Fig. 23. | |||||||
| 書誌情報 |
東北大學理學部地質學古生物學教室研究邦文報告 巻 49, p. 1-98, 発行日 1959-03-02 |
|||||||
| ISSN | ||||||||
| 収録物識別子タイプ | ISSN | |||||||
| 収録物識別子 | 00824658 | |||||||
| 書誌レコードID | ||||||||
| 収録物識別子タイプ | NCID | |||||||
| 収録物識別子 | AN00171452 | |||||||
| フォーマット | ||||||||
| 内容記述タイプ | Other | |||||||
| 内容記述 | application/pdf | |||||||
| 著者版フラグ | ||||||||
| 出版タイプ | VoR | |||||||
| 出版タイプResource | http://purl.org/coar/version/c_970fb48d4fbd8a85 | |||||||
| その他の言語のタイトル | ||||||||
| その他のタイトル | Tertiary Orogenesis in Northeast Honshu, Japan | |||||||
| 出版者 | ||||||||
| 出版者 | 東北大學 | |||||||
| 資源タイプ | ||||||||
| 内容記述タイプ | Other | |||||||
| 内容記述 | 紀要類(bulletin) | |||||||
| 登録日 | ||||||||
| 日付 | 2008-05-02 | |||||||
| 日付タイプ | Created | |||||||
| 公開日（投稿完了日） | ||||||||
| 日付 | 2008-05-02 | |||||||
| 日付タイプ | Created | |||||||
| 発行日 | ||||||||
| 日付 | 1959-03-02 | |||||||
| 日付タイプ | Created | |||||||
| フォーマット | ||||||||
| 内容記述タイプ | Other | |||||||
| 内容記述 | 6969572 bytes | |||||||
| 更新日 | ||||||||
| 日付 | 2010-01-27 | |||||||
| 日付タイプ | Created | |||||||
