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The term South German Jurassic ((ドイツ語:Süddeutscher Jura)) in earth history is used to refer to a lithostratigraphic rock unit at the hierarchical level of a super group. The rocks of the South German Jurassic were mainly deposited during the Jurassic period about 199 to 146 million years ago. The boundaries of the South German Jurassic and those of the chronostratigraphic or international Jurassic are not, however, exactly coincident. The depositions began rather later than the date of the international Triassic/Jurassic boundary and end as a result of erosion of the uppermost strata at various times during the Upper Jurassic, i.e. well before the international Jurassic/Cretaceous boundary. The rock unit of the South German Jurassic is underlain by Keuper; in between is a small stratigraphic hiatus. Above the South German Jurassic the beds follow discordantly and with a large stratigraphic gap; in addition, Regensburg Green Sandstone occurs very locally, which is dated to the Cenomanian stage of the Cretaceous period. In its southern fringes the South German Jurassic dives under the Palaeogene Molasse depositions of the basement. == Divisions == The main divisions of the South German Jurassic are the: * Black Jurassic - 199 to 175 million years ago * Brown Jurassic - 175 to 161 million years ago * White Jurassic -161 to 150 million years ago 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「South German Jurassic」の詳細全文を読む スポンサード リンク
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