Portlandian Stage

the upper stage of the Jurassic system. It was identified in 1842 by the French geologist A. d’Órbigny on the Isle of Portland, a peninsula in southern Great Britain. In its stratotype it is represented by shallow-water marine deposits—clays, glauconitic sands, and sandstones in the lower strata and limestones in the upper. In the Mediterranean region, the Crimea, and the Caucasus the Portlandian stage is referred to as the Tithonian stage; on the East European Platform the deposits of the Volga stage correspond to the Portlandian stage.

单词	portlandian stage
释义	Portlandian Stage Portlandian Stage the upper stage of the Jurassic system. It was identified in 1842 by the French geologist A. d’Órbigny on the Isle of Portland, a peninsula in southern Great Britain. In its stratotype it is represented by shallow-water marine deposits—clays, glauconitic sands, and sandstones in the lower strata and limestones in the upper. In the Mediterranean region, the Crimea, and the Caucasus the Portlandian stage is referred to as the Tithonian stage; on the East European Platform the deposits of the Volga stage correspond to the Portlandian stage.
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