词条 | Waucoban Series |
释义 | Waucoban Series geology lowermost Cambrian rocks (the Cambrian Period lasted from 542 million to 488 million years ago); the name is derived from exposures found at Waucoba Springs, Calif. The period of time corresponding to the rocks of the Waucoban Series is known as the Waucoban Epoch. The Waucoban is characterized by a distinct faunal assemblage, especially typified by the trilobite genus Olenellus. As yet, no clear-cut, universally applicable definition that would demarcate the base of the lowermost Cambrian strata has been agreed upon. |
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