在南达科他州北方黑山区的晚三级火山活动的证据,南达科他州

Science (New York, N.Y.)
|May 27, 1977
PubMed
概括

黑山区的石期火山岩可追溯到1050万年前. 这一发现揭示了火山活动与奥利古纪时代后该地区重新升起的同时发生.

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