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
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.
科学领域:
- 地质地质地质地质地质地
- 地质年代学地质年代学.
- 火山学 火山学是一门学科.
背景情况:
- 黑山地区有着已知的火山活动历史.
- 之前的研究还没有确定该地区火山岩的年龄.
研究的目的:
- 为了确定北方黑山山脉里约石期火山岩的年龄.
- 了解火山活动与区域升级之间的关系.
主要方法:
- -同位素测年法被用来确定火山岩的年龄.
主要成果:
- 黑山北部的石火山岩产生了10.5 +/- 1.5百万年的-同位素年龄.
- 这个年龄比该地区之前报告的火山活动要小得多.
结论:
- 在奥利古森时代之后,黑山的重新升起伴随着火山活动.
- 这一发现扩大了黑山火山事件的已知时间框架.
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