概括
位于阿拉斯加的白时期的土岩表明,它沉积在一个古老的海洋沟中. 这个地质特征后来被现代的阿列乌提亚弧系统所取代.
科学领域:
- 地质地质地质地质地质地
- 古生物学的古生物学
- 构造学 构造学 构造学 构造学
背景情况:
- 在阿拉斯加大陆边缘和贝林架边缘沿着白纪的土石暴露.
- 这些沉积物延伸1700公里,表明具有重要的地质特征.
研究的目的:
- 为了解释在阿拉斯加的白纪流石的沉积环境.
- 为了理解从白纪沟到三级阿列乌提亚弧沟的构造过渡.
主要方法:
- 对沿着大陆边缘的化物暴露的分析.
- 考察古流动流动模式的研究.
- 识别和分析火山碎片组成.
主要成果:
- 矿沉积发生在海洋沟环境中.
- 古流动数据表明,与大陆边缘平行流动.
- 丰富的石岩火山碎片指出了火山的来源.
结论:
- 阿拉斯加的白纪大陆边缘与海洋沟接壤.
- 这条沟随后在第三纪早期被阿列乌提亚弧系统所取代.
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