美国西部正在演变的俯冲区,根据火性岩石的解释
概括
安德西特岩石化学表明,在早期和中期的代,在美国西部下面有两个不同的俯冲区. 中生时代的沉降沿着一个单一的,更的区域发生,揭示了构造历史.
科学领域:
- 地质地质地质地质地质地
- 构造学 构造学 构造学 构造学
- 石化学 石化学是一门学科.
背景情况:
- 俯冲过程显著塑造了大陆边缘.
- 了解过去的俯冲动态对于解释构造进化至关重要.
- 岩石岩石作为岩和构造活动的关键指标.
研究的目的:
- 为了研究美国西部下方的浮沉区域的几何和时间.
- 使用地质化学代理来区分中生代和生代的降温事件.
主要方法:
- 在石岩中分析K(2) O与SiO(2) 的比率.
- 解释地质化学数据以推断潜水区特征.
主要成果:
- 早期和中期的代潜水发生在两个亚平行杂交区沿线,向东倾斜约20度.
- 西部潜水带位于大陆边缘,而东部区域更深,位于大陆板下面.
- 预计中生代的降温沿着一个单一的,更的降温区域发生.
结论:
- 石岩中的地化学变异为不同的古新生代和中新生代潜水结构提供了强有力的证据.
- 已识别的俯冲区为美国西部板块构造史提供了洞察力.
- 这项研究完善了向西俯冲潜水的模型及其对大陆地演变的影响.
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