概括
德拉华河谷的洪水平原沉积物在6000多年里通过上岸沉积不断积累. 这个缓慢的,不间断的过程,是由河流驱动的.
科学领域:
- 地质地质地质地质地质地
- 沉积物学的沉积物学
- 四分学科学 四分学科学
背景情况:
- 洪水平原是由河流过程塑造的动态景观.
- 了解沉积物的积累对于重建河流历史和预测未来变化至关重要.
研究的目的:
- 为了分析特拉华河洪水平原的沉积历史.
- 为了确定负责洪水平原建设的占主导地位的地形过程.
主要方法:
- 洪水平原沉积物的沉积物学分析.
- 放射性碳测年法,以建立一个时间框架.
主要成果:
- 一个厚厚的,不间断的序列的上岸泛滥平原沉积物被确定.
- 没有发现点条沉积或显著侵蚀的证据.
- 沉积起始于至少6000年前,并持续到现在.
结论:
- 越岸沉积是特拉华河谷洪水平原建设的主要机制.
- 河流缓慢的横向迁移率有利于持续的上岸积累,而不是道移动和侵蚀.
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