概括
普莱斯托纪时期的时代.
科学领域:
- 地质地质地质地质地质地
- 古气候学 古气候学
- 在平流体学上,平流体学是平流体学.
背景情况:
- 普莱斯托时代的生物层状图边界仍在争论中,可能与冰河期的开始不一致.
- 以前定义地质边界的方法在与气候事件同步方面存在局限性.
研究的目的:
- 为了确定一个可靠的岩石地层学和地质气候边界的普莱斯托纪的基础.
- 为了将这条边界与大陆冰期的开始联系起来.
主要方法:
- 使用电子显微镜分析沙粒表面质感.
- 对冰川活动指标的沙粒表面纹理进行了检查.
主要成果:
- 确定了明显的沙粒表面纹理,表明冰川过程.
- 这种纹理提供了一个广泛适用的边界标记.
结论:
- 对沙粒的电子显微镜分析提供了一种可靠的方法来确定普莱斯托时代的基础.
- 这一边界与大规模冰山分娩的开始相关,标志着大陆冰川的开始.
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