glaciations

glaciations的基本解释

n.

冻结成冰, 冰河作用( glaciation的名词复数 )

与glaciations相关的网络例句 [注：此内容来源于网络，仅供参考]

There were five Quaternary glaciations in the Halasi River Catchment according to the remains of Quaternary glaciations and C〓 dating.

根据第四纪冰川遗迹和〓测年，哈纳斯河流域存在五次明显的冰期，其中更新世存在三次冰期。

5Ma. 2 No remnants of glaciations are found on the soil sites of Mount Harding, which suggests that the Antarctic glaciations have not reached the soil sites since at least 0.5Ma, and the ice cap was not much higher than present, even during the Last Glacial Maximum.

水分高，Na〓含量高；无水分，Mg〓含量高，Na〓的含量则很低；K〓和Ca〓的含量与土壤的水分关系不大，在土壤剖面中分布稳定，变化趋势不明显。

Several main results on the evolutions of the life and environment on early earth are summarized as follows:(1) the oxygenation of surface environment didn''t cease until a stable stage for 0.4Ga appeared after 1.6Ga;(2) compared to the isotopic compositions of kerogens and coexisted carbonates, the differences between two can effectively carrier the signals from local environments and bio-assemblages;(3) multiple isotopic relationships between kerogens and individual alkanes in Proterozoic samples were observed, which would depend on the specific biogeochemical processes;(4) repeated biogeochemical changes were observed accompanying Neoproerozoic glaciations, which suggesting that environmental rather than evolutionary forces were driving the biogeochemical changes;(5) the bio-radiations after Neoproterozoic glaciations were definitely suggested by molecular and isotopic data to be at the early Cambrian and after the middle of Doushantuo deposition with different triggers for them.

研究获得以下重要认识：（1）古元古代地表环境的氧化可能一直持续到中元古代早期(约1.6Ga)，而在此之后的4亿年里则保持相对稳定；（2）相对于传统的干酪根和碳酸盐的碳同位素组成，二者之差则能更好反映区域环境的演化特征；（3）在元古代干酪根与单体烷烃类之间存在多种碳同位素组成关系；而其与不同的生物地球化学过程有关；（4）全球海洋生物地球化学特征随新元古代多次冰期出现循环波动，这显然为环境因子的驱动；（5）在新元古代大冰期之后，分子与同位素数据显示地球生命在陡山沱中后期和早前寒武纪出现两次大辐射，然而两次生命辐射的本质却是不同的。