一个伟大的晚期埃迪亚卡拉冰河时代
Ruimin Wang1, Bing Shen1, Xianguo Lang2
1Key Laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education and School of Earth and Space Sciences, Peking University, Beijing100871, China.
National science review
|June 30, 2023
概括
埃迪亚卡拉生物群的生物群.
科学领域:
- 古气候学 古气候学
- 古生物学的古生物学
- 地质时间学 (Geochronology)
背景情况:
- 埃迪亚卡拉生物群在加斯基尔斯冰期之后出现,这表明它与动物进化有联系.
- 由于冰川沉积物的年龄限制有限,埃迪亚卡拉冰川形成的时间不确定.
- 埃迪亚卡冰川的全球分布与低度的雪球地球条件相矛盾.
研究的目的:
- 解决埃迪亚卡拉冰川的时间和性质.
- 为了研究冰川和埃迪亚卡拉生物群进化的关系.
- 为了使全球冰川沉积物的发生与古磁性和古地理数据相协调.
主要方法:
- 在塔里姆的Hankalchough冰川沉积物相对于舒拉姆碳同位素游览的约会.
- 对古磁数据的分析表明了显著的真正极地漫游.
- 古地理重建包括真正的极地流浪和非雪球条件.
主要成果:
- 在舒拉姆碳同位素游览后 (约. 571-562万年) 的时间.
- 真正的极地流浪重新定位了大陆,促进了极地温带度的冰川.
- "伟大的埃迪亚卡拉冰川"是从大约开始的双时和连续的. 580-560万年前的时间.
结论:
- 埃迪亚卡拉冰川发生在移徙大陆的双重时间内,而不是作为一个全球性的雪球事件.
- 冰川-降冰时期的动态很可能影响了埃迪亚卡拉生物群的辐射,周转和灭绝.
- 这项研究为了解气候变化背景下的早期动物进化提供了一个新的框架.
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