概括
在克什米尔发现了米纪和下三叠纪的动物元素,这表明米纪-三叠纪边界的生存. 这一发现支持了先前在巴基斯坦发现类似的混合动物群的发现.
科学领域:
- 古生物学的古生物学
- 在平流图学中,平流图学.
- 生物分层学是生物分层学.
背景情况:
- 珀米亚-特里亚斯纪的边界标志着地球历史上一个重要的灭绝事件.
- 了解跨越这个边界的动物生存对于重建过去的生态系统至关重要.
- 之前的研究已经确定了巴基斯坦最低的三叠纪层中的混合动物协会.
研究的目的:
- 记录和解释在克什米尔发现的混合动物协会.
- 为了调查珀米亚纪动物元素在底纪的存活情况.
- 将克什米尔的发现与西巴基斯坦的类似事件进行比较.
主要方法:
- 在克什米尔的Guryul Ravine,大约15英尺的岩层的层级分析分析.
- 化石动物群的识别和记录,包括生产的足动物 (例如,Spinomarginifera) 和长足动物 (例如,Claraia).
- 动物组合与已知的三叠纪下期和波斯纪动物群的比较.
主要成果:
- 发现与克拉拉亚相关的多样化的生产型手足类动物群,包括Spinomarginifera.
- 这些化石发生在斯基特 (下三叠纪) 层中.
- 动物组合代表了幸存的珀米亚和下纪元素的真正协会.
结论:
- 格鲁尔峡谷的动物群提供了证据,证明了某些珀米亚时代的足足类动物在低三叠纪时期的生存.
- 这些发现证实了西巴基斯坦盐山脉和Surghar山脉中存在类似的混合动物协会.
- 这项研究强调了一些珀米亚时期的生命形式在关键的珀米亚-三叠纪过渡期间的持久性.
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