Abstract—

All current data on the Jurassic and Cretaceous climates of Siberia based on isotope, paleontological, and lithological proxies are summarized. The late Pliensbachian cooling episode, early Toarcian warming, promptly replaced by long-term Middle Jurassic cooling at the end of the Toarcian, and a long-term warm interval in the Late Jurassic are clearly recorded. From the end of the Ryazanian, a gradual cooling episode began, which apparently continued throughout the Early Cretaceous except for a brief warming episode in the early Aptian. At the beginning of the Late Cretaceous, the climate became warmer; the peak of warming is recorded at the Cenomanian–Turonian boundary. Then, the middle–late Turonian was marked by a relatively cold episode. Later, in the Coniacian–Campanian, the climate warmed again, but at the end of the Campanian another cooling episode occurred. New findings of marine reptiles are described from the Toarcian, Kimmeridgian, Volgian, and Santonian-Campanian deposits of north of Eastern Siberia. All existing records of marine reptiles known from the Jurassic and Cretaceous of Siberia are revised, and all the findings (from 51 localities) are positioned in relation to paleolatitudes. It is established that the majority of occurrences of these fossils were within the polar paleolatitudes (70°–87°). We found no direct correlation between climate fluctuations and the distribution of these organisms. Taking into account the newest data showing that representatives of the majority of Jurassic and Cretaceous large groups of marines reptiles were able to maintain a more or less constant body temperature and were also able to undertake large-scale seasonal migrations, it is reasonable to be cautious in interpreting the presence of remains of these animals as indicators of a warm climate.

中文翻译：

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西伯利亚侏罗纪和白垩纪的海洋爬行动物和气候

摘要-

总结了基于同位素，古生物学和岩性学的西伯利亚侏罗纪和白垩纪气候的所有当前数据。清楚地记录了Pliensbachian晚期的冷却事件，Toarcian的早期变暖，在Toarcian结束时迅速被长期的中侏罗纪冷却所取代，以及侏罗纪晚期的长期暖期。从梁赞期末开始，逐渐降温，除了在阿普提安早期短暂的升温外，整个白垩纪一直在持续。在白垩纪晚期，气候变暖。变暖的峰值记录在西诺曼尼亚-突尼斯边界。然后，中后期的土耳其以相对冷的发作为特征。后来，在科尼亚西亚–坎帕尼亚，气候又变暖了，但是在Campanian结束时，又发生了一次降温事件。从西伯利亚东部北部的Toarcian，Kimmeridgian，Volgian和Santonian-Campanian沉积物描述了海洋爬行动物的新发现。修订了西伯利亚侏罗纪和白垩纪已知的所有海洋爬行动物记录，所有发现（来自51个地区）都与古纬度相关。已经确定，这些化石的大部分出现在极地古纬度内（70°–87°）。我们发现气候波动与这些生物的分布之间没有直接关联。