白垩纪被认为是两极无冰的典型温室气候时期,但近年来对于白垩纪存在短暂冰川甚至是极地冰盖的猜想引起了越来越多的关注。根据前人提出的冰川或气候变冷证据,如冰川遗迹、全球海平面快速下降事件以及δ18O正偏事件等,总结了白垩纪可能存在冰川的时期,包括Berriasian-Valanginian之间、Valanginian晚期、Barremiana期、Aptian-Al-bian之交、Albian-Cenomanian之交、Cenomanian中期和末期、Turonian中期、Coniacian中期、Santonian早期、Campa-nian晚期、Campanian-Maastrichtian之交和Maastrichtian末期等。对这些证据的有效性进行详细的讨论,同时也对白垩纪冰川的可能成因进行探讨。笔者认为,白垩纪即便存在冰川,也是小规模、短暂地存在,因此,精确的年代学约束是进行白垩纪冰川研究的前提;米兰科维奇旋回控制下的气候波动是白垩纪形成短暂冰川的可能成因。
The Cretaceous,representing the warmest period during Phanerozoic,contains sparse and frequently equivocal evidences for glaciers or even polar ice sheet.Recently,more and more geoscientists have been interested in the hypothesis of Cretaceous glaciation.This paper compiled the evidences from previous publications including dropstones,tillites,glendonites,eustasy fluctuations and δ18O values.The potential glaciations most possibly existed in the following intervals: Berriasian-Valanginian,late Valanginian,Barremian,Aptian-Albian transition,Albian-Cenomanian boundary,middle and latest Cenomanian,middle Turonian,middle Coniacian,early Santonian,late Campanian,Campanian-Maastrichtian transition and latest Maastrichtian.The Cretaceous glaciers were small and ephemeral if they did exist.It is suggested that the Cretaceous glaciers could exist during short intervals of peak Milankovitch insolation.