摘要：

柴达木盆地中、新生界富含微体化石，节肢动物介形类分布尤其广泛，其中Cetacella、Cypridea、Austrocypris、Hemicyprinotus、Cyprideis 和Ilyocypris inermis是晚侏罗世以来各相关层位的标准化石。这些水生生物的绝灭或发生均很迅速，在区域或全球范围内均可对比，具有生物事件地层学意义:Cetacella属的绝灭可能是侏罗、白垩纪之交全球性的古气候降温和气候带变化在柴达木盆地的反映；早白垩世之后Cypridea的迅速衰退是地外因素灾变的结果；中始新世晚期的Austrocypris的绝灭、渐新世Hemicyprinotus的绝灭都与当时地质条件的改变存在着内在的联系；中中新世Cyprideis的爆发推断是青藏高原隆升，导致气候干燥、湖水咸化的结果；而晚更新世晚期I. inermis等介形类动物群的急剧衰减则与全球气候骤然变冷的末次冰期事件有关。

Abstract:

The Mesozoic-Cenozoic in the Qaidam Basin contain abundant microfossils, especially in Ostracoda  among  which  Cetacella、Cypridea、Austrocypris、Hemicyprinotus、Cyprideis and Ilyocypris inermis are index fossils for specific stratigraphical sequences since the Late Jurassic. The extinction or appearance of these Ostracoda  always occurred in a short time interval, and can be correlated locally and globally, so they are of importance in bioeventstratigraphy. This article listed six such biological events in Qaidam Basin and discussed their causes. The extinction of  Cetacella reflected temperature decrease at global scale and changes of palaeoclimate zones during the latest Jurassic and the earliest Cretaceous; The rapid decline of  Cypridea  in the earliest Cretaceous may be a result of the strikes of small planets; at the latest middle Eocene  Austrocypris  became extinct, and at Oligocene  Hemicyprinotus  disappeared. These events related to the changes of the geological conditions at that time. The explosion of  Cyprideis  at the middleMiocene was because the rise of Qinghai-Xizang Plateau which resulted in the dry climate and development of salt lakes. The rapid decrease of Ostracoda in the Late Pleistocene resulted from the last glacial stage in which the global climate became extremely cold.