Bergue Cristianini T, Govindan Abiraman
Universidade do Vale do Rio dos Sinos, Laboratório de Micropaleontologia, São Leopoldo, RS, Brazil.
An Acad Bras Cienc. 2010 Sep;82(3):747-60. doi: 10.1590/s0001-37652010000300021.
The Eocene-Pliocene deep sea ostracodes from the ODP site 744A (Kerguelen Plateau) are herein studied under the taxonomic and paleoecologic aspects. 28 species are identified, being the genera Krithe, Cytherella and Dutoitella the most diversified. A faunal threshold was recorded in the Early Oligocene, which is tentatively explained under the knowledge of the paleoceanographical studies carried out not only in the Kerguelen Plateau but also in adjacent areas. The faunal turnover and variations in both richness and abundance possibly reflect the inception of psychrosphere and the influence of hydrological changes in the preservation of carapaces. Moreover, the influence of those changes on carbonate preservation is discussed as the cause of faunal impoverishment in the upper portion of the core.
本文从分类学和古生态学角度对大洋钻探计划（ODP）744A站点（凯尔盖朗高原）始新世 - 上新世的深海介形虫进行了研究。共鉴定出28个物种，其中Krithe属、Cytherella属和Dutoitella属最为多样。在渐新世早期记录到了一个动物群阈值，这一现象暂时依据不仅在凯尔盖朗高原而且在邻近区域开展的古海洋学研究知识进行了解释。动物群的更替以及丰富度和丰度的变化可能反映了低温层的起始以及水文变化对甲壳保存的影响。此外，还讨论了这些变化对碳酸盐保存的影响，认为这是岩芯上部动物群贫化的原因。
