DISSOLUTION SUSCEPTIBILITY OF SOME PALEOGENE PLANKTONIC FORAMINIFERA FROM ODP SITE 1209 (SHATSKY RISE, PACIFIC OCEAN)
DISSOLUTION SUSCEPTIBILITY OF SOME PALEOGENE PLANKTONIC FORAMINIFERA FROM ODP SITE 1209 (SHATSKY RISE, PACIFIC OCEAN)
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ODP 站点 1209（太平洋沙茨基海隆）的一些古近纪浮游有孔虫的溶解敏感性
DOI：
10.2113/gsjfr.38.4.357
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发表时间：
2008
影响因子：
1.1
通讯作者：
F. Felletti
中科院分区：
文献类型：
--
作者：
M. Petrizzo;Greta Leoni;R. Speijer;B. D. Bernardi;F. Felletti
从古新世/始新世边界到始新世中期基底，对海洋钻探计划地点1209（沙茨基隆起198号站，太平洋）样品的浮游有孔虫组成和壳破碎进行了详细的定量分析，该地层区间以碳酸盐溶蚀增强为特征，而始新世中期基底没有明显的溶蚀层记录。目的是评价古近系化石组合的组成是否具有原始组合的代表性，以及受碳酸盐溶蚀作用的影响程度。通过比较三个最常见的古近系属（Morozovella， Acarinina和Subbotina）的完整标本和碎片的绝对丰度，表明有孔虫碎片属的比例有助于解释化石浮游有孔虫组合受明显碳酸盐溶解影响的古环境。此外，在古新世/始新世边界和始新世收集的三个古近系属的完整标本和片段的绝对丰度表明，与先前的建议相反，刺生的、非共生的、深居的Subbotina比水栖的、共生的、表层生活的Morozovella和Acarinina对溶解的抵抗力更弱。区分古近系浮游有孔虫组合中的原生和潜生信号将是一个重要的挑战，以便更好地约束具有全球意义的古生态和古气候信号。
A detailed, quantitative analysis of planktonic foraminiferal composition and shell fragmentation is presented for samples from Ocean Drilling Program Site 1209 (Leg 198, Shatsky Rise, Pacific Ocean) in a stratigraphic interval from the Paleocene/Eocene boundary, which is characterized by enhanced carbonate dissolution, to the base of the middle Eocene where no distinct dissolution layers are recorded. The aims are to evaluate whether the composition of the fossil Paleogene assemblage is representative of the original assemblage and to what extent it is influenced by carbonate dissolution. By comparing the absolute abundances of whole specimens and fragments of the three most common Paleogene genera ( Morozovella , Acarinina and Subbotina ), it is demonstrated that the percentage of foraminiferal fragments, identified to genus, is helpful in interpreting the paleoenvironment of fossil planktonic foraminiferal assemblages affected by marked carbonate dissolution. In addition, the absolute abundance of whole specimens and fragments of the three Paleogene genera collected at the Paleocene/Eocene boundary and in the Eocene reveal that, contrary to earlier suggestions, the spinose, asymbiotic, deep-dweller Subbotina is less resistant to dissolution than the muricate, symbiont-bearing, surface-dwellers Morozovella and Acarinina . Distinguishing between primary and taphonomic signals in Paleogene planktonic foraminiferal assemblages will be an important challenge to overcome in order to better constrain paleoecologic and paleoclimatic signals of global significance.