Pollen analysis of ODP Hole 159-958A@en

Palynological investigation (pollen, spores, and dinoflagellate cysts) of 39 samples from the upper 50 m of Ocean Drilling Program (ODP) Site 958 provides some complementary information about the history of the northeast trade winds and the African Easterly Jet. Unfortunately, with the exception of upper Pliocene sediments from Hole 958A between 31 and 41 mbsf and one other sample at 22.25 mbsf, most of the investigated sediments being of late Pliocene and Pleistocene age showed a poor pollen preservation. Samples with good pollen preservation showed a flora dominated by pine pollen. Pollen from the Sahara was infrequently found indicating that the African Easterly Jet was very weak. The dinoflagellate cyst assemblage is typical for the oceanic environment of the North Atlantic. A hiatus between 44 and 42.50 mbsf is confirmed by the last occurrence of cysts of Invertocysta.对大洋钻探计划（Ocean Drilling Program, ODP）958站位顶部50米的39个样品开展孢粉学调查，分析对象涵盖花粉、孢子与沟鞭藻囊孢（dinoflagellate cysts），该数据集为东北信风与非洲东风急流（African Easterly Jet）的演化历史提供了补充研究资料。 遗憾的是，除958A孔海底以下31~41米（meters below seafloor, mbsf）处的上新统上部沉积物，以及22.25 mbsf处的1个样品外，多数被分析的沉积物形成于晚上新世至更新世时期，其花粉保存状况普遍较差。 花粉保存状况良好的样品，其孢粉植物群以松属花粉占绝对优势。撒哈拉来源的花粉偶有检出，表明当时非洲东风急流强度极弱。 该沟鞭藻囊孢组合具有北大西洋海洋环境的典型特征。通过Invertocysta属囊孢的末次出现层位，证实了海底以下44~42.50 mbsf处存在沉积间断。