Pliocene environmental change in West Africa and the onset of strong NE trade winds (ODP Sites 659 and 658)
Pliocene environmental change in West Africa and the onset of strong NE trade winds (ODP Sites 659 and 658)
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西非上新世环境变化和强东北信风的爆发（ODP 站点 659 和 658）
DOI：
10.1016/j.palaeo.2014.09.023
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Schefuß
中科院分区：
文献类型：
--
作者：
Vallé;Dupont;Schefuß
通过对ODP 659站（18°N，21°W）沉积物岩芯的花粉和X射线荧光扫描记录，对西非上新世植被动态和气候变率进行了研究。总的花粉积累率和Ti/Ca比，这是密切相关的灰尘输入在现场之间的比较，表明在多尘期间的花粉的风成运输升高。ODP网站659和附近的网站658的花粉记录的比较导致了一个强大的重建自上新世晚期以来的西非植被变化。在3.6和3.0马之间，西非的萨凡纳与现代的热带草原在组成上有所不同，并且富含菊科植物，特别是Tribus Cichorieae。从Fe/K比推断，在3.24 Ma至3.20 Ma之间存在稳定的湿润期，这可能代表了更窄且更明确的上新世中期（皮亚琴察中期）温暖时间片。森林和萨凡纳草原向北的延伸虽然起伏不定，但在上新世时一般都比较大。东北信风的活力间歇性增加约2.7和2.6马，或多或少永久自2.5马，推断从花粉浓度增加信风指标（麻黄，蒿属，松）。我们的研究结果将东北信风的发展与北方冰川的加剧联系起来。在iNHG之前，很少或没有系统的关系，可以找到北大西洋的海面温度与干旱和灰尘在西非。
Pliocene vegetation dynamics and climate variability in West Africa have been investigated through pollen and XRF-scanning records obtained from sediment cores of ODP Site 659 (18°N, 21°W). The comparison between total pollen accumulation rates and Ti/Ca ratios, which is strongly correlated with the dust input at the site, showed elevated aeolian transport of pollen during dusty periods. Comparison of the pollen records of ODP Site 659 and the nearby Site 658 resulted in a robust reconstruction of West African vegetation change since the Late Pliocene. Between 3.6 and 3.0 Ma the savannah in West Africa differed in composition from its modern counterpart and was richer in Asteraceae, in particular of the Tribus Cichorieae. Between 3.24 and 3.20 Ma a stable wet period is inferred from the Fe/K ratios, which could stand for a narrower and better specified mid-Pliocene (mid-Piacenzian) warm time slice. The northward extension of woodland and savannah, albeit fluctuating, was generally greater in the Pliocene. NE trade wind vigour increased intermittently around 2.7 and 2.6 Ma, and more or less permanently since 2.5 Ma, as inferred from increased pollen concentrations of trade wind indicators (Ephedra,Artemisia,Pinus). Our findings link the NE trade wind development with the intensification of the Northern Hemisphere glaciations (iNHG). Prior to the iNHG, little or no systematic relation could be found between sea surface temperatures of the North Atlantic with aridity and dust in West Africa.
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佛得角高原上的远洋、浊流和沿岸层序沉积（西北非 659 号段 108 段）：新近纪期间的沉积记录 1
DOI：
10.2973/odp.proc.sr.108.138.1989
发表时间：
2006
期刊：
Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences
影响因子：
--
作者：
J. Faugères;P. Legigan;N. Maillet;C. Latouche
通讯作者：
C. Latouche
影响因子：
1.9
作者：
L. Maher
通讯作者：
L. Maher
影响因子：
4.3
作者：
J. Etourneau;C. Ehlert;M. Frank;P. Martinez;R. Schneider
通讯作者：
J. Etourneau;C. Ehlert;M. Frank;P. Martinez;R. Schneider
影响因子：
--
作者：
J. Hennissen;M. Head;S. Schepper;J. Groeneveld
通讯作者：
J. Hennissen;M. Head;S. Schepper;J. Groeneveld
上新世剖面的天文调谐策略：对全球尺度相关性和相位关系的影响
DOI：
10.1098/rsta.1999.0409
发表时间：
1999
期刊：
Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences
影响因子：
--
作者：
S. Clemens
通讯作者：
S. Clemens