Contribution of Asian dust and volcanic material to the western Philippine Sea over the last 220 kyr as inferred from grain size and Sr-Nd isotopes
Contribution of Asian dust and volcanic material to the western Philippine Sea over the last 220 kyr as inferred from grain size and Sr-Nd isotopes
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根据颗粒大小和 Sr-Nd 同位素推断，过去 220 公里亚洲尘埃和火山物质对菲律宾海西部的贡献
DOI：
10.1002/2016jc012000
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发表时间：
2016-09-01
影响因子：
3.6
通讯作者：
Wang, Hongli
中科院分区：
文献类型：
--
作者：
Jiang, Fuqing;Zhou, Ye;Wang, Hongli
亚洲尘埃和火山物质是西北太平洋的两个主要组成部分。定量区分它们并估算它们的质量积累速率（MARs）对了解区域和全球气候变化具有重要意义。本文介绍了菲律宾海西部碎屑沉积物的粒度组成和不同粒度碎屑沉积物的放射性成因锶（Sr）和钕（Nd）同位素组成。这些新记录表明，不同的粒度分布可能与1)来自中国中西部沙漠和黄土的亚洲沙尘和2)来自吕宋群岛的火山物质有关。利用威布尔函数拟合得到了该亚洲尘埃和火山物质的火星特征。亚洲尘埃和火山物质火星与冰期-间冰期旋回耦合；这些值在冰期比间冰期更高，变化更大。我们认为，亚洲大陆的干旱加剧与太阳日照和轨道偏心率引起的冰体积变化有关，这是驱动菲律宾海西部冰川尘埃高火星的重要机制。尘埃的内部正反馈可能是另一个重要的机制。冰川时期火山物质的显著增加是由高纬度地区冰量和太阳日照驱动的海平面变化和吕宋群岛轨道偏心率和进动周期驱动的厄尔尼诺/南方涛动（ENSO）降水增强引起的。
Asian dust and volcanogenic materials are two major components in the northwestern Pacific. Quantitatively distinguishing them and estimating their mass accumulation rates (MARs) are very important for understanding regional and global climate change. Here we present the grain-size composition of detrital sediments and the radiogenic strontium (Sr) and neodymium (Nd) isotopic compositions of different grain-size fractions of detrital sediments that were recovered from the western Philippine Sea. These new records show that the different grain-size distributions can be associated with 1) Asian dust from the western and central Chinese deserts and Chinese loess and 2) volcanogenic materials that were derived from the Luzon Islands. The MARs of this Asian dust and volcanic materials are obtained by using Weibull-function fitting. The MARs of Asian dust and volcanic materials are coupled with the glacial-interglacial cycle; these values are found to have been higher and more variable during the glacial period than during the interglacial period. We argue that the strengthening aridity of the Asian continent, which is connected to solar insolation and ice volume variations from orbital eccentricity, constitutes an important mechanism that drives the high MARs of glacial dust in the western Philippine Sea. The internal positive feedback of dust may be another important mechanism. The significant increase in volcanic material during the glacial period was caused by sea level changes, which were driven by the ice volume and solar insolation at high latitudes, and by strengthened precipitation from the El Nino/Southern Oscillation (ENSO), which is driven by orbital eccentricity and precession cycles on the Luzon Islands.