对比中国黄土高原中部红黏土序列的锆石 U-Pb 年龄结果。

A comparison of zircon U-Pb age results of the Red Clay sequence on the central Chinese Loess Plateau.

机构信息

Institute of Cenozoic Geology and Environment, State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi' an 710069, China.

Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 73000, China.

出版信息

Sci Rep. 2016 Aug 19;6:29642. doi: 10.1038/srep29642.

DOI:10.1038/srep29642

PMID:27538343

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC4990908/

Abstract

Single grain zircon U-Pb geochronology has demonstrated great potentials in extracting tectonic and atmospheric circulation signal carried by aeolian, fluvial, and fluviolacustrine sediments. A routine in this sort of studies is analyzing 100-150 grains and then compares zircon U-Pb age spectra between the measured sample and the potential sources. Here we compared the zircon U-Pb age results of the late Miocene-Pliocene Red Clay sequence of two neighboring sites from the Chinese Loess Plateau where similar provenance signal is expected. Although the results from the 5.5 Ma sediment support this prediction, the results from the 3 Ma sediment at these two sites differ from each other significantly. These results emphasize the importance of increasing analysis number per sample and combining the zircon U-Pb geochronology with other provenance tools in order to get reliable provenance information.

摘要

单颗粒锆石 U-Pb 年代学在提取风尘、河流和河流湖泊沉积物所携带的构造和大气环流信号方面具有巨大的潜力。在这类研究中，通常会分析 100-150 颗颗粒，然后比较测量样本和潜在来源之间的锆石 U-Pb 年龄谱。在这里，我们比较了中国黄土高原两个相邻地点的晚中新世-上新世红粘土序列的锆石 U-Pb 年龄结果，预计这些地点具有相似的物源信号。尽管 550 万年前沉积物的结果支持了这一预测，但这两个地点 300 万年前沉积物的结果却存在显著差异。这些结果强调了增加每个样本的分析数量，并将锆石 U-Pb 年代学与其他物源工具相结合以获取可靠物源信息的重要性。