东海盆地丽水凹陷古新统锆石示踪作用分析

锆石具有较强的稳定性，是地质研究中一种强有力的工具。通过对其形态学研究，再结合其地球化学特征，可讨论其母岩的成因；同时，结合颗粒锆石的微区定年，可以讨论重要的地质事件成因和演化，如锆石的成因和微区离子探针技术在研究造山带构造年代学中发挥着重要作用。利用激光探针等离子体质谱(LAM-ICPMS)技术对丽水凹陷古新统沉积岩中锆石进行微区定年和微量元素测定，并对稀土元素配分模式和微量元素特征进行分析，结果表明，对于复杂来源的锆石，利用其地球化学特征进行区分效果不理想，锆石地球化学特征并不是有利的沉积和锆石来源显示。

ZIRCON TRACING APPLICATION OF PALEOCENE-EOCENE IN LISHUI SAG OF THE EAST CHINA SEA BASIN

Sedimentary mineral assemblages commonly contain detrital zircon crystals as part of the heavy mineral fraction, and zircon is a useful tool in geosciences research because of its stability. We can know its parent rock through zircon morphology and geochemistry and,at the same time,can get some information about some momentous geological events through zircon isotopic dating. A rapid method of REE content determination and isotopic dating for young zircon using Laser Ablation Microprobe-Inductively Coupled Mass Spectrometry has been developed, and we used the method to analyze some zircons of Paleocene-Eocene in Lishui sag and to evaluate the actual variation in REE composition of detrital zircon in a true sediment of a known mixed provenance. The zircon REEs exhibit a narrow abundance range with no systematic differences in pattern shape, and these evidences show zircon geochemical characters and zircon REE patterns are generally not useful as indicators of provenance.