Western Shandong is one of the typical areas in the North China Craton where granite-greenstone belts were well developed. Supracrustal rocks in western Shandong include the Taishan Group (including the Yanlingguan, Shancaoyu and Liuhang formations) , Jining Group and Mengjiatun Formation. The Taishan Group and Jining Group were once considered as being formed during the Early Neoarchean and Late Paleoproterozoic, respectively. Based on field observation and SHRIMP U-Pb zircon dating, we redefine the times of deposition of supracrustal rocks in western Shandong: 1 ) Supracrustal rocks deposited during the Early Neoarchean (2.75 ~ 2. 70Ga) , including the Yanlingguan Formation and most of the lower part of the Liuhang Formation and the Mengjiatun Formation; 2) supracrustal rocks deposited during the Late Neoarchean (2.55 ~ 2. 525Ga), including the Shancaoyu Formation, the Jining Group, and the upper part and some of the lower part of the Liuhang Formation. They are different in rock association, metamorphism and deformation, with the banded iron formation belonging to the Late Neoarchean supracrustal rock. Western Shandong is the only terrane in the North China Craton where both early and late Neoarchean supracrustal rocks have been identified.%鲁西花岗-绿岩带是华北克拉通早前寒武纪变质基底典型代表.表壳岩系包括泰山岩群、孟家屯岩组和济宁岩群.其中,泰山岩群是鲁西地区规模最大的表壳岩系,曾认为形成于新太古代早期,而济宁岩群曾认为形成于古元古代.根据野外地质和表壳岩系及相关岩石的锆石SHRIMP U-Pb定年,本文对表壳岩系形成时代进行了重新划分.1)新太古代早期(2.70～2.75Ga)表壳岩系,包括原泰山岩群的雁翎关岩组和柳行岩组下段的大部分及孟家屯岩组.2)新太古代晚期(2.525～2.56Ga)表壳岩系,包括原泰山岩群的山草峪岩组、柳行岩组上段和下段的一部分及济宁岩群.它们在岩石组合、变质变形等方面存在明显区别,BIF形成于新太古代晚期.这是华北克拉通迄今唯一分辨出新太古代早期和晚期表壳岩系的地区.
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