%0 Journal Article %T 鞍山-本溪地区鞍山群含BIF表壳岩形成时代新证据: 锆石SHRIMP U-Pb定年<br>Formation Age of BIF-Bearing Anshan Group Supracrustal Rocks in Anshan-Benxi Area: New Evidence from SHRIMP U-Pb Zircon Dating %A 万渝生 %A 董春艳 %A 颉颃强 %A 谢士稳 %A 刘守偈 %A 白文倩 %A 马铭株 %A 刘敦一< %A br> %A Wan Yusheng %A Dong Chunyan %A Xie Hangqiang %A Xie Shiwen %A Liu Shoujie %A Bai Wenqian %A Ma Mingzhu %A Liu Dunyi %J 地球科学(中国地质大学学报) %D 2018 %R 10.3799/dqkx.2018.004 %X 鞍本是华北克拉通最为重要的BIF铁矿集中区之一,BIF赋存于鞍山群表壳岩中.通过对广泛分布的鞍山群表壳岩的12个样品进行锆石SHRIMP U-Pb定年,大都获得2.50~2.55Ga岩浆锆石年龄,一些岩石中存在2.7~3.5Ga碎屑锆石或外来锆石.一些东北部(东部)岩石记录了新太古代晚期-古元古代早期变质锆石年龄.结合前人研究成果,可得出如下结论:(1)鞍本地区广泛分布的鞍山群含BIF表壳岩形成时代为新太古代晚期;(2)鞍山群表壳岩形成于陆壳基底之上.该研究进一步支持了已有认识:鞍本为东部古陆块西缘新太古代晚期巨型BIF成矿带的重要组成部分,稳定的构造环境有利于大规模BIF形成.<br>Anshan-Benxi is one of the most important BIF concentration areas in the North China Craton, the BIF occurred in the Anshan Group supracrustal rocks. Using SHRIMP U-Pb zircon dating technique, 12 supracrustal samples of the Anshan Group, were analyzed. Most samples present 2.50-2.55Ga zircon ages and 2.7-3.5Ga detrital or xenocrystal zircons are observed in some samples. Combined with previous studies, main conclusions can be drawn as follows. (1) The widespread BIF-bearing Anshan Group supracrustal rocks in the Anshan-Benxi area were deposited during the Late Neoarchean. (2) The Anshan Group supracrustal rocks were formed over a continental basement. This study confirms that Anshan-Benxi is an important conponent of the huge Late Neoarchean BIF belt along the western margin of the eastern ancient terrane, and stable tectonic environment seems to be a key factor for the formation of huge-scale BIF ore deposit %K 鞍山群 %K 新太古代 %K 锆石SHRIMP U-Pb定年 %K 鞍山-本溪地区 %K 岩石学.< %K br> %K Anshan Group %K Neoarchean %K SHRIMP U-Pb zircon dating %K Anshan-Benxi area %K petrology. %U http://www.earth-science.net/WebPage/Article.aspx?id=3727