冀东黄柏峪-羊崖山地区太古宙岩浆作用和变质作用--SHRIMP锆石U-Pb定年  

Archean magmatism and metamorphism in the Huangbaiyu-Yangyashan area, eastern Hebei Province: Evidence from SHRIMP zircon U-Pb dating

作　　者：孙会一[1] 颉颃强[1] 刘守偈[1] 董春艳[1] 刘敦一[1] 万渝生[1] 

机构地区：[1]中国地质科学院地质研究所,北京离子探针中心,北京100037

出　　处：《地质通报》2016年第1期27-42,共16页Geological Bulletin of China

基　　金：国家自然科学基金项目(批准号:41472169);中国地质调查局项目(编号:12120114021301,1212011220465,1212011120142,1212010811033)

摘　　要：报道了冀东黄柏峪—羊崖山地区太古宙变质辉长岩、黑云斜长片麻岩、片麻状二长花岗岩、片麻状富钾花岗岩等不同类型变质岩浆岩（8个样品）的SHRIMP锆石U-Pb定年结果。首次发现3.1Ga二长花岗岩,黑云斜长片麻岩形成时代约为3.0Ga。变质辉长岩的侵入时代很可能为新太古代晚期,存在少量3.2~3.6Ga捕获锆石。几乎所有岩石样品都记录了约2.5Ga的变质锆石年龄。结合前人资料认为,（1）冀东地区新太古代晚期构造热事件十分发育,被认为与地幔软流圈上涌导致的岩浆板底垫托有关;（2）冀东地区中太古代以前的陆壳物质广泛分布,黄柏峪—羊崖山地区很可能存在一古老陆核。This paper reports SHRIMP zircon U-Pb ages of eight samples for different types of Archean meta-magmatic rocks in the Huangbaiyu-Yangyashan area, eastern Hebei Province, which include meta-gabbro, biotite plagioclase gneiss, gneissic monzogranite and gneissic K-rich granite. 3.1Ga monzogranite （sample J1111） was identified for the first time in the area. Biotite plagioclase gneiss （sample J1116） also probably formed at -3.0Ga. In meta-gabbros （samples Jl109 and Jl110）, which are considered to form at the end of the Neoarchean although no -2.5Ga magmatic zircon age has been determined, there are a few trapped zircons of 3.2- 3.6Ga. Almost all samples record -2.5Ga metamorphic zircon ages. Combined with early studies, the authors have arrived at following conclusions： （1） Tectono-thermal events of the Late Neoarchean were well developed, -2.5Ga metamorphism, mantle magrnatism and crust-derived granite formation were all caused by magma underplating resulting from upwelling of asthenosphere; （2）〉2.8Ga continental materials widely occur in eastern Hebei Province, and there might exist an ancient continental nucleus in the Huangbaiyu- Yangyashan area.

关 键 词：冀东 新太古代 岩浆作用 变质作用 SHRIMP锆石U-PB定年 

分 类 号：P534.2[天文地球—古生物学与地层学] P588.115[天文地球—地质学]