岩石学报
巖石學報
암석학보
ACTA PETROLOGICA SINICA
2009年
8期
1853-1862
,共10页
杨崇辉%杜利林%任留东%万渝生%宋会侠%原振雷%王世炎
楊崇輝%杜利林%任留東%萬渝生%宋會俠%原振雷%王世炎
양숭휘%두리림%임류동%만투생%송회협%원진뢰%왕세염
华北克拉通%安沟群%登封群%SHRIMP锆石年龄
華北剋拉通%安溝群%登封群%SHRIMP鋯石年齡
화북극랍통%안구군%등봉군%SHRIMP고석년령
North China Craton%Angou Group%Dengfeng Group%SHRIMP zircon U-Pb age
华北克拉通南缘安沟群的时代及地层划分对比一直存有争议.侵吞安沟群的许台花岗岩原划为古元古代,本文通过SHRIMP测试,获得其精确的形成年龄为2503±11Ma.安沟群石梯沟组变质酸性火山岩的SHRIMP锆石U-Ph年龄为2521±11Ma,安沟群寨沟组变质酸性火山岩的SHRIMP锆石U-Ph年龄为2517±12Ma,表明安沟群形成于新太古代,与登封群和五台群的形成时代基本一致.安沟群地层的原岩组合为基性火山岩-中酸性火山岩、泥质.碎屑沉积岩和少量碳酸盐岩,总体上与登封群和五台群的原岩组合类似.
華北剋拉通南緣安溝群的時代及地層劃分對比一直存有爭議.侵吞安溝群的許檯花崗巖原劃為古元古代,本文通過SHRIMP測試,穫得其精確的形成年齡為2503±11Ma.安溝群石梯溝組變質痠性火山巖的SHRIMP鋯石U-Ph年齡為2521±11Ma,安溝群寨溝組變質痠性火山巖的SHRIMP鋯石U-Ph年齡為2517±12Ma,錶明安溝群形成于新太古代,與登封群和五檯群的形成時代基本一緻.安溝群地層的原巖組閤為基性火山巖-中痠性火山巖、泥質.碎屑沉積巖和少量碳痠鹽巖,總體上與登封群和五檯群的原巖組閤類似.
화북극랍통남연안구군적시대급지층화분대비일직존유쟁의.침탄안구군적허태화강암원화위고원고대,본문통과SHRIMP측시,획득기정학적형성년령위2503±11Ma.안구군석제구조변질산성화산암적SHRIMP고석U-Ph년령위2521±11Ma,안구군채구조변질산성화산암적SHRIMP고석U-Ph년령위2517±12Ma,표명안구군형성우신태고대,여등봉군화오태군적형성시대기본일치.안구군지층적원암조합위기성화산암-중산성화산암、니질.쇄설침적암화소량탄산염암,총체상여등봉군화오태군적원암조합유사.
The age, stratigraphic division and correlation of the Angou Group on the southern margin of the North China Cratou have been in dispute for a long time. The crystallization age of the Xutai granite which disrupted the Angou Group was once assigned as Paleoproterozoic. In the paper a precise SHRIMP zircon U-Pb age of 2503±11Ma is obtained for the time. As to the Angou Group themselves, the meta-acid volcanics of the Shitigou Formation and the Zhaigou Formation from the complex give the SHRIMP zircon U-Pb ages of 2521±11Ma and 2517±12Ma, respectively. The data show that the Angou Group formed in Neo-Archaean, which is consistent with the formation age of the Dengfeng Group and Wutai Group. In addition, the protolith association of the Angou Group is similar to that of the Dengfeng Group and Wutai Group, too, including the basic and intermediate-acidic volcanics, argitlitic to detrital sediments and minor carbonate rocks.