摘要
对大兴安岭富林地区早古生代大伊希康河组、黄花沟组、红水泉组沉积岩进行了系统的碎屑锆石年代学研究,结果表明：①大伊希康河组的碎屑锆石的年龄在458±4～470±4Ma之间,与区域上的多宝山岛弧的火山岩年龄相一致,暗示着额尔古纳地块在早—中奥陶世大伊希康河组沉积时还未隆起;②黄花沟组碎屑锆石年龄谱为431±4～2227±24Ma,与区域上的额尔古纳地块所呈现的几组热事件年龄相一致,表明早志留世黄花沟组接受沉积时额尔古纳地块已经隆升至地表,为周缘盆地提供物源;③红水泉组的碎屑锆石测定年龄值为283±4～780±7Ma,其中283±4Ma为区域上的晚石炭世侵入岩热事件响应的年龄,多数碎屑锆石的测得年龄为333±3～343±3Ma,表明该套沉积物接受沉积时间的下限为333±3Ma;此时,物源区额尔古纳地块的新太古代—古元古代结晶基底已剥蚀殆尽.另外,利用岩石地球化学方法与推测的物源区进行了尝试性的对比研究.
The ages of the detrital zircons from the Paleozoic Formation and Hongshuiquan Formation in Fulin area, Great Hinggan Dayixikanghe Formation, Huanghuagou Mountains were determined. The results showed that： ① the ages of the detrital zircons from the Dayixikanghe Formation are between 458 ± 4 - 470 ± 4Ma, and it is according with the Duobaoshan island-arc volcanic rocks, which indicates that the Ergun block had not uplifted when the Dayixikanghe Formation deposited during Early--Middle Ordovician; ② the age-spectra of the detrital zircons from the Huanghuagou Formation are between 431 ± 4 -2227 - 24 Ma, they are according with a few of hot event time of the Ergun block, also show the Ergun block had uplifted to the earth＇ s surface and afforded provenance to the surrounded basins, when the Huanghuagou Formation deposited during Early Silurian; ③ the ages of the detrital zircons from the Hongshuiquan Formation are between 283 ±4 -780 - 7Ma, of which, the age 283 ±4Ma is according with regional igneous hot event; most ages of the detrital zircons are between 333 ± 3 -343 -3Ma, also show the deposition age is smaller than 333±3Ma, then the material sources of the crystalline basement of the Ergun block were denuded. In addition, we attempt to make geochemical contrasts the above clastic rocks with the source area of matter. Keywords： age of detrital zircon; denuded zone; Great Hinggan Mountains
出处
《地质论评》
CAS
CSCD
北大核心
2015年第2期401-415,共15页
Geological Review
