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阜平 (超 )群是华北克拉通中段变质基底的代表性“地层”。阜平大柳树黑云斜长片麻岩常规微量锆石U -Pb法 ( 2 80 0 +2 30- 150 )Ma的年龄 ,既是阜平 (超 )群底部可能为中太古代、也是华北克拉通变质基底为一统太古宙的主要年龄依据。然而 ,阜平 (超 )群传统的地层、年龄和性质一直不断地受到后续研究者质疑 ,现已为许多文献证实不是有序的群级地层而是中 -下地壳性质的杂岩。阜平杂岩的片麻岩种类繁多 ,除了一些学者提出的构造成因的龙泉关片麻岩、TTG质的阜平片麻岩、同构造的片麻状花岗岩等以外 ,本文作者还认为阜平杂岩中的湾子(富铝 )片麻岩可与晋蒙孔兹岩对比。在晋蒙孔兹岩获得了古元古代的沉积年龄之后 ,湾子孔兹岩系是否也可能是古元古代的 ?为证实这个问题 ,本文在阜平杂岩中选取了有代表性的两种片麻岩———阜平大柳树黑云斜长片麻岩 (狭义阜平片麻岩 )和陈庄寒巴的夕线石二云母钾长片麻岩 (湾子孔兹岩 )———分别进行了单颗粒锆石U Pb法测年。结果前者得到 1) ( 2 4 84± 37)Ma不一致线上交点年龄 ,被认为是阜平片麻岩深成结晶年龄 ;2 ) ( 2 332± 7)Ma的谐和年龄 ,可能是持续时间较长的深成作用的结束年龄 ,也可能是深熔作用的年龄。后者得到 1) ( 2 32 6± 30 )Ma的不一致上交点年龄 ,?
The Fuping (super) cluster is a representative “strata” of the metamorphic basement in the middle of the North China Craton. The age of the U-Pb method (2 80 0 +2 30-150) Ma of the Fushui Daliushu biotite plagioclase gneiss in the Fuping period is not only that the bottom of the Fuping (ultra) group may be of the Meso-Archean age, The metamorphic basement is the dominant age-basis of the unified Archean. However, the strata, age and nature of the Fuping (ultra) group have been constantly questioned by the follow-up researchers. Many studies have confirmed that the Fuping (ultra) group is not an ordered group of strata, but a middle-lower crustal complex. Gypsum rocks in Fuping Complex have many kinds of gneiss besides Longquanguan gneiss, TTG-quality Fuping gneiss and tectonic gneiss granite proposed by some scholars. In addition, Fuping Bay (alluvial) gneiss in complex rocks can be compared with the Jin-Mong kondrite. In order to confirm this question, whether the khondalic khondalic rocks of Wanzi were probably ancient Paleoproterozoic since the Paleoproterozoic sedimentary age was obtained in Khond Mongkrit, Species of gneiss --- Fuping Daliushu biotite plagioclase gneiss (Fuping gneiss in the narrow sense) and Chenzhuang Hanbaodi line mica k-gneiss (Wanzi konzei) --- Single grain zircon U Pb method was used for dating. The former results in 1) (2 4 84 ± 37) Ma disagreement, which is considered to be the deep crystallization age of Fuping gneiss. 2) The harmonic age of (2 332 ± 7) Ma may be the duration The ending age of the longer deep action may also be the age of the deep-melting effect. The latter gives 1) (2 32 6 ± 30) Ma inconsistent intersection age.