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对俄罗斯远东腾达(Tydna)斯塔诺夫南带南缘混合岩化黑云斜长片麻岩中锆石进行了U-Pb年龄测定和Hf同位素测试,获得其锆石核部年龄主要为≥2.57、~2.39、~2.33和~2.20 Ga,锆石增生边年龄为1.84 Ga,可靠的最年轻碎屑锆石年龄为~2.20 Ga,表明其原岩沉积时代为古元古代,而不是以往认为的太古宙,混合岩化事件年龄为1.84 Ga。锆石核部εHf(t)值为2.7~-16.2,Hf同位素地壳模式年龄为3.7~2.8 Ga;锆石增生边的εHf(t)值为-7.5~-18.6,峰值为-15,Hf同位素地壳模式年龄为3.6~2.9 Ga。锆石的εHf(t)值基本为负值说明这些岩石主要来自于地壳岩石的部分熔融;Hf同位素两阶段模式年龄的峰值在~3.4 Ga,表明它们可能主要来源于阿尔丹地盾下地壳物质的部分熔融。这些年龄资料将为西伯利亚克拉通东南缘地质构造演化提供重要的年代学制约。
The U-Pb dating and Hf isotopic study of zircons in the migmatitic biotite plagioclase gneiss in the southern margin of the southern Stanley southern belt of the Tydna, Russia, have been carried out. The age of the zircon core is ≥ 2.57, ~ 2.39, ~ 2.33, and ~ 2.20 Ga, respectively. The age of proliferating edge of zircon is 1.84 Ga, and the youngest detrital zircon age is ~ 2.20 Ga, indicating that the protolith depositional age was Paleoproterozoic instead of past Of the Archean, the age of the mixed rock was 1.84 Ga. The εHf (t) values of zircons ranged from 2.7 to -16.2 and the Hf isotopic crustal ages ranged from 3.7 to 2.8 Ga. The εHf (t) values of zircons from -7.5 to -18.6 and the peak values from -15 to -19 and Hf isotopes The crustal model age is 3.6 ~ 2.9 Ga. The negative εHf (t) values for zircons indicate that these rocks are mainly derived from the partial melting of the crustal rocks. The Hf isotopic two-stage model peak at ~ 3.4 Ga indicates that they probably originated mainly from crustal materials Part of the melting. These age data will provide important geochronological constraints for the evolution of geological structure in the southeastern margin of Craton, Siberia.