Title: Sphene U-Pb ages of the granitie-granodiorites from Hamyang, Geochang and Yeongju areas of the Yeongnam Massif.
Abstract: U-Pb ages were determined from the granitic rocks from central and northeastern parts of Yeongnam massif. Porphyritic granite of Seosang-myeon, Hamyang-gun near the boundary with Anui-myeon shows age of . Foliated granodiorites of Anui-myeon, Hamyang-gun and Sinwon-myeon, Geochang-gun are and old respectively. Granites from Hari-myeon and Buksang-myeon of Geochang-gun show almost identical ages of and respectively, while foliated granodiorite of Yeongju shows an age ot . Combining with previously reported results, Triassic granitoids were emplaced almost identically at ca. 225 Ma throughout the areas of Hamyang and Sangju oi Yeongnam massif and Baengnok, Jeomchon and Goesan of Okcheon metamorphic belt. There were significant gap of non-magmatism before the resume of granitic activities over the large areas of Hamyang-gun, Geochang-gun, Gimcheon-si and Seongju-gun from Triassic-Jurassic boundary to early Jurassic, 200-194 Ma. Igneous activity within the Yeongnam massif of this period has not been reported from the Okcheon belt or Gyeonggi massif and may reflect distinct tectonic environment. Around 170 Ma, when Yeongju granodiorite was emplaced, there were active granitic magamtism throughout the Yeongnam massif, Okcheon belt and also Gyeonggi massif.
Publication Year: 2006
Publication Date: 2006-01-01
Language: en
Type: article
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Cited By Count: 15
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