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The granitic rocks distributed in Sabangri and Dongcheondong, Gyoungju are divided into biotite granite and alkali-feldspar granite. They have micrographic texture of quartz and alkali-feldspar, miarolitic cavities and low-content of plagioclase. Biotite granites, which are fine-grained rocks, have a variety of biotite shape, a little of mafic clots. Alkali-feldspar granite is coarse-grained rocks, which have biotite and amphibole as interstitial minerals. According to geochemical analysis, Sabangri and Dongcheondong granites are high-K calc-alkaline, metaluminous to peraluminous and highly-fractionated I-type granites or A-type granite because of high SiO2, K2O and Na2O+K2O. They have high LREE and Eu(-) anomaly, low Ba, Sr, P, Ti contents. However, they show some differences between I-type and A-type granites. I-type granites are similar to chemical trend of Cretaceous-Paleogene I-type granites in Gyeongsang Basin, except for Na2O. They have higher K2O content, and lower Rb, Ga, HFSE, HREE contents than A-type granite. In contrast, A-type granite is adjacent to peralkaline, and higher Na2O, Rb, Ga, Y, Ta, HFSE, HREE, total REE, and lower TiO2, Al2O3, CaO, MgO, K2O, P2O5, Ba, Sr than I-type granites. They are also more depleted in Eu, Ba, Sr, P, Ti than I-type granites. Petrological results of I-type granites indicate that they were generated by chemical mixing of magmas that have different physical and chemical components. According to previous studies and petrological, geochemical results of granites, both I-type and A-type granites are thought to have been emplaced during post-orogenic extensional tectonism, Paleogene period.