CAJ | 학술논문

甘肃北山石板井地区隶属东天山古陆东延部分的北山中央古陆断隆构造带，由北山岩群构成古老变质结晶基底岩系。该岩群由具有TTG组合或灰色片麻岩和富铝孔兹岩系构成。获得的同位素年龄为（2757±790）Ma，时代为太古代。侵入其内的中酸性岩获得的同位素年龄分别为(482.3±1.8) Ma~(422±47) Ma和(384.3±2.3) Ma~(332.1±6.8) Ma，分属于加里东期(奥陶-志留纪)和华力西期(晚泥盆-早石炭世)。岩石矿物组合及岩石化学成分揭示，两期岩体岩浆源区与北山岩群有一定相关性。岩石稀土总量较低，与I型花岗岩相似，成因可能为北山岩群的古老变质岩系重熔而形成花岗岩类，为一种后造山岩浆底侵隆升构造环境的产物。
감숙북산석판정지구대속동천산고륙동연부분적북산중앙고륙단륭구조대，유북산암군구성고로변질결정기저암계。해암군유구유TTG조합혹회색편마암화부려공자암계구성。획득적동위소년령위（2757±790）Ma，시대위태고대。침입기내적중산성암획득적동위소년령분별위(482.3±1.8) Ma~(422±47) Ma화(384.3±2.3) Ma~(332.1±6.8) Ma，분속우가리동기(오도-지류기)화화력서기(만니분-조석탄세)。암석광물조합급암석화학성분게시，량기암체암장원구여북산암군유일정상관성。암석희토총량교저，여I형화강암상사，성인가능위북산암군적고로변질암계중용이형성화강암류，위일충후조산암장저침륭승구조배경적산물。
Beishan Shibanjing area in Gansu which on the Beishan middle continental tectonic zone of the East exten-sion part of east tianshan mountain ancient land system is the old metamorphic crystalline basement rock series com-posed by the Northern rock group. The Northern rock group is composed by the TTG group and the AL-rich khondalite series or is composed by the grey gneiss and the Al-rich khondalite series.The isotopic age is (2 757±790) Ma,which be-longed to the Archaeozoic era.The isotopic age of some the intermediate-acid rock is from ( 422 ± 47) Ma to (430 ± 2.5) Ma and the other is from( 361.7±6.8) Ma to (332.1±6.8) Ma,the rock is formed in Caledonian period which from Ordovi-cian to Silurian and variscan which from late Devonian to early carboniferous epoch,respectively.It is revealed by the rock mineral and chemical composition that the rock magma source area in both periods is connection with the Northern rock group.TREO for rocks is low,like the I-type granite.The cause of formation probably is the granide remelt with the old metamorphic rock series.The granite is formed in the post-orogenic magma invade lung tectonic environment.