CAJ | 학술논문

巴里坤塔格地区晚石炭世—早二叠世侵入岩主要包括闪长岩、花岗闪长岩、花岗岩和辉绿岩,相互呈侵入接触关系,形成时代在误差范围内一致。在地球化学上,均属过铝质钙碱性和高钾钙碱性系列,富集轻稀土元素、大离子亲石元素以及不相容元素,亏损高场强元素,显示火山弧花岗岩的特征,低 Sr、低 Pb、高 Nd 的同位素组成特征表明该区侵入岩起源于亏损地幔。通过对综合区域地质演化分析,认为巴里坤塔格地区在晚石炭世—早二叠世为后碰撞拉张环境,其侵入岩的岛弧特征可能是由于岩浆源区受过早期俯冲作用的影响。T DM =1076~806 Ma,指示中酸性侵入岩类的来源可能是古亚洲洋俯冲形成的新生陆壳,该陆壳起源于亏损地幔。因此,认为晚石炭世—早二叠世晚期巴里坤塔格与邻区博格达、哈尔里克地区自晚石炭世全面进入板内构造演化阶段。
파리곤탑격지구만석탄세—조이첩세침입암주요포괄섬장암、화강섬장암、화강암화휘록암,상호정침입접촉관계,형성시대재오차범위내일치。재지구화학상,균속과려질개감성화고갑개감성계렬,부집경희토원소、대리자친석원소이급불상용원소,우손고장강원소,현시화산호화강암적특정,저 Sr、저 Pb、고 Nd 적동위소조성특정표명해구침입암기원우우손지만。통과대종합구역지질연화분석,인위파리곤탑격지구재만석탄세—조이첩세위후팽당랍장배경,기침입암적도호특정가능시유우암장원구수과조기부충작용적영향。T DM =1076~806 Ma,지시중산성침입암류적래원가능시고아주양부충형성적신생륙각,해륙각기원우우손지만。인차,인위만석탄세—조이첩세만기파리곤탑격여린구박격체、합이리극지구자만석탄세전면진입판내구조연화계단。
The intrusive rocks of late Carboniferous and early Permian in the Balikuntage area mainly include diorite,granodiorite,granite and diabase.They show intrusive contact relation-ships and their ages are similar within the error range.All the intrusive rocks belong to peralumi-nous calc-alkaline and high-K calc-alkaline series.They are rich in LREE,LILE and incompatible elements,but deficient in HFSE,which are characteristics of the volcanic arc granite.Besides,i-sotopic composition characteristics of high Nd,low Sr and Pb content suggest that the intrusive rocks come from the depleted mantle.Based on the analysis of the regional geological evolution, the tectonic environment of Balikuntage region is the intercontinental rift valley between late Car-boniferous and early Permian,and its island arc characteristics may be induced by the early sub-duction in magma source.The T DM value (1076—806 Ma)reflects that the intermediate-acid intrusive rocks have same source area which is given priority to the partial melting of the juvenile crust,and the source of the young crust is derived from the depleted mantle.It can be deduced that Balikuntage and its adjacent area Bogda and Haerlike fully entered into the intraplate envi-ronment in late Carboniferous and early Permian.