CAJ | 학술논문

内蒙古北三段矿区处在华北地台北缘,区内有较多金及多金属矿床,具有良好的区域成矿条件。矿区内晚侏罗世侵入岩以花岗岩、花岗斑岩和石英闪长玢岩为主,具有高 K 和富碱的特点。通过将北三段矿区花岗岩的地球化学数据与国内外不同类型的花岗岩进行对比,判定北三段矿区花岗岩属于 A 型花岗岩,具有富 Si、富碱、贫 Mg 的特点,Sr、P、Eu、Ti 出现低谷,其稀土配分模式曲线呈右倾型,为典型的海鸥式。该类花岗岩可能是在造山运动完成后,岩石圈的伸展减薄环境中形成的。在岩石圈伸展减薄该过程中,局部压力的降低和软流圈的上涌对造成了地壳的部分熔融,从而为花岗岩的形成提供了条件。
내몽고북삼단광구처재화북지태북연,구내유교다금급다금속광상,구유량호적구역성광조건。광구내만주라세침입암이화강암、화강반암화석영섬장분암위주,구유고 K 화부감적특점。통과장북삼단광구화강암적지구화학수거여국내외불동류형적화강암진행대비,판정북삼단광구화강암속우 A 형화강암,구유부 Si、부감、빈 Mg 적특점,Sr、P、Eu、Ti 출현저곡,기희토배분모식곡선정우경형,위전형적해구식。해류화강암가능시재조산운동완성후,암석권적신전감박배경중형성적。재암석권신전감박해과정중,국부압력적강저화연류권적상용대조성료지각적부분용융,종이위화강암적형성제공료조건。
The Beisanduan mining area is located in the northern margin of North China platform, where has good regional metallogenetic condition. There are lots of gold deposits and other poly-metallic deposits in the region. After comparing and discriminating the geochemical data of monzogranite and alkali granite in the Beisanduan mining area with the various types of graniteat home and abroad,the granite in Beisanduan mining area is classified as A type granites,which is rich in Si and alkali,and is poor in Mg. The trace elements (Sr,P,Eu and Ti)present a trough, and the REE patterns show right deviation type,with a typical style of A-typegranite.These granites may be formed in the extension and thinning environment afterorogenic movement. The reduction of local pressure and upwelling of asthenosphere have played a certain role in the partial melting of crust,providing the conditions for the formation of granite.