CAJ | 학술논문

通过野外观测、岩相学及全岩地球化学数据分析，结果表明内蒙古阿拉善右旗杭嘎勒晚二叠世石英二长闪长岩主体岩石与包体的稀土元素特征一致，轻重稀土分馏程度强烈，具弱的负铕异常，稀土配分曲线为向右倾，属轻稀土富集型。石英二长闪长岩显示了 I 型花岗岩的特点。包体与主体岩石同时具有表现出元素 Ce、Nd、Zr 富集，而 Nb、Sr、P、Ti 亏损，显示形成于增生在大陆边缘正常弧花岗岩的特征。AR-SiO2图解显示，主体与包体岩石虽同属钙碱性＋拉斑玄武系列区，显示了同源岩浆演化的特点，在 R 1-R 2图解上，大部分样品集中在碰撞前与碰撞后花岗岩区分界处，以碰撞前为主；在 Nb-Y 图解上，样品落在了火山弧-同碰撞花岗岩区；在 Rb-（Y＋Nb）图解上，样品落在了火山弧花岗岩区，反映石英二长闪长岩形成于板块边缘的岩浆弧环境。LA-ICP-MS 锆石 U-Pb 年龄测定，表明主体岩石年龄为（251．9±2．7）Ma。杭嘎勒晚二叠世石英二长闪长岩为碰撞前火山弧花岗岩，研究区在晚二叠世时属于活动大陆边缘的火山弧。
통과야외관측、암상학급전암지구화학수거분석，결과표명내몽고아랍선우기항알륵만이첩세석영이장섬장암주체암석여포체적희토원소특정일치，경중희토분류정도강렬，구약적부유이상，희토배분곡선위향우경，속경희토부집형。석영이장섬장암현시료 I 형화강암적특점。포체여주체암석동시구유표현출원소 Ce、Nd、Zr 부집，이 Nb、Sr、P、Ti 우손，현시형성우증생재대륙변연정상호화강암적특정。AR-SiO2도해현시，주체여포체암석수동속개감성＋랍반현무계렬구，현시료동원암장연화적특점，재 R 1-R 2도해상，대부분양품집중재팽당전여팽당후화강암구분계처，이팽당전위주；재 Nb-Y 도해상，양품락재료화산호-동팽당화강암구；재 Rb-（Y＋Nb）도해상，양품락재료화산호화강암구，반영석영이장섬장암형성우판괴변연적암장호배경。LA-ICP-MS 고석 U-Pb 년령측정，표명주체암석년령위（251．9±2．7）Ma。항알륵만이첩세석영이장섬장암위팽당전화산호화강암，연구구재만이첩세시속우활동대륙변연적화산호。
The field observation, petrography and geochemical data of the Late Permian quartz monzodiorite show that the REE features of in the Hanggale area of Alax Right Banner are consistent with its pluton. The Enrichment of LREE and the weak negative Eu anomalies show the characteristics of an I-type granite.The depletion of Nb,Sr,P,Ti elements indicates the features of an arc granite accreting on the continental margin.In the R 1-R 2 diagram,most of the samples are concentrated along the boundary between the pre-collision granite and the post-collision granite area. In the Nb-Y diagram,the samples fall into the area of the volcanic arc and the syn-collisional granite. In the Rb-(Y+Nb)diagram,the samples exit in the area of volcanic arc granite.LA-ICP-MS zircon U-Pb dating shows that the age of the main rock body is 251.9±2.7 Ma.The quartz monzodiorite of Hanggale is a pre-collisional volcanic arc granite,and the Hanggale area was a volcanic arc belonging to the active continental margin in Late Permian.