CAJ | 학술논문

哈达特陶勒盖铅锌矿床处于华北板块与西伯利亚板块交汇部位，是二连浩特-东乌珠穆沁旗多金属成矿带中新发现的一个中型铅锌矿床。矿区内与Pb-Zn矿化有关的花岗岩为隐伏岩体，LA-ICP-MS锆石U-Pb定年显示，花岗岩侵入时间为（125±4.3）Ma，属于燕山期岩浆活动产物。岩石地球化学分析表明，花岗岩具有高硅、高碱（大部分Na<K）、贫铁、弱过铝质的特征（A/CNK=0.99~1.08）；稀土配分模式图具有“M”型四分组效应，轻重稀土分馏不明显，Eu强烈亏损；大离子亲石元素（Rb，K）和Nd，Ta等元素富集，高场强元素（Nb，Ti）和Ba，Sr等元素亏损。研究结果揭示该花岗岩应属于碱性A型花岗岩。Nd-Pb同位素显示该碱性花岗岩主要来源于中元古代上地壳的部分熔融。构造环境判别图解则指示该碱性花岗岩形成于造山后的拉张构造环境。
합체특도륵개연자광상처우화북판괴여서백리아판괴교회부위，시이련호특-동오주목심기다금속성광대중신발현적일개중형연자광상。광구내여Pb-Zn광화유관적화강암위은복암체，LA-ICP-MS고석U-Pb정년현시，화강암침입시간위（125±4.3）Ma，속우연산기암장활동산물。암석지구화학분석표명，화강암구유고규、고감（대부분Na<K）、빈철、약과려질적특정（A/CNK=0.99~1.08）；희토배분모식도구유“M”형사분조효응，경중희토분류불명현，Eu강렬우손；대리자친석원소（Rb，K）화Nd，Ta등원소부집，고장강원소（Nb，Ti）화Ba，Sr등원소우손。연구결과게시해화강암응속우감성A형화강암。Nd-Pb동위소현시해감성화강암주요래원우중원고대상지각적부분용융。구조배경판별도해칙지시해감성화강암형성우조산후적랍장구조배경。
The Hardat Tolgoi Pb-Zn deposit is a medium-sized Pb-Zn deposit recently found in Erenhot-Dongwuqi polymetallic ore belt along the suture zone between the North China plate and the Siberia plate. The granite relevant to the Pb-Zn mineralization in the orefield is a concealed pluton. The LA-ICP-MS zircon U-Pb dating indicates that the granite was emplaced at 125±4.3 Ma and thus was the products of“Yanshanian”magmatism. Detailed geochemical data show that the granite is composed of weakly peraluminous (A/CNK=0.99-1.08) rocks with low iron, high silicon, and high alkali contents (mostly Na<K). The granite is enriched in large-ion lithophile elements (LILEs, such as Rb and K), Nd and Ta, but is depleted in high-field strength elements (HFSEs, such as Nb and Ti), Ba and Sr. The chondrite-normalized REE pattern shows M type with tetrad effect and strong Eu depletion (δEu=0.003~0.013). These results suggest that the alkaline feldspar granite belongs to alkalinity A type granite and was formed in a post-orogenic tectonic environment. Nd-Pb isotopic compositions show that the alkaline feldspar granite was derived from partial melting of the Mesoproterozoic upper crust.