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| 基金项目：中国地质调查局项目“辽东—吉南成矿带地质矿产调查”（1212011120733） |
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| 摘要： |
| 辽东桓仁地区中生代早白垩世侵入岩发育广泛，通过对辽东桓仁地区中生代早白垩世4期侵入岩的主量元素、微量元素及稀土元素的研究，认为研究区侵入岩为一套以花岗岩、石英二长岩和正长岩为主的中性至酸性岩浆岩，属高钾钙碱性岩-钾玄岩系列，铝过饱和岩石。侵入岩地球化学特征不尽相同，表现为第一期侵入岩具正Eu异常，第二、三、四期侵入岩具负Eu异常；4期侵入岩均富集Rb、Th、K、La等大离子亲石元素（LILE）和轻稀土元素，亏损Ba、Nb、Sr、P、Ti和重稀土元素。研究表明，侵入岩岩浆可能属于陆壳物质的部分熔融产物，并在岩浆上升过程中经历了一定程度的地壳混染和较强的分离结晶作用；侵入岩产出于板内环境和大陆边缘弧构造环境，其动力可能与古太平洋板块俯冲方向改变时的板片撕裂和后撤有关。 |
| 关键词：侵入岩 岩石学特征 地球化学特征 岩石成因 辽宁桓仁 |
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| Abstract: |
| The intrusive rocks in the Early Cretaceous is widely distributed in Huanren area, eastern Liaoning. This paper analyzed the major elements, trace elements and REE of the study area, and concluded that the types of intrusive rocks are mainly intermediate to acid magmatic rocks including granite, adamellite and syenite, which are of high-K calc-alkaline-shoshonite series and rocks of aluminium supersaturation. According to emplacement ages and geochemical features,these intrusive rocks can be divided into four phases. The first phase are of slight positive Eu anomaly. The other three phases are of negative Eu anomaly. Rocks of all four phases are enriched in LILE (Rb, Th, K, La) and LREE, depleted in Ba, Nb, Sr, P, Ti and HREE. The research shows that the intrusive magma was propably derived from the partial melting of the crust, and experienced a certain degree of crustal contamination, strong differentiation and crystallization in its uplifting. Comprehensive analysis shows that the Early Cretaceous intrusion was produced by magma activity within plate and arc setting of continental margin. The driving force of intrusion may be originated from the plate tearing and retreat of the paleo-Pacific plate in its change of subduction direction. |
| Keywords:intrusive rock petrology characteristic geochemistry characteristic genesis Huanren in Liaoning |
| 骆念岗，王彬娜，杨福鹏，等.辽宁桓仁早白垩世侵入岩地球化学特征及成因[J].地质学刊,2017,41(4):587-598 |
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