摘要
茶地序列分布于福建西部上杭茶地一带,属钙碱性花岗岩,大小侵入体近30个,围岩为震旦系。其锆石U-Pb法年龄介于368—400Ma,时代属早古生代。根据侵入体接触关系及同位素地质年龄,从早到晚划分为陈坑(片麻状似斑状中粒花岗岩)、上三溪(片麻状似斑状细粒花岗岩)、云山(白云母化片麻状似斑状细粒花岗岩)、蓝屋(片麻状细粒碱长花岗岩)等4个岩石单元。由侵入体的地质特征、岩石特征以及岩石化学、稀土元素、微量元素地球化学特征等方面的分析研究结果表明,各单元侵入体依其时代从早到晚,基本反映了同源岩浆继承、发展的演化规律。据此,将陈坑、上三溪、云山、蓝屋等4个岩石单元归并为同源岩浆演化序列——茶地序列。各单元侵入体具有同构造期整合侵入特征,属强力定位机制;形成于陆内板块造山带环境,属S型花岗岩,系加里东造山运动的产物。
Chadi Series is distributed in the Chadi area of Shanghang county,Western Fujian and consists ofnear to 30 intrusive bodies whose country rock is of Sinian.It belongs to calc-alkaline granites whoseisotopic age is 368—400 Ma.Based on the contact relation of the intrusive bodies and the isotopic age,Chadi Series can be divided into four rock units from old to new:Chenkeng Unit(gneissic/porphyritic-like mesograined granite),Shangsanxi Unit(gneissic/porphyritic-like fine-gained granite),YunshanUnit(muscovitizated gneissic/porphyritic-like fine-grained granite)and Lanwu Unit(gneissic fine-grained alkali-feldspar granite).The results of analyzing the intrusive bodies show that the intrusivebodies in each unit present basically the heritage and development for the homologous magma in thearea.Therefore,the four rock units(Chenkeng,Shangsanxi,Yunshan and Lanwu Units)are classifiedinto a comagamitic series—Chadi Series,the intrusive bodies of which possess the character of syntec-tonic concordant intrusions and are formed by forceful emplacement.They are formed in the environ-ment of intracontinent plate orogen belt and belong to the S-type granite which is the product of Caledo-nian orogeny.
出处
《福建地质》
1991年第4期297-308,共12页
Geology of Fujian
