CAJ | 학술논문

粤北棉花坑铀矿床矿体产于一组陡倾的、近南北向展布的构造蚀变带中,在矿体附近多见有细粒花岗质岩脉穿插,通过对该类脉岩的研究表明,其锆石 U Pb 年龄为138．6±1．3 Ma (MSWD＝0?81),属于晚燕山期岩浆活动的产物.脉岩的硅含量高,镁、铁、钙和钛含量低, ACNK 值均＞1?1, CaO/Na2 O值＜0?3,刚玉分子数C＞1?8％,属于典型的 S型花岗岩类；脉岩中富集大离子元素K、Rb、Th而亏损Ba、Sr、Ti和P,稀土总量低,配分模式明显呈海鸥型,且表现出一定程度的“四分组效应”, Eu亏损明显.细粒花岗质脉岩的侵入作用使围岩中的铀活化、预富集,因此铀矿化与其有成因联系.
월북면화갱유광상광체산우일조두경적、근남북향전포적구조식변대중,재광체부근다견유세립화강질암맥천삽,통과대해류맥암적연구표명,기고석 U Pb 년령위138．6±1．3 Ma (MSWD＝0?81),속우만연산기암장활동적산물.맥암적규함량고,미、철、개화태함량저, ACNK 치균＞1?1, CaO/Na2 O치＜0?3,강옥분자수C＞1?8％,속우전형적 S형화강암류；맥암중부집대리자원소K、Rb、Th이우손Ba、Sr、Ti화P,희토총량저,배분모식명현정해구형,차표현출일정정도적“사분조효응”, Eu우손명현.세립화강질맥암적침입작용사위암중적유활화、예부집,인차유광화여기유성인련계.
The uranium ore of Mianhuakeng deposit is produced in a steeply dipping SN trending structre alteration zone in Zhuguang pluton,and fine grain granite veins are found to emplace the wall rocks near the ore.Research on the veins shows that the U Pb ages of zircon in the fine grain granite of the deposit is 138.6±1.3 Ma (MSWD=0.81),the formation period is Late Yanshanian.The granite has a high level of SiO2 ,but a low level of MgO,Fe2 O3 ,CaO and TiO2 ,With the character of ACNK>1.1 ,CaO/Na2 O<0.3 ,C>1.8%,the granite fall into S type.Trace elements in the granite was rich in K,Rb and Th,but poor in Ba,Sr and P.∑REE in the granite is at a low level,but the REE show a Vshaped distribution in chart and has a lower level of Eu.Activation and preconcentration make changes in the wall rocks due to the fine crystalline granite magmatism,so it is closely related to the uranium mineralization.