闽西北大银厂地区正长斑岩-花岗斑岩-流纹岩成因及其与铀成矿关系

对火山岩型铀矿床的岩相学和地球化学特征分析后发现，大部分火山岩型铀矿床都发育了一套钙碱性酸性岩-碱性中性岩组合，该套组合都具有较高的高场强元素含量和Ga/Al比值，与A型火成岩类似。它们的成因及其与铀成矿之间的关系仍是地质学家们所关注的热点之一。本项研究选取武夷铀成矿带北段光泽大银厂地区的酸性岩-中性岩组合（正长斑岩-花岗斑岩-流纹岩）展开一系列研究。重点针对光泽大银厂地区正长斑岩-花岗斑岩-流纹岩组合进行岩相学、精细矿物学、地质年代学、主量、微量元素和同位素地球化学及火山岩铀浸取率等方面的研究，以推断研究区正长斑岩-花岗斑岩-流纹岩组合的岩石成因及其在中低温热液型铀矿床成矿过程中所扮演的角色。在此基础上，尝试探讨为什么大部分赋铀矿火山岩都具有A型特征以及中低温热液型铀成矿与具有A型特征的火山岩之间的联系，为铀矿勘探提供一定的理论依据。

By analyzing the petrography and geochemistry of the volcanic rocks related-uranium deposits, we found that most of the volcanic rock-related uranium deposits develop the calc-alkaline acid rocks-alkaline intermediate rocks assemblages. These assemblages contain high contents of high field strength elements and 104Ga/Al ratios which are similar to the A-type igneous rock. Their petrogenesis and relationship with uranium mineralization have proven to be a hot topic in this field till now. The acid rock-intermediate rock assemblages (syenite porphyry-granite porphyry-rhyolite) in Guangze were selected to study. Petrography, mineralogy, geochronology, element and isotope geochemistry and uranium leaching of the syenite porphyry-granite porphyry-rhyolite in Dayinchang area were carried out to investigate their petrogenesis and their implication for medium-low temperature uranium mineralization. Finally, we attempt to discuss why most uranium deposit-host volcanic rocks display A-type igneous characteristics and their relationship with medium-low temperature hydrothermal uranium deposit, for providing new idea for the exploration of the volcanic rocks related uranium deposit in South China.