赣东南地区火山地质、矿产特征及找矿方向

赣东南火山岩区主要发育侏罗纪中、晚世中酸性火山碎屑岩－火山熔岩，其中以爆溢相产出的流纹质晶屑凝灰溶岩分布最广；火山构造主要发育破火山口、岩穹、隐爆角砾岩筒等构造，且与成矿关系；与成矿关系密切的次火山岩广泛发育。区内主要矿化类型为斑岩型、（次火山）隐爆层间裂隙带型、蚀变花岗岩型、隐爆角砾岩型，矿床成因均为与火山活动期后次火山（隐爆）活动有关的岩浆期后高－中温热液交代－充填型矿床。同时，矿床类型上具相互穿插性，隐爆层间裂隙带型、隐爆角砾型等矿床类型往往可以看作是斑岩型矿床的延伸；矿床空间分布上往往具有“一体多型”的特征。新矿化类型是赣南中生代火山岩找矿的重要方向。

CHARACTERISTICS OF VOLCANIC GEOLOGY,MINERAL RESOURCES AND ORE-SEARCHING TARGETS IN THE SOUTH-EAST JIANGXI

In the southeast Jiangxi volcanic terrain are mainly developed Middle-Late Jurassic mildly acidic volcanic clastic rocks and volcanic lava,of which the most widely distributed are the explosive-effluent rhyolitic crystal fragment tuff lava;in volcanic structure,largely caldera,volcanic dome and concealed explosive breccia pipe are developed and are intimately related to mineralization;subvolcanic rocks that are closely related with mineralization are also widespread.The main mineralization types in this area are porphyry type,(subvolcanic)concealed explosive interstratal fracture type,altered granite type,and concealed explosive breccia type.In ori-gin,all these types belong to the post-magmatic high-medium temperature hydrothermal replacement-fissure fill-ing deposits related to subvolcanic activity posterior to volcanic activity.However,these deposit types are often intermingled in space:the concealed explosive interstratal fracture type,the altered granite type and the con-cealed explosive breccia type can often be regarded as the extension of the porphyry type,therefore multi-type deposit is common.New mineralization types are an import target in ore searching in the Mesozoic volcanic ter-rain in southeast Jiangxi.