墨西哥中新生代岩浆活动规律及成矿研究

Mesozoic-Cenozoic magmatism and mineralization in Mexico

墨西哥中新生代岩浆作用与太平洋板块向东俯冲消减作用及晚白垩-始新世的拉腊米期造山运动有关,岩浆作用控制了矿床的分布规律。文章通过综合分析大量墨西哥中新生代岩浆岩和矿床资料,讨论了岩浆活动规律及构造活动和成矿作用的关系。墨西哥主要有5个岩浆活动时期,分别为晚古生代岩浆作用、早-中侏罗世岩浆作用、白垩世岩浆作用、古近纪岩浆作用、中新世岩浆作用。墨西哥的成矿作用主要与拉腊米期岩浆活动有关(约80 Ma—40 Ma),中新生代的矿床明显分成晚侏罗世(J3)、早白垩世(K1)、晚白垩世(K2)、古新世(E1)、始新世(E2)、渐新世(E3)、中新世(N1)等地质时期。古太平洋板块、法拉隆板块和科科斯板块等三大板块俯冲消减形成3个俯冲成矿系列,即从沿海到内陆依次发育有IOCG型铁铜金成矿带→斑岩型铜钼金成矿带→浅成低温热液型银金多金属成矿带,分别代表太平洋古板块、法拉隆板块和科科斯板块向北美板块从俯冲挤压到碰撞后伸展的岩浆成矿环境。

Mesozoic-Cenozoic magmatism in mexico is related to the Laramide Late-Cretaceous-Eocene orogeny and the eastward subduction of the Pacific Ocean plates and magmatism control the distribution of ore deposits.In this paper large volume data about Mexican Mesozoic-Cenozoic magmatic rocks and ore deposits are analyzed and relationship between the magmatic activity and tectonics/mineralization discussed.Mesozoic-Cenozoic magmatism in Mexico took place mainly in 5 periods,i.e.Late Paleozoic Era,early-middle Jurassic Epoch,Cretaceous Epoch,Paleogene and Miocene.Mineralization is mainly related with Laramide magmatism（ca 80-40 Ma）and took place mainly in Late Jurassic Epoch（J3）,Early Cretaceous Epoch（K1）,Late Cretaceous Epoch（K2）,Palaeocene（E1）,Eocene（E2）,Oligocene（E3） and Miocene（N1）.There are 3 metallogenic series related to subduction of the ancient Pacific plate,Faralon plate and Cocos plate respectively,i.e.IOCG type Fe,Cu,Au ore belt→porphyric Cu,Mo,Au ore belt→epithermal Ag polymetal ore belt from coastal area to inland.