胶东埠上金矿煌斑岩地球化学特征及成因

Geochemical Characteristics and Origin of Lamprophyre in Bushang Gold Deposit in Jiaodong Area

摘要:

大量的研究资料表明煌斑岩与金矿在空间上、时间上具明显的对应关系。埠上金矿位于胶东玲珑金矿田西南方向的金岭金矿田的中北部；有关该矿区煌斑岩的研究资料较少。该文结合岩石学、矿物学、大地构造学等特征，对区内煌斑岩的地球化学进行了研究，揭示其内在成因，认为区内煌斑岩是因该区受到古太平洋板块的俯冲、华北板块与杨子板块碰撞造山及郯庐断裂带等构造岩浆活动的影响，俯冲洋壳析出的流体交代地幔形成的具氧化性的EM1型富集型地幔岩浆于造山拉张期在大陆活动边缘浅成侵入而成的。

Abstract:

As showed by a great deal of research data, lamprophyre and gold deposit has obvious corresponding relationship in space and time. Bushang gold deposit is located in the north and central part of Jinling glod mine in the southwest of Linglong gold field in Jiaodong area. Research data of lamprophyres is very less. In this paper, combining with the characteristics of petrology, mineralogy and tectonics, geochemical characterisitcs of lamprophyre in this area have been studied, and the internal causes have been revealled. It is regarded that due to the effects of tectonic magmatic activities, such as the subduction of the paleopacific plate, collision between the North China plate and the Yangzi plate and Tanlu fault zone. EM1 type enriched mantle magma formed by metasomatism of fluid flowed from subducted ocean crust and the mantle intruded into the continental margin in the orogenic extensional period and formed lamprophyre.