山东胶莱盆地边缘层间滑动角砾岩型金矿地质特征及成矿动力学背景  

Geological Characteristics and Metallogenic Geodynamic Setting of Interlayer-Sliding Tectonic Breccia-Type Gold Deposit in the Margin of the Jiaolai Basin,Shandong Province

作　　者：邹为雷[1] 杨金中[1] 曾庆栋[2] 李光明[2] 张连昌[2] 

机构地区：[1]中国国土资源航空物探遥感中心,北京100083 [2]中国科学院地质与地球物理研究所,北京100029

出　　处：《地质学报》2010年第4期508-517,共10页Acta Geologica Sinica

基　　金：中国科学院创新工程项目"金矿资源战略接替基地若干靶区预测(编号KZCX1-Y-03)";中国科学院黄金"九五"重大项目"山东省重要金成矿区的成矿模式及找矿预测(编号KZ951-A1-404)"联合资助成果

摘　　要：以蓬家夼、大庄子和发云夼为代表的胶莱盆地北缘层间滑动角砾岩型金矿是近年来确立的一种新类型金矿。这种新类型金矿产出于走滑拉分盆地边缘,并受层间滑动断裂的控制。层间滑动断裂是在伸展构造环境下形成的,一般沿大理岩等相对脆性岩层产出,是一条由碎裂岩、角砾岩等张性构造岩构成、具有一定宽度的断裂构造岩带,具有倾向滑移的特点。层间滑动角砾岩型金矿化主要发生在大理岩质碎裂岩、角砾岩等张性构造岩胶结物内。地质研究及硫、碳及氢氧同位素证据表明,成矿物质和成矿流体具有多源性的特点,以源于下地壳及上地幔的深源成矿流体为主,下渗大气降水及盆地流体不同程度地参与了成矿作用过程,对金矿的形成起到了重要的作用。控矿断裂和金矿化的形成与中生代期间华北东部大地构造环境及胶莱盆地的形成演化密切相关。受区域构造应力场的影响,断裂经历了挤压—伸展—挤压的构造过程。中生代中晚期华北东部岩石圈的剧烈拉张减薄及郯庐断裂带的强烈活动为深源成矿流体的形成和大规模上升创造了聚集和运移的条件,金矿即与这次深源岩浆活动密切相关。Interlayer-sliding breccia-type gold deposit,with the Pengjiakuang,Dazhuangzi and Fayunkuang gold deposits as representative deposits of this kind,is a recently-discovered and defined gold deposit in the Jiaolai Basin.The gold deposits of this kind occur mostly along the margin of pull-apart basin and are controlled by interbedded sliding fault.The interlayer sliding fault,formed in the extending tectonic environment and occurring along the layers of brittle rock,is characterized with structural rocks containing cataclastic rock and breccias,faulting structural rock zone with a certain length,and tendency to slide.The interlayer-sliding breccia-type gold mineralization occurs mainly in the cements of marble breccias and cataclastic rocks.The geological research and S,C-O,H-O isotopic evidence shows that the ore-forming material and fluid are characterized with multiple sources,with dominant ore-forming fluids originating mainly from the upper mantle and the lower crust.The meteoric water and the basin fluid to some extents were involved the mineralization,and this played an important role in the gold mineralization.The ore-controlling fault and gold mineralization were related closely to the tectonic setting of East China and evolution of the Jiaolai Basin in Mesozoic.The interlayer-slide fault experienced a tectonic process of compression-extension-compression due to the effect of the regional tectonic stress field.The strong lithospheric thinning of North China lithosphere and intensive tectonic activity of the Tanlu Fault in late Mesozoic provided the condition for the accumulation and uprising of large-scale ore-forming fluid,and the gold mineralization is closely related to this deep magmatic activity.

关 键 词：胶莱盆地 层间滑动角砾岩型金矿 地质特征 成矿动力学 深源流体 

分 类 号：P618.51[天文地球—矿床学]