【摘要】 三山岛北部海域金矿床位于胶东西北部三山岛成矿带之内,为一严格受断裂构造控制的超大型破碎带蚀变岩型金矿床。该次找矿预测并获重大突破的预测依据如下:(1)三山岛断裂蚀变矿化带,受NNE和NEE两组方向的区域构造控制,复合叠加呈"N"字形分布。陆上断裂蚀变矿化带接近海域,并没有间断,推测在三山岛北部延伸至海区。(2)焦家和三山岛两断裂蚀变矿化带,具有统一的三维控岩控矿规律。焦家断裂蚀变金矿带向西倾斜,控矿构造和矿化富集程度显示阶梯状分布,其中矿体向南西侧伏,矿体在剖面上呈左行右列式分布;而三山岛断裂蚀变金矿带向东倾斜,其中矿体向NE侧伏,矿体在剖面上呈右行左列式分布。依据陆内构造控岩控矿规律预测海域未知矿体的分布规律,获得了良好的验证。(3)三山岛金矿到焦家金矿的勘探剖面显示,两个控矿构造岩相带倾向相反,但是都在下盘花岗岩区段集中交代蚀变成矿。这一认识为确定深部成矿靶区提供了准确的地质依据。(4)地球物理勘查结果显示,三山岛矿带的重力和磁力异常指出沿"N"字形构造从陆地向海区延伸,这成为预测的重要依据。总之,三山岛北部海域金矿床目前业已取得找矿重大突破。矿床为焦家式破碎蚀变岩型金矿,属中生代燕山晚期岩浆热液脉型矿床,其深部及外围仍具有良好的找矿前景。更多还原

【Abstract】 Located in the Sanshandao metallogenic belt of northeastern Jiaodong,the Sanshandao North Sea gold deposit is an oversized fracture-zone-altered-rock type of deposit.The breakthrough in ore prediction was mainly based on the following investigation results.(1)The Sanshandao fracture-zone-altered-rock belt was controlled by two groups of regional structures in the directions of NNE and NEE.The shape of these structures looks like the letter N.And the fracture-altered-mineralization belt is continuous on land and approaches very closely to the sea.So the mineralization belt should follow the shape"N"to the north part of the sea.(2)The Sanshandao and the Jiaojia fracture-altered-mineralization belts presented a uniform three dimensional ore-controlling model.The Sanshandao fracture-altered-mineralization belt tilts eastward;its orecontrolling structure and the mineralization enrichment level show the ladder-like distribution.And the mine body is of lateral prostration and tilts to the northeast.Mine body in section is distributed on left line.The prediction of unknown mine distribution based on the rock-control and ore-control by land structures has been well verified.(3)From the Sanshandao gold mine to Jiaojia gold mine,the section shows that there are two ore-controlling tectonic lithofacies belts which have opposite dips.But in both of these two belts,the mine body exists in granite area in footwall.This phenomenon is an accurate geological evidence to make sure the metallogenic target in deep area.(4)Geophysical exploration pointed out that the magnetic and gravity anomalies of Sanshandao mine belt extend from land to sea by the shape"N"structure.This is an important evidence to predict unknown ore in deep area.In a word,Sanshandao North Sea gold mine is an ultra-large type of gold mine at present,and it is an ore prospecting breakthrough.The mine is of Jiaojia type,i.e.,a shattered altered rock type of gold deposit,and it is a postmagmatic hydrothermal alteration kata-rocks ore deposit,which was formed by Mesozoic intracontinental magma thermal uplift-detachment.According to the characteristics of the mine,there still are good prospecting potentials.更多还原