邹城市古路口地区金刚石原生矿找矿前景探讨

古路口位于邹城市和滕州市的交界处，属于克拉通内部活动带，是金刚石成矿有利部位。区内发现金刚石储集层出土点4处，超基性苦橄岩管1处；已经查明的苦橄岩管，经激电测深及联合剖面测量，初步断定该岩管倾向SE，倾角较大，近乎直立。自然重砂样品中主要重砂矿物为赤褐铁矿、磁铁矿、锆石、绿帘石、金属球粒、金红石等，石榴子石含量少，2个样品石榴子石在20粒以上，其余含有石榴子石的样品均在10颗以下。经人工重砂样品鉴定，主要重矿物为铬透辉石、闪锌矿、方铅矿、黄铁矿、磁铁矿、铬铁矿等，对其中透辉石及铬铁矿各50颗进行电子探针分析，初步确定了属于S5组、S11组，具备对金刚石找矿的指示作用。该次激电中梯测量，圈定极化率异常2处，异常形态呈NW向近椭圆型，异常峰值达2.0以上，在视电阻率等值线平面图上，对应相对低阻区，推断为含金属矿化引起，局部视极化率升高视电阻率降低。各种找矿信息表明，该区具备金刚石原生矿成矿环境，易于开展金刚石原生矿的勘查研究工作。

Study on Prospecting Prospect of Primary Diamond Ore in Gulukou Area in Zoucheng City

Gulukou area is located in the border of Zoucheng city and Tengzhou city. It belongs to active belt in plate.and is favorable for diamond mineralization. Four diamond excavation sites and one ultrabasic picrite pipe have been found in the area. Through IP sounding and joint profile survey, it is preliminarily concluded that the picrite pipe has the trend of SE with a large dip angle and nearly vertical. As showed by natural heavy sand samples, main heavy minerals are hematite, magnetite, zircon, epidote, metallic spherulite, rutile and so on. The content of garnet is small. The garnet content of two samples is more than 20 grains, and the rest of samples containing garnet are less than 10 grains. Through identification of artificial heavy sand samples, main heavy minerals are chromite diopside, sphalerite, galena, pyrite, magnetite, chromite, etc. As showed by the EPMA analysis of 50 diopside and chromite, they belong to group S5 and group S11, and has indication to diamond prospecting. Through IP middle gradient survey, two abnormal polarizabilities have been delineated, and the abnormal shape is nearly elliptic with the trend of NW. The peak value is more than 2.0. On the plane map of apparent resistivity contour, it is corresponding to the relatively low resistivity area. It is inferred that metal mineralization has increased local apparent polarizability, and decreased apparent resistivity. As showed by prospecting information, there is a primary diamond ore-forming environment in this area. It is easy to carry out the exploration and research of primary diamond ore.