山东栾家河断裂带岩石地球化学特征及其意义
Petrogeochemical Characteristics and Significance of Luanjiahe Fault Zone in Shandong Province

栾家河断裂带是胶西北地区一条重要的断裂构造，它出露长约45 km、宽15~260 m，总体展布为北东30？~50？，倾向南东，倾角60？~85？。断裂带显示南东盘下降、北西盘上升，呈右行张裂走滑特点，带内构造岩主要由碎裂岩、构造角砾岩组成，是胶东地区玲珑金矿田的东部边界断裂，备受地质工作者所关注，前人多认为是一条控矿断裂。本次以栾家河断裂带外围花岗岩、花岗碎裂岩的主、微量和稀土元素地球化学资料为依据，研究其化学成分、微量元素和稀土元素在不同岩矿石中的变化情况并得出初步认识。在化学成分方面，外围花岗岩SiO2含量与花岗碎裂岩相比在正常范围内，从带内碎裂岩的化学成分带入带出的相对百分比分析，碎裂蚀变的岩石具有相对较高的Al₂O₃、K₂O、Na₂O、CaO和P₂O₅，可能代表了早期的钾化现象，而SiO₂及Fe₂O₃、MgO、MnO质相对百分比低。K₂O、Na₂O含量的增高钾质交代所致，钾化是一种找矿标志。微量元素方面，断裂带围岩中Au、Cu、Zn元素含量低于正常玲珑花岗岩含量的平均值，但Ag、Pb等元素则普遍含量较高，是平均值的0.5~2倍，这是花岗岩在破碎蚀变过程中有Au元素富集蚀变所致。断裂带中成矿元素Au的含量高于围岩和玲珑花岗岩，反映了栾家河断裂带具有普遍的金元素富集现象。亲硫元素As、Cu、Zn普遍偏低，说明断裂带中硫化物矿化弱，对成矿不利。稀土元素方面，断裂带中碎裂岩具有较低的稀土总量，稀土配分模式具有相似特征，总体右倾型，ΣREE偏低，以富含LREE和HREE亏损为特征，说明断裂带中稀土元素更多的是反映从流体体系中带入相对偏少。通过本次研究并结合有关矿产勘查资料，认为栾家河断裂带是金矿的矿后断裂，它对多金属矿产具一定的控制作用。
The Luanjiahe fault zone is an important fault structure in the northwestern Area of Jiaoxibei outlying 45 km long and 15 - 260 m wide, with an overall distribution is 30？ - 50？ southward, and dip angle is 60？ - 85？. The fault zone shows that the south-eastern plate is falling and the north-western plate is rising, and is characterized by right-lateral tension strike slip. The tectonic rocks in the zone are mainly composed of cataclastic rocks and tectonic breccia, which is the eastern boundary fault of Linglong gold field in Jiaodong area, and has attracted much attention from geologists. The previous thought is a prospecting fault. Based on the geochemical data of the major trace elements and rare earth elements of the granite and granite fragmentation in the periphery of Luanjiahe fault zone, this paper studies the changes of their chemical composition, trace elements and rare earth elements in different rock ores and obtains a preliminary understanding. In terms of chemical composition, peripheral granite SiO₂ content compared with fractured granite rock within the normal range, from the in-band carried off by the chemical composition of cataclastic rock into relative percentage analysis, cataclastic altered rock has a relatively high Al₂O₃, K₂O, Na₂O, CaO and P₂O₅, may represent early potassium phenomenon, and SiO₂ and Fe₂O₃, MgO style, MnO quality, and the relative percentage is low. The increased content of K2O and Na2O is caused by potassium metasomatism, and potassization is a prospecting indicator. In terms of trace elements, the content of Au, Cu and Zn in the surrounding rocks of the fault