摘要
辽南42号金伯利岩岩管主要由东部421号大岩管、西部422号小岩管和中部423号小小岩管组成。421号岩管从地表到40 m标高形态急剧收缩;422号岩管为烟筒状,40 m标高至-160 m标高面积比为1∶1.15;423岩管在-200 m标高处延深为脉状。42号岩管岩石类型为斑状金伯利岩、斑状富金云母金伯利岩、含或富含围岩角砾金伯利岩和含岩球斑状金伯利岩。岩石化学特征研究表明,岩石中w(SiO_(2))、w(Al_(2)O_(3))、w(TiO_(2))值比山东胜利Ⅰ号金伯利岩和戴里值偏高,w(MgO)、w(Cr_(2)O_(3))、w(K_(2)O)、w(Na_(2)O)、w(P_(2)O_(5))值较戴里值偏低,但w(K_(2)O)、w(Na_(2)O)、w(P_(2)O_(5))值比山东胜利Ⅰ号金伯利岩略高;w(ΣFe_(2)O_(3)+FeO)、w(CaO+H_(2)O)值与山东胜利Ⅰ号金伯利岩及戴里值相当。通过采样分析422号岩管金刚石含量高,421号岩管金刚石含量低;研究认为受造岩矿物橄榄石和金云母的影响,金刚石含量与橄榄石斑晶含量正相关,与金云母含量呈负相关;伴生矿物铬铁矿、镁铝榴石、碳硅石含量高,则金刚石含量也随之增高,为正相关;而锐钛矿于金刚石含量为负相关。基于研究区的三维建模、推覆构造研究,推测42号岩管不是根部相,其东部可能存在深部金伯利岩体。
Kimberlite pipe No.42 is mainly composed of the large kimberlite pipe No.42-1 in the east,small pipe No.42-2 in the west and small pipe No.42-3 in the middle.The pipe No.42-1 shrinks sharply from surface to elevation 40 m.Pipe No.42-2 is like a chimney with an area ratio of 1/1.15 from elevation 40 m to elevation-160 m.Pipe No.42-3 turns to a vein at elevation-200 m.Petrologically the kimberlite pipe No.42 is porphyritic kimberlite,phlogopite-rich porphyritic kimberlite,or surrounding rock breccia-rich or rock ball-bearing porphyritic kimberlite.Petrochemically the value of w(SiO_(2)),w(Al_(2)O_(3)),w(TiO_(2))and Daley is higher than those of kimberlite pipe Shengli No.1 in Shandong province,w(MgO),w(Cr_(2)O_(3)),w(K_(2)O),w(Na_(2)O),w(P_(2)O_(5))lower that of Daley value.w(K_(2)O),w(Na_(2)O)and w(P_(2)O_(5))is slightly higher than those of Shengli No.1 kimberlite.The values of w(Fe_(2)O_(3)+FeO)and w(CaO+H_(2)O)of No.42 are similar to those of Shengli No.1 and Daley value.According to sample analysis diamond content in No.42 kimberlite pipe is high,low in No.42-1 and diamond content is influenced by the rock-forming minerals,i.e.positively correlated to that of olivine phenocrystal and negatively to that of pholgopite,positively to those of the acompaying minerals of chromite,Mg-Al garnet moissanite,negatively to anatase.3D modeling and nappe structure study of the area show that No.42 kimberlite pipe has not root facies and the root kimberlite could occur in the east.
作者
刘礼广
朱婉婷
王涛
王旭
LIU Liguang;ZHU Wanting;WANG Tao;WANG Xu(Liaoning Sixth Geological Brigade Co. Ltd, Dalian 116200, Liaoning, China;XU Hongbin StaffInnovation Studio, Dalian 116200, Liaoning, China;Engineering Technology Research Institute of North China Oil Field Branch of China National Petroleum Co. Cangzhou 062550, Hebei, China;Quality, Safety and Environmental Protection Supervision Center of North China Oil Field Branch of China National Petroleum Co., Cangzhou 062550, Hebei, China)
出处
《地质找矿论丛》
CAS
2022年第2期174-190,共17页
Contributions to Geology and Mineral Resources Research
基金
中国地质调查局项目“塞尔维亚铜金资源调查”(编号:DD20201162)
辽宁省自然资源地质勘查“瓦房店金刚石整装勘查区增储专项”(编号:LNZC2019007820)联合资助。
关键词
金伯利岩
金刚石
42号岩管
地质特征
找矿预测
瓦房店辽宁省
kimberlite
diamond
No.42 kimberlite pipe
geological characteristics
prospecting direction
Wafangdian
Liaoning province
