摘要
对该区燕山期斑岩铜多金属成矿系列进行了REE地球化学研究,并结合岩石化学、包体、微量元素、氢氧同位素综合分析。各(蚀变)岩体REE分布模式可分为三种类型。在乌山矿床Q-Kf、Q-Ser、I-H三个蚀变带中REE分别呈氯化物、F^-络合物、F^-、CO_3^(2-)络合物形式。蚀变是两期叠加的,REE的淋滤、沉淀伴随成矿元素的再活化、再富集。首次发现铕亏损对矿化具有指示意义,蚀变岩δEu愈小,矿化愈好。提出了斑岩体含矿性的五条判别标志,据此对外围岩体含矿性进行了判别排队。
REE geochemical, petrochemical, fluid inclusion, trace element and stable isotope studies have been conducted on the porphyry copper multimetal metallogenic series in this area.The REE patterns in various rockbodies can be divided into 3 types. Rare-earth elements occur as chlorides, F- complex, F- and CO32- complexes in the Q-Kf, Q-Ser and I-H alteration zones of the Wushan deposit. Two phases of alteration are recognized overlapping each other. Following Q-Kf, REE in the porphyry increased (HREE increases more rapidly), ECe/LY decreased and Eu became depleted. 1-H in the wall rock led to strong REE leaching, accompanied by activation and transport of Mo. The inner I-H zone has been superimposed by Q-Ser, leading to redeposition of the previously leached REE and reactivation and re-enrichment of Cu, Mo, Ag, Pb and Zn. This process has a great bearing on mineralization.It has been found for the first time that Eu-depletion is of certain significance in indicating mineralization. Changes in REE patterns in each of the alteration zones at Wushan permit us to establish 5 discrimination criteria for the ore potentiality of porphyries. Jiawula is suggested to be the most prospective area in terms of our criteria.
出处
《地球化学》
CAS
CSCD
北大核心
1989年第4期304-314,共11页
Geochimica
