CAJ | 학술논문

本文对位于陕南勉略宁地区铜厂铜矿区与铜成矿作用有关的闪长岩进行了系统的岩石学、锆石U-Pb年代学和地球化学研究,讨论铜厂岩体的岩石成因、成岩物质来源及其地质意义和与铜厂铜矿床的关系.研究结果表明,铜厂闪长岩属于钙碱性-低钾岩系列岩石,以富大离子亲石元素和贫高场强元素为特征,其稀土配分模式为具Eu负异常和Ce异常不明显的轻稀土富集型,与碧口群海相火山岩具有一定相似性和继承性.闪长岩主要来源于壳源或曾受到地壳物质的强烈混染,并没有经历过显著的结晶分异演化,且与铜成矿有密切的关系,为该区主要成矿物质来源之一.岩体形成的大地构造背景属于碰撞隆起-岛弧火山,成矿作用晚于岩体侵入.铜厂闪长岩的锆石SHRIMP U-Pb同位素年龄为842±6.5Ma,早于秦岭造山带的主造山期.该区晋宁期俯冲-挤压造山作用,形成了碧口岩群岛弧火山岩系,铜厂闪长岩可能属于地层.碧口群细碧角斑岩末期火山侵入杂岩,由碧口群火山岩的局部熔融作用形成,其轻稀土的相对富集可能与岩体继承源岩的稀土特征有关.
본문대위우협남면략저지구동엄동광구여동성광작용유관적섬장암진행료계통적암석학、고석U-Pb년대학화지구화학연구,토론동엄암체적암석성인、성암물질래원급기지질의의화여동엄동광상적관계.연구결과표명,동엄섬장암속우개감성-저갑암계렬암석,이부대리자친석원소화빈고장강원소위특정,기희토배분모식위구Eu부이상화Ce이상불명현적경희토부집형,여벽구군해상화산암구유일정상사성화계승성.섬장암주요래원우각원혹증수도지각물질적강렬혼염,병몰유경력과현저적결정분이연화,차여동성광유밀절적관계,위해구주요성광물질래원지일.암체형성적대지구조배경속우팽당륭기-도호화산,성광작용만우암체침입.동엄섬장암적고석SHRIMP U-Pb동위소년령위842±6.5Ma,조우진령조산대적주조산기.해구진저기부충-제압조산작용,형성료벽구암군도호화산암계,동엄섬장암가능속우지층.벽구군세벽각반암말기화산침입잡암,유벽구군화산암적국부용융작용형성,기경희토적상대부집가능여암체계승원암적희토특정유관.
The paper research on the petrological geochronology and zircon SHRIMP U-Pb of Thongchang diorites,Mian-Lue-Ning area,Southern Shanxi Province,China.The results show that the diorites,which belong to low K cale-alkali series rocks,are characterized by comparative losing of medium-high field strong elements in microelements and comparative enrichment of large ion lithophile elements.The Chondrite-normalized REE patterns of the diorites,which are similar and successive with that of Bikou group marine volcanic rocks,belong to the LREE-rich type with obvious negative anomaly of Eu,reflecting its island-arc volcanic features.It is suggested that there is a relationship between the diorites and the mineralization of Cu,the diorites may be one of source of metallogenic mass,and the diorites may come from the earth's crust or consumingly contaminated by the earth's crust with no remarkable crystallization differentiation.The geological setting of the forming of the diorltes was belonging to collision doming-island arc volcanic,and the mineralization was late to the intrusion of the diorites.The diorhes has a SHRIMP zircon U-Pb age of 842±6.5Ma and suggests it belongs to the invasive magma at the late stage of the stratum-Bikou group spilite,and formed by partly melting from Bikou group spilite.The comparative enrichment of LREE of the diorites may relate to inheriting the REE feature of the source of rocks.