桂林理工大学学报
桂林理工大學學報
계림리공대학학보
JOURNAL OF GUILIN UNIVERSITY OF TECHNOLOGY
2014年
1期
1-7
,共7页
张良钜%黎琪%阮青锋%曾伟来%李东升%曾南石%刘靖娜
張良鉅%黎琪%阮青鋒%曾偉來%李東升%曾南石%劉靖娜
장량거%려기%원청봉%증위래%리동승%증남석%류정나
玄武岩%沥青%铜矿化矿物%稀土元素%岩浆成因%热液成因%川南
玄武巖%瀝青%銅礦化礦物%稀土元素%巖漿成因%熱液成因%川南
현무암%력청%동광화광물%희토원소%암장성인%열액성인%천남
basalt%bitumen%copper-mineralized minerals%REE%magmatism%hydrothermalism%southern Sichuan
对川南峨眉山玄武岩及其晶洞中的沥青与葡萄石-石英-方解石-铜矿化矿物等集合体的稀土元素特征进行了分析,探讨了玄武岩及其晶洞中的沥青与铜矿化矿物的形成演化关系。岩浆成因的斑状玄武岩,其∑REE、∑LREE较高(平均值分别为242×10-6、216×10-6),∑HREE较低(26×10-6),δEu平均为0.87,δCe平均为0.95。蚀变杏仁状玄武岩属岩浆成因并有后期热液作用的叠加,其∑REE、∑LREE大约是斑状玄武岩的1/2,平均值分别为107×10-6、91×10-6,而∑HREE 平均为16×10-6,虽有所减少,但并不明显,δEu平均为0.97,δCe平均0.92。沥青及晶洞中的葡萄石、自然铜、黑铜矿等属热液成因,它们的∑REE、∑LREE、∑HREE都极低,平均值分别为14×10-6、12×10-6、2×10-6。沥青的δCe平均值为0.70,δEu平均值为0.49,为明显的负异常。因晶洞壁的石英首先形成于氧化环境,其后晶洞内的原油受热不断裂解成固体沥青与天然气,逐渐向还原环境演化并出现明显的Eu亏损,致使成矿溶液中的铜还原为自然铜。沥青的螺旋生长机制及气孔构造证明沥青是由含有机质热液相或气相转变为固相。晶洞中的葡萄石、石英、碳酸盐等矿物的δCe平均值为0.48,为明显的负异常,δEu平均值为0.82,为负异常,这些矿物是氧化环境而非还原环境的产物。
對川南峨眉山玄武巖及其晶洞中的瀝青與葡萄石-石英-方解石-銅礦化礦物等集閤體的稀土元素特徵進行瞭分析,探討瞭玄武巖及其晶洞中的瀝青與銅礦化礦物的形成縯化關繫。巖漿成因的斑狀玄武巖,其∑REE、∑LREE較高(平均值分彆為242×10-6、216×10-6),∑HREE較低(26×10-6),δEu平均為0.87,δCe平均為0.95。蝕變杏仁狀玄武巖屬巖漿成因併有後期熱液作用的疊加,其∑REE、∑LREE大約是斑狀玄武巖的1/2,平均值分彆為107×10-6、91×10-6,而∑HREE 平均為16×10-6,雖有所減少,但併不明顯,δEu平均為0.97,δCe平均0.92。瀝青及晶洞中的葡萄石、自然銅、黑銅礦等屬熱液成因,它們的∑REE、∑LREE、∑HREE都極低,平均值分彆為14×10-6、12×10-6、2×10-6。瀝青的δCe平均值為0.70,δEu平均值為0.49,為明顯的負異常。因晶洞壁的石英首先形成于氧化環境,其後晶洞內的原油受熱不斷裂解成固體瀝青與天然氣,逐漸嚮還原環境縯化併齣現明顯的Eu虧損,緻使成礦溶液中的銅還原為自然銅。瀝青的螺鏇生長機製及氣孔構造證明瀝青是由含有機質熱液相或氣相轉變為固相。晶洞中的葡萄石、石英、碳痠鹽等礦物的δCe平均值為0.48,為明顯的負異常,δEu平均值為0.82,為負異常,這些礦物是氧化環境而非還原環境的產物。
대천남아미산현무암급기정동중적력청여포도석-석영-방해석-동광화광물등집합체적희토원소특정진행료분석,탐토료현무암급기정동중적력청여동광화광물적형성연화관계。암장성인적반상현무암,기∑REE、∑LREE교고(평균치분별위242×10-6、216×10-6),∑HREE교저(26×10-6),δEu평균위0.87,δCe평균위0.95。식변행인상현무암속암장성인병유후기열액작용적첩가,기∑REE、∑LREE대약시반상현무암적1/2,평균치분별위107×10-6、91×10-6,이∑HREE 평균위16×10-6,수유소감소,단병불명현,δEu평균위0.97,δCe평균0.92。력청급정동중적포도석、자연동、흑동광등속열액성인,타문적∑REE、∑LREE、∑HREE도겁저,평균치분별위14×10-6、12×10-6、2×10-6。력청적δCe평균치위0.70,δEu평균치위0.49,위명현적부이상。인정동벽적석영수선형성우양화배경,기후정동내적원유수열불단렬해성고체력청여천연기,축점향환원배경연화병출현명현적Eu우손,치사성광용액중적동환원위자연동。력청적라선생장궤제급기공구조증명력청시유함유궤질열액상혹기상전변위고상。정동중적포도석、석영、탄산염등광물적δCe평균치위0.48,위명현적부이상,δEu평균치위0.82,위부이상,저사광물시양화배경이비환원배경적산물。
The REE characteristics of Emeishan basalt,the bitumen and the aggregates including prehnite, quartz,calcite,copper-mineralized minerals and so on in druses of basalt in southern Sichuan are analyzed. The forming and evolving relationship among basalt,bitumen and the copper-mineralized minerals in geodes are discussed.The high average values ofΣREE,ΣLREE in porphyritic basalt are 242 ×10 -6,216 ×10 -6.But the average value ofΣHREE loss is 26 ×10 -6.The δEu average is 0.87,a weak negative anomaly.The δCe average is 0.95.Alteration amygdaloidal basalt is affected by magmatogenic and late hydrothermalism,theΣREE and ΣLREE are about half REE in basalt,average values are 107 ×10 -6 and 91 ×10 -6,whileΣHREE mean is 16 ×10 -6 .Although the value is lower than that in porphyritic basalt,it is not imperceptible.TheδEu average is 0.97,as well the δCe mean is 0.92.Bitumen and copper,tenorite minerals are formed in hy-drothermal process,the ΣREE,ΣLREE and ΣHREE are much lower,and their values are 14 ×10 -6 ,12 × 10 -6 and 2 ×10 -6.TheδCe in bitumen mean is 0.70 and theδEu average is 0.49.Both are apparently nega-tive anomaly.As quartz grown in the druses swall first formed in oxidation condition,and then heated,crude oil constantly splits into solid bitumen and natura gas.After the condition gradually evolved into reductive envi-ronment,the Eu shows noticeable loss.So the copper in ore-forming fluid was reduced to native copper.The spiral growth mechanism and vesicle structure of bitumen show that the existing form of asphalt transformed or-ganic hydrothermal phase or gas phase into solid phase.The δCe of prehnite,quartz,carbonates and so on in druses average value is 0.48 obviously negative anomaly.The δEu mean is 0.82,negative anomaly too.It is shown that these minerals in druses are grown not in reductive environment but oxidation condition.