摘要
晴隆锑矿沙子岭火山岩型古油藏的发现,对晴隆锑矿床的成因研究乃至于金属矿和油气勘探均具有重要意义。本文分析了晴隆锑矿古油藏沥青的稀土元素地球化学特征,并将沥青与锑矿及围岩、区域烃源岩的稀土元素作对比分析,探讨古油藏与锑矿成矿关系。结果表明:古油藏中沥青稀土元素ΣREE低,轻重稀土分馏明显,Eu和Ce整体无明显异常,稀土配分属轻稀土富集右倾模式;沥青与锑矿及围岩稀土元素地球化学特征差异较大,二者在稀土质量分数、Ce异常以及配分模式均有明显差异,判定古油藏与锑矿成矿物质和成矿流体来源不同。结合流体包裹体和同位素测试等资料,通过对比沥青与区域烃源岩稀土元素特征,我们认为晴隆锑矿古油藏沥青与泥盆系泥质烃源岩有成因关系;古油藏在演化过程中提供了烃类气体(CH_4),使SO_4^(2-)还原出S^(2-)而参与成矿作用,形成辉锑矿。
The study on Shaziling volcanic rock paleo-oil reservoir is useful for ore genesis study on Qinglong antimony deposit and exploration of antimony deposit and oil reservoir. REE geochemical characteristics of bitumen were analyzed and the metallogenic relationship of paleo-oil reservoir and antimony deposit was discussed in this paper by comparison of REE geochemical characteristics of bitumen, stibnite, host rocks and source rocks. From the result of the analysis, we can draw the following conclusions. First of all, REE content of bitumen is low, and the fractionation of light and heavy rare earth element is obvious. Eu and Ce are normal. REE pattern is the right model for light rare earth element enriched. Secondly, REE geochemical characteristics of bitumen are significantly different between stibnite and host rocks, such as REE content, Ce anomaly and REE pattern. We thus judge that the source of ore-forming reservoir and antimony deposit. Thirdly, materials and ore-forming fluid are different between paleo-oil it is considered that bitumen and argillaceous source rocks of the Devonian have genetic relationship acquired by the comparison of REE geochemical characteristics between bitumen and source rocks, combining with relevant data for fluid inclusions and isotopic dating. Lastly, the paleo-oil reservoir provides the hydrocarbon gases （CH4） to make SO4^2- changing into S2- during the process of stibnite mineralization.
出处
《矿物学报》
CSCD
北大核心
2017年第1期106-113,共8页
Acta Mineralogica Sinica
基金
国家自然科学基金(编号:41362007)
全国危机矿山西南地区典型层控矿床成矿规律总结项目研究(编号:20089943)
国土资源部我国典型金属矿科学基地研究(编号:20091107)
关键词
古油藏沥青
稀土元素
烃源岩
地球化学
晴隆锑矿
paleo-oil reservoir bitumen
REE
source rock
geochemical
Qinglong antimony deposit
