湖北省利川地区晚奥陶-早志留纪生产力与还原性地球化学特征
摘要
页岩气的形成和赋存与页岩形成的环境密切相关,页岩生产力和还原性是页岩品质研究的重要内容,本文通过对古海洋生产力与氧化还原地球化学指标调研基础上,以湖北省利川地区晚奥陶-早志留纪页岩钻孔资料为研究对象,开展了有机碳含量,常量、微量、稀土元素,碳、硫同位素,黄铁矿粒径分析等分析测试,研究结果认为,区内晚奥陶-早志留纪黑色页岩段整体可划分为两个阶段,各个阶段的古海洋生产力和古海洋氧化还原条件有明显的变化,第一阶段对应晚奥陶-早志留纪早期,高生产力和缺氧甚至是硫化的地层水体环境,是优质的油、气等资源的母岩,第二阶段对应早志留系中晚期,为贫氧-缺氧的沉积环境,生产力相对第一阶段略低,但仍可作为很好的油、气母岩,整个黑色页岩段均可作为页岩气勘探的有利层段。
引文
[1]华南奥陶—志留系龙马溪组黑色笔石页岩的生物地层学.中国科学(地球科学),42(1):130-139.
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[3]刘光祥。中上扬子北缘中古生界海相烃源岩特征。石油实验地质,2005,27(5):490-495。
[4]Suits,N.S.,Wilkin,R.T.,1998.Pyrite formation in the water column and sediments of a meromictic lake.Geology,26(12):1099-1102.doi:10.1130/0091-7613(1998)026<1099:PFITWC>2.3.CO;2
[5]Canfield D E.Factors influencing organic carbon preservation in marine sediments.Chem Geol,1994,114:315-329
[6]Canfield,D.E.,and Thamdrup,B.,1994.The production of34S-depleted sulfide during bacterial disproportionation of elemental sulfur.Science 266,1973-1975.
[7]Canfield,D.E.,Raiswell,R.,Westrich,J.T.,Reaves,C.M.,Berner,R.A.,1986.The use of chromium reduction in the analysis of reduced inorganic sulfur in sediments and shales.Chem.Geol.54,149-155.
[8]Lyons,T.W.,Severmann,S.,2006.A critical look at iron paleoredox proxies:new insights from modern euxinic marine basins.Geochimicaet Cosmochimica Acta 70,5698–5722.
[9]Jones,B.,Manning,D.A.C.,1994.Comparison of geochemical indices used for the interpretation of palaeoredox conditions in ancient mudstones.Chemical Geology 111,111–129.
[2]雷卞军等。鄂西古生代硅质岩的地球化学特征及沉积环境。沉积与特提斯地质,2002,22(2):70-79。
[3]刘光祥。中上扬子北缘中古生界海相烃源岩特征。石油实验地质,2005,27(5):490-495。
[4]Suits,N.S.,Wilkin,R.T.,1998.Pyrite formation in the water column and sediments of a meromictic lake.Geology,26(12):1099-1102.doi:10.1130/0091-7613(1998)026<1099:PFITWC>2.3.CO;2
[5]Canfield D E.Factors influencing organic carbon preservation in marine sediments.Chem Geol,1994,114:315-329
[6]Canfield,D.E.,and Thamdrup,B.,1994.The production of34S-depleted sulfide during bacterial disproportionation of elemental sulfur.Science 266,1973-1975.
[7]Canfield,D.E.,Raiswell,R.,Westrich,J.T.,Reaves,C.M.,Berner,R.A.,1986.The use of chromium reduction in the analysis of reduced inorganic sulfur in sediments and shales.Chem.Geol.54,149-155.
[8]Lyons,T.W.,Severmann,S.,2006.A critical look at iron paleoredox proxies:new insights from modern euxinic marine basins.Geochimicaet Cosmochimica Acta 70,5698–5722.
[9]Jones,B.,Manning,D.A.C.,1994.Comparison of geochemical indices used for the interpretation of palaeoredox conditions in ancient mudstones.Chemical Geology 111,111–129.