發(fā)布時(shí)間：2018-04-11 06:39

  本文選題：揚(yáng)子地區(qū) + 牛蹄塘組　； 參考：《中國地質(zhì)大學(xué)(北京)》2017年碩士論文

【摘要】：本文以揚(yáng)子地塊牛蹄塘組黑色頁巖作為研究對象,通過對牛蹄塘組黑色頁巖樣品進(jìn)行鏡下觀察、X射線粉晶衍射(XRD)及黃鐵礦硫同位素等測試方法,對揚(yáng)子地塊牛蹄塘組黑色頁巖的礦物巖石特征進(jìn)行了分析研究,并且針對牛蹄塘組黑色頁巖中不同成因黃鐵礦進(jìn)行識別與分類,分析了同生黃鐵礦對沉積環(huán)境的指示意義,并得到了一定的認(rèn)識。揚(yáng)子地區(qū)下寒武統(tǒng)牛蹄塘組黑色頁巖礦物成分主要為以石英為主的硅質(zhì)礦物和及以伊利石為主的黏土礦物,并含有少量的碳酸鹽礦物及黃鐵礦。其中以石英為主的硅質(zhì)礦物含量約為54.6%,黏土礦物含量約為34.8%,TOC約為0.04%~9.93%,平均為2.45%;本文通過在光學(xué)顯微鏡和SEM場發(fā)射掃描電鏡下對黃鐵礦的觀察發(fā)現(xiàn),揚(yáng)子地區(qū)下寒武統(tǒng)牛蹄塘組黑色頁巖主要含有同生黃鐵礦和成巖黃鐵礦兩種,而只有同生黃鐵礦具有沉積環(huán)境及對儲層的指示意義;揚(yáng)子地區(qū)牛蹄塘組黑色頁巖中草莓狀黃鐵礦為同生草莓狀黃鐵礦,粒徑集中在4~6μm范圍,中值為5.15μm且變化范圍較窄,指示牛蹄塘組黑色頁巖形成于靜滯-缺氧水體環(huán)境;同生黃鐵礦及成巖黃鐵礦在晶形、產(chǎn)狀、硫同位素值等方面存在顯著差異,同生黃鐵礦的硫同位素(δ34SV-CDT)平均值明顯高于受流體影響成巖黃鐵礦,變化范圍主要集中在19~25‰,平均為21.60‰,且均為17.4‰的正值。指示牛蹄塘組黑色頁巖形成于一種封閉的海洋水體環(huán)境;
[Abstract]:In this paper, the black shale of Niutetang formation in Yangzi block was used as the research object, and the X ray powder diffraction (XRD) and pyrite sulfur isotopes were observed under microscope for the black shale samples of Niulitang formation.The mineral and rock characteristics of black shale of Niulitang formation in Yangzi block are analyzed, and the indication significance of syngenic pyrite to sedimentary environment is analyzed according to the identification and classification of different origin pyrite in black shale of Niulitang formation.And got a certain understanding.The black shale minerals of Niutetang formation of Lower Cambrian in Yangzi area are mainly composed of quartz siliceous minerals and Illite clay minerals with a small amount of carbonate minerals and pyrite.Among them, the content of siliceous minerals, mainly quartz, is about 54.6, and the content of clay is about 34.8TOC is about 0.04 and 9.93, with an average of 2.45.The observation of pyrite by optical microscope and SEM field emission scanning electron microscope shows that,There are two kinds of syngenic pyrite and diagenetic pyrite in the black shale of Niulitang formation of Lower Cambrian in Yangzi area, but only syngenic pyrite has sedimentary environment and indicative significance to reservoir.The strawberry pyrite in the black shale of Niulitang formation in Yangzi area is syngenic strawberry pyrite, the diameter of which is concentrated in the range of 4 ~ 6 渭 m, the median value is 5.15 渭 m and the range of variation is relatively narrow, indicating that the black shale of Niulitang formation is formed in the stagnant and anoxic water environment.There are significant differences between syngenic pyrite and diagenetic pyrite in crystal shape, occurrence and sulfur isotope value. The average value of sulfur isotope (未 34SV-CDT) of syngenic pyrite is obviously higher than that of fluid affected diagenetic pyrite, and the range of variation is mainly 1925 鈥，

本文編號：1734842