【摘要】：方沸石(analcime)是一種富鈉的鋁硅酸鹽礦物,其理想結構的化學分子式為Na16Al16Si32096_16H20,可形成于沉積巖、火山巖等多種成因類型的巖石中,常與其他沸石礦物共生。方沸石在中國新疆地區二疊系中較為發育,對于膠結相中的自生方沸石已有文獻報道,多數都針對其在成巖作用方面的機理與意義,而其他類型的方沸石鮮^有報道。筆者所在的研究團隊近年來在對新疆北部二疊系致密油的研究中發現了含量豐富的方沸石,本文根據研究團隊對準噶爾東部火燒山背斜的中二疊統平地泉組和吉木薩爾凹陷的中二疊統蘆草溝組的研究認識,結合巖石薄片、X衍射、電子探針等方法,對平地泉組及蘆草溝組的方沸石特征及成因進行論述與探討。研究區二疊系平地泉組和蘆草溝組中方沸石主要出現于凝灰巖、沉凝灰巖、凝灰質白云巖、白云巖、灰巖、砂巖與方沸石巖(方沸石含量25%)中。方沸石在沉凝灰巖中廣泛發育,平均含量約7%;凝灰巖中方沸石的分布不均勻,平均含量約3.9%,但21個樣品中僅8個樣品含有方沸石,最高可達23.1%;其他幾種巖性中方沸石含量差別不大,約為6%左右。方沸石發育的巖層常為層狀、透鏡狀構造;微觀上,以自形、半自形及它形三種形態出現。自形方沸石又可根據其產狀結構分為分散粒狀、斑狀與脈狀;半自形方沸石以分散粒狀及團塊狀為主;它形方沸石可見膠結狀與充填狀。火燒山地區Si02含量約為59.6%,吉木薩爾地區約為62.3%,而兩地Al。0A的含量與Na20的含量近似,分別在19%～23%與5.3%～10.4%之間,方沸石的平均Si/Al分別為2.57與2.58,但火燒山地區浮動較大,最小為2.22,最大為2.83。方沸石的巖石學、礦物學特征及物質成分表明方沸石極有可能來源于中-酸性火山巖,通過火山玻璃、長石或粘土礦物與堿性水反.應而來,并且火燒山地區的方沸石具有更為復雜的成因即:有原生方沸石的參與。.方沸石的分布與顯示的區域呈現出良好的匹配度,且方沸石含量的變化趨勢與孔隙度、滲透率的變化趨勢大致相同。方沸石對于儲層的物性的影響體現在:一方面方沸石的存在增加了儲層的滲透率與孑孔隙度,這有利于形成優勢儲層,另一方面方沸石的出現抵抗了壓實作用的影響,因此顆粒間的原生孔隙得以大量保存下來。
[Abstract]:Analite (analcime) is a kind of aluminosilicate mineral rich in sodium. The chemical formula of its ideal structure is Na16Al16Si32096_16H20, which can be formed in sedimentary rocks, volcanic rocks and other types of rocks, and is often symbiotic with other zeolite minerals. The analcite is relatively developed in the Permian system in Xinjiang, China. Most of the literatures have reported the mechanism and significance of the authigenic zeolite in the cemented phase, while the other types have been reported. In recent years, the author's research team has found abundant donalites in the study of Permian dense oil in the northern part of Xinjiang. Based on the understanding of the research team on the Middle Permian Pingdiquan formation in the Huozaoshan anticline in eastern Junggar and the Lucaogou formation of the Middle Permian in the Jimusar Sag, this paper combines the methods of thin rock slice, X-ray diffraction, electron probe and so on. The characteristics and origin of andalite in Pingdiquan formation and Lucaogou formation are discussed and discussed. The Chinese zeolites of the Permian Pingdiquan formation and the Lucaogou formation are mainly found in tuff, dolomite, limestone, sandstone and analite (25% content of clinoptilolite). Analcite is widely developed in sedimentary tuff with an average content of about 70.The distribution of Chinese zeolite in tuff is not uniform, the average content is about 3.9, but only 8 samples of 21 samples contain amotite, the highest is 23.1%. The content of other lithologic Chinese zeolites is about 6%. The rock layers developed by donalites are usually layered and lenticular, and appear in three morphologies: automorphism, hemiautomorphism and heteromorphism microscopically. According to its occurrence structure, it can be divided into dispersed granular, porphyry and vein-like, semi-automorphic andalpinite is mainly dispersed granular and bulk, and it can be seen cemented and filled. The content of Si02 was about 59.6% in Huozaoshan area and 62.3% in Jimusar area, while the content of Al.0A in the two places was similar to that of Na20, ranging from 1923% to 5.3% and 10.4%, respectively. The average Si/Al of donalite is 2.57 and 2.58, respectively, but the minimum is 2.22 and the maximum is 2.83 in the burning mountain area. The petrology, mineralogical characteristics and material composition of donalites indicate that they are most likely derived from intermediate-acid volcanic rocks, which are reversed with alkaline water through volcanic glass, feldspar or clay minerals. In addition, the analcite in the burning mountain area has a more complicated origin, that is, the primary donitic zeolite is involved. The distribution of andalite shows a good match with the displayed area, and the change trend of content of donitic zeolite is similar to that of porosity and permeability. On the one hand, the presence of donalite increases the permeability and solitude of the reservoir, which is conducive to the formation of superior reservoir, and on the other hand, the presence of donosite resists the effect of compaction. As a result, primary pores between particles are preserved in large quantities.
【學位授予單位】：西北大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：P618.13;P578.974
，

本文編號：2298521