【摘要】：隨著我國國民經(jīng)濟(jì)的快速發(fā)展,能源問題越發(fā)受到關(guān)注。天然氣水合物作為一種新型能源,主要賦存于海底沉積物和陸地永久凍土帶中,以其巨大的儲量,有望成為未來石油、天然氣重要的接替能源。羌塘盆地是我國公認(rèn)的陸域天然氣水合物成礦條件和找礦前景最好的地區(qū),但至今尚未獲得天然氣水合物存在的直接證據(jù)。近幾年的調(diào)查研究表明,氣源條件成為制約羌塘盆地天然氣水合物找礦突破的關(guān)鍵因素。 本文以羌塘盆地天然氣水合物鉆探試驗井所獲取的巖芯樣品為研究對象,通過系統(tǒng)的有機(jī)地球化學(xué)分析,對多組烴源巖進(jìn)行了評價,進(jìn)而探討了羌塘盆地天然氣水合物成礦氣源條件和成礦潛力。烴源巖評價結(jié)果顯示,(1)上三疊統(tǒng)土門格拉組碎屑巖中發(fā)育一套深灰色-灰黑色為主的泥巖,有機(jī)質(zhì)豐度較高,有機(jī)質(zhì)類型主要為Ⅲ型,熱演化程度較高；(2)下侏羅統(tǒng)曲色組泥巖、油頁巖有機(jī)質(zhì)豐度普遍較高,以Ⅱ2型干酪根為主,較利于油氣的生成,但其熱演化程度處于成熟階段,尚未達(dá)到生成天然氣階段；(3)中侏羅統(tǒng)布曲組灰?guī)r有機(jī)質(zhì)以Ⅱ2型干酪根為主,產(chǎn)油氣潛能中等,且其熱演化程度較高,已進(jìn)入生氣階段,但布曲組灰?guī)r有機(jī)質(zhì)豐度總體不高,僅局部可達(dá)到烴源巖下限；(4)中侏羅統(tǒng)夏里組以中等-差烴源巖為主,有機(jī)質(zhì)多為Ⅲ型,其熱演化程度也較高,達(dá)到了高-過成熟階段；(5)上侏羅統(tǒng)白龍冰河組烴源巖尚處于成熟階段,其有機(jī)質(zhì)豐度較高,以中等烴源巖為主,有機(jī)質(zhì)主要為Ⅱ型。油源對比研究表明,(1)布曲組白云巖分離出的有機(jī)質(zhì)顯示出了與布曲組烴源巖的親緣性,表明其中的油氣顯示可能來源于布曲組烴源巖；(2)曲色組中的液態(tài)油苗與曲色組烴源巖有著極好的親緣性,進(jìn)一步證明了羌塘盆地曲色組具備較強(qiáng)的生烴能力；(3)白龍冰河組中的瀝青與白龍冰河組灰?guī)r親緣性不明顯,但與該組上段的泥質(zhì)烴源巖有一定的相似性,從瀝青脈產(chǎn)狀等現(xiàn)象初步推測瀝青脈與該組泥質(zhì)烴源巖同源,但仍需要進(jìn)一步研究。通過上述研究,并結(jié)合區(qū)域烴源巖分布、沉積厚度等資料,本文認(rèn)為下侏羅統(tǒng)曲色組泥頁巖、上三疊統(tǒng)土門格拉組含煤巖系以及上侏羅統(tǒng)白龍冰河組碳酸鹽巖烴源巖是羌塘盆地較好的的烴源巖,具備較強(qiáng)的生排烴能力,能為天然氣水合物的形成提供較為充足的烴類氣源。綜合天然氣水合物成藏系統(tǒng)的三大體系分析,羌塘盆地具備天然氣水合物形成的良好前景,而上述三套烴源巖應(yīng)作為羌塘盆地下一步天然氣水合物資源勘查的重要目標(biāo)層位。
[Abstract]:With the rapid development of our national economy, energy problems have been paid more and more attention. As a new type of energy, natural gas hydrate mainly exists in seafloor sediments and land permafrost zone. With its huge reserves, gas hydrate is expected to be an important substitute for oil and natural gas in the future. Qiangtang Basin is recognized as the best metallogenic condition and prospecting prospect of natural gas hydrate in China, but no direct evidence for the existence of gas hydrate has been obtained so far. The investigation in recent years shows that the gas source conditions are the key factors restricting the breakthrough of gas hydrate prospecting in Qiangtang Basin. In this paper, the core samples obtained from natural gas hydrate drilling test wells in Qiangtang Basin are taken as the research object. Through systematic organic geochemical analysis, several groups of hydrocarbon source rocks are evaluated. Furthermore, the gas source conditions and metallogenic potential of gas hydrate in Qiangtang Basin are discussed. The results of source rock evaluation show that (1) there is a set of mudstone mainly dark gray and gray black in the clastic rocks of the Upper Triassic Tumen Gela formation. The organic matter abundance is high, the organic matter type is mainly type 鈪，

本文編號：2416682