本文選題：木里煤田 + 侏羅系　； 參考：《地質(zhì)學(xué)報》2017年05期

【摘要】：木里煤田位于青藏高原東北緣,近年在木里煤田聚乎更礦區(qū)中侏羅統(tǒng)窯街組中發(fā)現(xiàn)了天然氣水合物。為了對天然氣水合物氣源類型做出客觀認識,本文對木里煤田聚乎更礦區(qū)中侏羅統(tǒng)窯街組烴源巖樣品的有機質(zhì)豐度、有機質(zhì)類型、有機質(zhì)熱演化程度進行了詳細研究,并在此基礎(chǔ)上對比了研究區(qū)天然氣水合物、煤層氣中烷烴氣的異同,最終確定研究區(qū)天然氣水合物成因類型和氣源。結(jié)果表明:(1)研究區(qū)中侏羅統(tǒng)窯街組的泥質(zhì)烴源巖有機質(zhì)豐度較高,屬好生油巖,有機質(zhì)類型屬于Ⅰ型干酪根,Ro值在0.65%～1.32%之間,有機質(zhì)熱演化程度達到了石油伴生氣階段;(2)天然氣水合物烷烴氣碳同位素特征顯示大部分烷烴氣呈現(xiàn)正碳同位素特征系列,相同碳數(shù)的天然氣水合物烷烴氣碳同位素較煤層氣輕,天然氣水合物烷烴氣中甲烷含量相對煤層氣較低,且天然氣水合物烷烴氣δ13 C2值均小于-28‰,屬于油型氣;(3)中侏羅統(tǒng)窯街組烴源巖碳同位素特征與天然氣水合物的碳同位素具有高度一致性,表明研究區(qū)天然氣水合物氣源主要來自于中侏羅統(tǒng)窯街組的湖相泥巖和油頁巖。
[Abstract]:The Muli coalfield is located on the northeast margin of the Qinghai-Tibet Plateau. In recent years, natural gas hydrate has been found in the middle Jurassic Yaojie formation of Juhuogan coal field in the Muli coal field. In order to make an objective understanding of the gas source types of natural gas hydrate, the abundance of organic matter, the types of organic matter and the thermal evolution of organic matter in the source rock samples of the middle Jurassic Yaojie formation in Juhugan mining area of Muli coal field are studied in detail in this paper. On this basis, the similarities and differences of alkane gas in gas hydrate and coalbed methane in the study area are compared, and the genetic types and gas sources of natural gas hydrate in the study area are determined. The results show that the muddy source rocks of the middle Jurassic Yaojie formation in the study area have high organic matter abundance and belong to the type I kerogen. The Ro value of the source rocks is between 0.65% and 1.32%. The thermal evolution of organic matter has reached the oil-associated gas stage. (2) the carbon isotopic characteristics of alkane gas in natural gas hydrate show that most of the alkane gas shows a series of normal carbon isotopic characteristics. The carbon isotope of natural gas hydrate alkane gas with the same carbon number is lighter than that of coal bed gas, the methane content of natural gas hydrate alkane gas is lower than that of coal bed gas, and the 未 13C2 value of natural gas hydrate alkane gas is less than -28 鈥，

本文編號：2026510