發(fā)布時間：2019-06-11 05:02

【摘要】：頁巖納米級孔隙的三維結(jié)構(gòu)特征直接決定頁巖氣微觀滲流機理,是完善頁巖儲層流動模型亟需解決的核心問題。本文以龍馬溪組頁巖有機孔樣品(直徑約7μm)為研究對象,分別利用同步輻射納米CT和實驗室納米CT重建有機孔三維空間結(jié)構(gòu),針對兩個裝置獲得的孔隙結(jié)構(gòu)參數(shù)進行對比研究,結(jié)果表明:(1)龍馬溪組頁巖有機孔樣品呈蜂窩狀,孔隙度約60%,連通性較好;孔徑分布呈雙峰模式,集中于60~150nm和500~1400 nm;孔徑大于500 nm的孔隙對樣品的總孔隙度貢獻較大。(2)同步輻射納米CT與實驗室納米CT結(jié)果相較,孔隙度和孔隙總數(shù)兩參數(shù)基本一致,喉道總數(shù)和喉道半徑偏差較大;孔徑分布和配位數(shù)分布規(guī)律雖然類似,但具體數(shù)值存在明顯差異,值得進一步深入比較分析和研究。(3)納米CT方法在頁巖納米孔隙三維結(jié)構(gòu)表征方面存在閾值劃分難度大與掃描視場過小的問題,可從切片重構(gòu)算法、三維數(shù)據(jù)處理、表征單元體三方面進行改進。
[Abstract]:The three-dimensional structure characteristics of shale nano-pores directly determine the microscopic seepage mechanism of shale gas, and it is the core problem to be solved to perfect shale reservoir flow model. In this paper, the organic pore samples of Longmaxi formation shale (about 7 渭 m in diameter) were taken as the research object, and the three-dimensional spatial structure of organic pores was reconstructed by synchrotron radiation nano-CT and laboratory nano-CT, respectively. The pore structure parameters obtained by the two devices are compared and studied. The results show that: (1) the shale organic pore samples of Longmaxi formation are honeycomb, the porosity is about 60%, and the connectivity is good; The pore size distribution is bimodal, concentrated in 60~150nm and 500 鈮，

本文編號：2497027