兰渝铁路梅岭关隧道浅层天然气预测研究

Prediction and Study of Shallow Reservoired Natural Gas in Meilingguan Tunnel of Lanzhou-Chongqing Railway

从梅岭关隧道所处的构造部位、隧道穿越的地层岩性、隧道与油气构造及油气储层的关系出发,预测该隧道的浅层天然气状况。结合现场钻孔浅层天然气检测结果,研究发现浅层天然气分布主要受构造部位控制,且主要分布在隧道两端向斜翼部,天然气最大浓度为9 740 ppm。综合判定梅岭关隧道为低瓦斯隧道,浅层天然气主要赋存于砂岩孔隙内,以溢流方式向外缓慢溢出。

From Meilingguan Tunnel location, lithologic character of stratum, and the relationship between tunnel and oil gas structure and reservoir, the condition of shllow reservoired natural gas in this tunnel is discussed. Combined with the detection result through drilling shallow reservoired natural gas on site, it is found that the distribution of shllow reservoired natural gas is subjected to tunnel position, which is mainly distributed on both sides to limb, with the maximum density reaching 9740 ppm. Therefore, it is determined that Meilingguan Tunnel is a low gas tunnel, with shllow reservoired natural gas mainly distributed inside the pores of sand rock and flowing out slowly.