论文部分内容阅读
本文通过对威远—资阳地区气藏油裂解气的判定,说明威远—资阳地区的气是由石油热裂解而来。在此基础上定量计算了资阳—威远古圈闭油藏的古资源量。资阳—威远地区1900km2范围曾形成过17×108t的古油藏,古油藏裂解形成古气藏,古气藏原始裂解气量可达10576.3928×108m3,质量是7.5832×108t。资阳—威远地区古圈闭碳沥青质量为9.475×108t。原油裂解为天然气可产生致使上覆岩层破裂的138.39MPa的异常高压,超压的存在对于天然气的散失起了很大的作用。随着喜马拉雅期隆升过程和圈闭主高点从资阳向威远的迁移,原油裂解气进一步逸散和重新调整并形成今气藏。在此基础上,恢复了资阳—威远古油藏→资阳—威远古气藏→威远气田的成藏演化过程。资阳—威远地区震旦系天然气的聚集成藏率很低,只有4.835%。因此,资阳—威远古油藏→资阳—威远古气藏→威远气田的演化过程,是天然气以逸散为主的过程。
In this paper, the gas cracked gas in Weiyuan-Ziyang area shows that the gas in Weiyuan-Ziyang area is produced by thermal cracking of oil. On this basis, the ancient resources of Ziyang-Wei ancient trap reservoir were quantitatively calculated. The ancient reservoir of 17 × 108t has been formed in the range of 1900km2 in Ziyang-Weiyuan area. The paleo-gas reservoir was formed by the cracking of paleo-oil reservoirs. The original pyrolysis gas volume of paleo-gas reservoirs can reach 10576.3928 × 108m3 and the mass is 7.5832 × 108t. The paleo-trapping carbon asphalt in Ziyang-Weiyuan area is 9.475 × 108t. The cracking of crude oil into natural gas can produce an abnormal high pressure of 138.39MPa, which causes the overlying rock to rupture. The existence of overpressure plays a very important role in the natural gas loss. With the uplift of the Himalayan period and the transfer of the main peak of the trap from Ziyang to Weiyuan, the cracked gas of crude oil further escaped and readjusted and formed the present gas reservoir. On this basis, the process of hydrocarbon accumulation and evolution of Ziyang-Weiyuan reservoir → Ziyang-Weiyuan reservoir → Weiyuan gas field was resumed. Ziyang - Weiyuan area Sinian gas accumulation rate is very low, only 4.835%. Therefore, the evolution of Ziyang-Weiyuan reservoir → Ziyang-Weiyuan reservoir → Weiyuan gas field is the natural gas-dominated process.