摘要
A stage (the Stage-Ⅲ) of hydrocarbon inclusion with strong brown-red fluorescence is discovered in the Ordovician carbonate reservoir in eastern Tazhong area, which is different from the other parts of Tazhong area. There are three stages of hydrocarbon inclusions which contributed to the hydrocarbon accumulation in this area. Based on the composition characteristics, phase diagrams,temperature and pressure of them, it is proved that the Stage-Ⅲ formed in Yanshan-early Himalayan movement and high-maturity oil from the Cambrian only accumulated in the Middle-Lower Ordovician and Cambrian reservoirs in eastern Tazhong area, which explains the normal oil reservoir can be found in the eastern Tazhong, while condensate reservoirs have been mainly found in the other areas of Tazhong.