塔里木盆地北部奥陶系碳酸盐岩缝洞储层无水采油期影响因素探讨

碳酸盐岩储层无水采油期的长短对实现油田高产稳产具有重要的意义。油井一旦见水其含水上升变快,生产能力就会下降,油井无水期的产能将直接影响油井开发效果。从不同角度分析了塔里木盆地北部地区碳酸盐岩缝洞储层油井无水采油期的相关影响因素,对该区多口生产井的实际生产数据研究表明,油水界面距风化壳顶的厚度以及油水界面之上油层厚度等因素与无水采油期的长短相关联,这2个数值越大,无水采油期越长。因此,可以用研究区各井距风化壳顶的深度和油水界面以上油层厚度值做等值线叠合图,确定研究区的有利开发区域。

Influential Factors of Water-free Production Period on Ordovician Fractural Carbonate Reservoirs in the North of Tarim Basin

The length of water-free production period of carbonate rock reservoirs was of great significance to realize high and stable yields of oilfields.Once water was produced in wells,faster rising of water cut would induce production capacity dropdown,so water-free production period would directly affect the development results of oil wells.The related influential factors of water-free oil production period on fractural carbonate reservoir in northern Tarim Basin were analyzed from different aspects.The studied result of production data of several production wells in the wellblock indicates that the depth between oil-water interface and the top of weathering crust,the production location and the reservoir thickness above the oil-water interface and other factors are associated with the length of water-free production period,the greater the three numbers are,the longer the water-free production period would be.Therefore,the depth between oil-water interface and the top of weathering crust and the reservoir thickness above the oil-water interface of the wells in studied area can be used to draw overlapped contour map to determine favorable development region in the area.