机构地区: 西北大学地质学系地质系
出 处: 《石油与天然气地质》 2001年第2期158-160,193,共4页
摘 要: 哈南油田阿尔善储层发育构造微裂缝。经显微镜薄片观察,微裂缝的开度区间为10~30μm,延伸长度为 l~3 mm,面积密度为每平方毫米0025 mm。微裂缝是大裂缝的前奏,大裂缝发育区也是微裂缝发育区,微裂缝发育受控于断裂构造,与断裂及大裂缝同向,以NE向为主。经模型观察,双重孔隙介质模型的水驱油方式为裂缝-部分基质孔隙驱油。微裂缝对开发具有双重作用,一方面微裂缝可以改善基质渗流能力,另一方面微裂缝与大裂缝、断层形成断裂网络,对汪水产生不利影响。针对这一特点,在微裂缝发育区域,应采用周期性注水以期提高驱油效果。 Structural fractures developed well in Aershan reservoir, Hanan Oilfield. The width of the micro-fractures is 10~ 30 pin, the length is 1 ~ 3 mm and surface density is 0.025 mm2. The micro-fracture porosity and permeability have been calculated, and the distribution is analyzed. Micro-fractures are preface of macrn-fractures and the macro-fracture developed areas are also micro-fracture developed areas. A sandstone micro-model experiment has been done to investigate the process of displacement between fractures and matrix. Based on the above studies, micro-fractures play two different roles on waterflooding. On one hand, they may improve the permeability of the reservoirs; on the other hand, the together with macro-fractures and faults may improve network, which have bad effect on waterflooding. According to the characteristics of ,micro-fractures in Aershan reservoir, some suggestions such as periodic injection are put forward to improve the effect of waterflodding in fracture-developed areas.
领 域: [石油与天然气工程]