海拉尔盆地贝尔断陷苏德尔特变质岩潜山油藏特征

海拉尔盆地贝尔断陷中的变质岩潜山油藏规模大,产量高。变质岩储层在纵向上可分为:风化破碎带,裂缝、溶孔、溶洞发育带和致密带。前两个带储层均具有裂缝和孔洞储油的特点,它们是在长期剧烈的断裂构造活动、风化、淋滤、湖水侵蚀等作用下形成的。变质岩潜山油藏可分为侵蚀残丘块状潜山油藏、反向断块块状潜山油藏、顺向断块层状不规则潜山油藏3种类型,均具有储集物性优越、油质好、产能高的特点。尤其是在反向屋脊高部位,因裂缝、溶孔、溶洞发育而使其油气富集高产。另外,这些潜山的储集特点不受埋深的控制。

Characteristics of metamorphic buried hill reservoir in Sude'erte of Beir Fault Depression in Hailar Basin

The metamorphic buried hill reservoir discovered in Beir Fault Depression of Hailar Basin has a large scale and high oil production. The reservoir can be identified in section as weathered zone (detrition belt), fracture dissolved pore dissolved cave belt and tight zone. The former two zones have the oil storing property in fracture，pore and cave. These zones formed under the actions of some factors such as acute faulting, weathering, leaching and lake water erosion in long term. The massive eroding residual buried hill reservoirs, buried hill reservoirs in inverse fault block and laminate irregular buried hill reservoirs in consequent fault block were commonly found in this area. These oil pools are of favorable property of reservoir, good quality of oil and high production in single well. In particular, oil and gas enriched in high place of the inverse ridge, because fracture, dissolved pore and dissolved cave developed in this place. The accumulation property of buried hill has no relation with buried depth.