塔河大油田新领域的勘探实践

Exploration practices in frontiers of Tahe oilfield

塔河油田“十五”期间完成三级储量163 877.2×104t油当量,其中探明52 226.01×104t油当量。塔河油田奥陶系油藏稳步外扩,勘探层位及领域不断扩大,取得的油气勘探成果可以概括为“三大突破”:①明确了奥陶系岩溶缝洞型储层发育的主控因素和分布规律,实现了塔河油田奥陶系新地区的突破;②碎屑岩领域实现了新层位的重大突破,拓展了塔河油田新的领域;③非背斜圈闭领域获得工业油气流,实现新的圈闭类型的突破。同时,在勘探思路上也取得较大成果:①碳酸盐岩岩溶缝洞型油藏成藏理论的建立是基本探明塔河特大型油田的基础;②加里东中期岩溶的发现为塔河油田向南扩大提供了科学依据;③复式油气藏理论的发展有效指导了碎屑岩领域的勘探;④“前缘隆起与斜坡控制油气富集”认识指导了天山南缘勘探,新发现一大批圈闭,为西北分公司可持续发展奠定了坚实基础。

During the Tenth Five-Year Plan （2001 -2005 ）, the reserves of Tahe oilfield reached 1. 638 772 billion tons of oil equivalent, in which the proved reserves is 522.260 1 million tons of oil equivalent. The boundary of the Ordavician reservoirs in Tahe oilfield expands steadily with its target strata and exploration areas also increasing. The main achievements in oil and gas exploration can be boiled down to the following ‘ three break- throughs＇ ： ①the exploration of the Ordovician in new regions in Tahe oilfield is realized by basing on identification of the main controlling factors of development and distribution pattern of the Ordovician paleokarst reservoirs; ②the exploration of new clasitic rock sequences is actualized, enlarging the exploration area in Tahe oil field; and ③the exploration of new types of traps is achieved with attainment of commercial oil and gas flow in non-anticlinal traps. Meanwhile, great achievements are also made in exploration concepts： ①establishment of the theory of hydrocarbon accumulation in fractured-vuggy paleokarst reservoir lays the foundations for the finding of oversize Tahe oilfield, ②discovery of the middle Caledonian karst provides a scientific basis for the southward expansion of Tahe oilfield,③development of theory of multiple hydrocarbon accumulation effectively guides the exploration of clastic rocks, and ④the concept of ‘ frontal uplift and the slope controlling hydrocarbon accumulation＇ guides the exploration in the southern margin of Tianshan and contributes to the discovery of a number of new traps, putting a cornerstone for the sustainable development of SINOPEC Northwest Petroleum Branch Company.