海上新区油气勘探突破典型案例分析及启示

随着陆地勘探程度越来越高，获得大发现的难度越来越大，油气勘探向海域拓展是大势所趋，加快海域新区突破、实现资源有序接替，具有十分重要的战略意义。重点剖析了渤海湾盆地秦皇岛32-6油田、黎凡特盆地塔马尔气田两个海域大发现的勘探历程，梳理每个勘探阶段的指导思想、部署思路及做法，探讨制约突破发现的因素及推动勘探突破的地质认识转变和思想革新。研究显示，盲目跟风追热点、未找到适合的理论指导制约了渤海湾油田发现；客观分析成藏特征，转变思路，以新近系为主要目的层，以生烃凹陷包围的隆起区及其倾没带为主要勘探方向，推动了秦皇岛32-6油田大发现。黎凡特盆地塔马尔气田的发现则归因于储层物源和低成熟生物气的新认识及较高的勘探投入。研究认为，摸清成藏规律是推动大发现的内在动因，尤其是深海前沿领域勘探；关键成藏要素的颠覆性认识是突破关键，保证持续稳定的勘探投入是推动海域新区突破的前提条件。

Analysis on Typical Cases of Offshore Oil and Gas Exploration Breakthrough and Its Enlightenment

It is more and more difficult to make an important discovery owing to increasingly high degree of onshore exploration. There is an inevitable trend for oil and gas exploration to extend into the offshore area. It is of vital strategic significance to accelerate breakthrough in new offshore areas and bring about orderly replacement of resources. This paper analyzes the exploration process of two important offshore discoveries -- Qinhuangdao 32-6 oilfield in the Bohai Bay Basin and Tamar gas field in the Levant Basin. It also elaborates the guiding principles, deployment mindset and methods in each exploration stage and discusses the factors restricting the discoveries from being made and the changes in geological theories and mindset that lead to the exploration breakthroughs. The results indicated that discovery of oilfields in the Bohai Bay was restricted by blind pursuit of the hot spots and failure of being guided by the appropriate theory. Therefore, some measures were taken in the exploration area, such as making an objective analysis of the reservoir characteristics, changing the mindset, regarding the Neogene as the main targeted formation and locating the uplift surrounded with the sourcing sags and its pitching zone as the main exploration orientation, thus accelerating the important discovery of Qinhuangdao 32-6 oilfield. Discovery of Tamar gas field in the Levant Basin was attributed to the new knowledge about the reservoir provenance and low-maturity biogas as well as high investment in exploration. The study indicates that identification of the accumulation law is the internal dynamic factor for the important discovery, exploration of the deepwater frontier area in particular. The subversive understanding of the key accumulation elements holds the key to the breakthrough while continuous and stable investment in exploration is a precondition to accelerate the breakthrough in the new offshore area.