【作者】 武卫锋；

【导师】 吕延防；

【作者基本信息】 大庆石油学院 ， 油气田地质工程， 2008， 博士

【摘要】 大庆外围油田勘探开发主要重点集中在长垣及其以东的区域,主要目的层为扶余和杨大城子油层。三肇凹陷扶杨油层经历了预探、评价、试验阶段,提交探明含油面积304.97 km~2,探明地质储量17130.7×10~4t,未动用储量15932×10~4t。总体表现为‘资源探明率低’、‘探明储量动用率低’特点。做为今后主要接替产能的扶杨油层,评价力度逐年加大,虽然经过油藏描述、开发前期的优选布井,扶杨油层钻井成功率仍然较低,主要原因是钻遇水砂或储层发育差而报废。钻探成功率低的根本原因是扶杨油层地质条件复杂,主要体现在三个方面:一是断裂系统复杂;二是三肇凹陷扶杨油层处于物源交汇区,河道展布规律不清;三是二者时空耦合与油气成藏关系复杂。基于扶杨油层成藏的三个主要矛盾,改变传统石油地质的研究模式,从断裂系统出发,剖析断裂与砂体、与油气关系,探索‘用断裂系统’找油的方法。为此本文在全面收集三肇凹陷扶杨油层地震、钻井、试油和开发动态数据的基础上,深入剖析断裂发育特征、活动规律及演化历史,系统分析断裂控藏机制及油气富集规律,明确了扶杨油层下一步勘探方向。扶杨油层断裂走向以南北向为主、规模小、密度大、平面分布不均、断层组合类型多样、具有密集成带的特征,不同方位断裂密集带具有不同的成因机制:北北西和北北东向断裂密集带是受基底断裂和斜拉作用(扭动)产生的;近南北向断裂密集带是同向铲式基底断裂及其水平拆离作用的结果;近东西向断裂密集带为差异伸展作用形成的‘调节型’断裂密集带。三肇凹陷断裂具有7个形成活动时期:早白垩世早期、青一段沉积时期、姚家组沉积时期、嫩江组一二段沉积时期、嫩江组末期、明水组末期和古近系末期。基于断裂形成活动时期,认为扶杨油层由4类不同活动规律的断层构成:即坳陷期断裂、断陷期形成坳陷期继续活动的断裂、断陷期形成坳陷期和反转期均活动的断裂和坳陷期形成构造反转期继续活动的断裂,其中第3、4类断层为油源断层,且多为断裂密集带的边界断层。基于三肇凹陷南部F1油层组‘单砂体级’等时地层格架建立和沉积微相研究,认为河道砂体主要为北东向展布,油源通断断层以近南北向为主,断层与河道斜交构成有利的断层—岩性圈闭。断裂密集带不是主要的富油构造,首次提出‘油主要聚集在油源断层下盘河道砂中’,断裂密集带为‘V’字型‘地堑’式断层组合,是构造相对低部位;油源断层多为断裂密集带的边界断层,断裂密集带不是‘倒灌’油运移的指向区,油主要向阻力较小的下盘方向充注。因此油源断层下盘河道砂是主要的富集区域,油源断层控制的‘地垒’更有利于油富集。按着‘避开断裂密集带,在油源断层控制的地垒或断阶上’找有利评价区原则,提出‘59个评价目标区’,进一步明确了下一步勘探目标。更多还原

【Abstract】 Daqing oilfield exploration and development of the external focus in the east of the placanticline and placanticline, the main purpose formations are the Fuyu and Yangdachengzi formation. The Fuyang formation of Sazhao depression experienced a pre-exploration, evaluation, the pilot phase, and the proved oil-bearing area is 304.97 km², proved geological reserves is 17130.7×10⁴t, unproduced reserves is 15,932×10⁴t. Overall performance as’ low rate of proved resources’, ’ low rate of the using of proved reserves ’ characteristics. As a major future production, the evaluation intensity of Fuyang formation increases year after year. Although through the reservoir description and placing of wells optimization in the early-stage of the development, the success drilling rate of Fuyang formation remains low, the main reasons are drilling water sand or poor abandoned reservoir. The main reason of the low success drilling rate is complex geological conditions of Fuyang formation, mainly in the following three aspects: First, fault system is complex; Second, Fuyang formation of Sanzhao depression lay in the intersection of the source area, the distribution of river is unclear; Third, it is both time and space coupled with the complex relationship between oil and gas accumulation. Based on the three major contradictions of the Fuyang formation oil and gas accumulation, change the traditional model of petroleum geology, start from the fault system, analysis the relationship between fault and sand, and the oil and gas, explore ’fault system using’ method to finding oil. In this paper, based on the comprehensive collection of seismic, well drilling, testing for oil and development dynamic data of Sanzhao Depression Fuyang formation, we analysis faults growth characteristics, the action law and evolution history, analysis fault control reservoir mechanism and regular pattern of rich oil and gas concentration, and define the next step exploration direction of Fuyang formation.The characteristics of faults in F,Y oil layers are that the strike is main of NW, the scale is primarily small, the density is big, the plane distribution is uneven, the fault combination type diverse and they crowded distribute as belt. The belts of faults which strike is NNW and NNE are the result caused by the fundamental faults and Cable-Stayed role （twisting）; The belts of faults concentration have different genetic mechanisms: submeridional zone of faults are the cause of synthetic listric fundamental faults and their horizon decoupling function;. The belts of faults which strike is WE are the "regulation" belts of faults caused by differential extension function. The faults in Sanzhao depression are formed in 7 period: Initial early Cretaceous, the period of qn1 sedimentary, the period of Yaojia formation sedimentary, the period of n1 and n2 sedimentary, the last period of Nenjiang formation, the last period of Mingshui formation and the last period of Paleogene 1pK7（?） EK3R_? .It is thinked that F,Y oil layers are constituted by faults of 4 differential activity rule based on faults activity periods, which are formed in downwarping period, in downfaulted period keeping activity in downwarping period, in downfaulted period keeping activity in downwarping period and reversal period, and in downwarping period keeping activity in reversal period. The 3 type and 4 type of all the 4 types faults are which connect source rock and reservoir, and most of them are boundary faults of belts of fault zone. Based on the establishment of "single-sand" equitime formation framework of F1 oil group in Sanzhao depression, it is thinked that the mainly distribution of channel sands is EN, the faults which connect the source rock and reservoir are mainly SN, and oblique crossing of river and faults is favorable to form fault -lithologic traps. Belts of fault zones are not the main full oil structure. It is the first time to state that oil mainly accumulates in the footwall channel sand of the oil sources faults; belts of fault zones are the fault of "v" shaped "graben", and they are the construction of relatively low position; the oil sources faults are most the boundary faults, belts of fault zones are not the directed zone of oil-gas migration, and oil mainly migrates to the low plates which have Smaller resistance. Wherefore, the footwall channel sand of the oil sources fault are the main enrichment regional, and the "horst" which controlled by the oil sources fault is favorite to accumulate. It is proposd "59 evaluated target zone", which further clarified the next target for exploration, according to the principles of "avoiding fault-zone, in graben or horst which controlled by the oil sources fault" to look for favorable evaluation district.更多还原