摘要
本文通过岩心观察、气体孔隙度、渗透率测定，对该区域Jia组岩心进行了物性分析；通过铸体薄片、普通薄片、扫描电镜及X射线衍等手段对储层岩石学特征、孔隙微观特征、粘土矿物微观特征进行了分析；使用压汞手段对储层岩心孔喉结构特征进行了分析。开展变围压与变内压对照实验、储层敏感性评价实验，针对该区域致密储层的特性，从多个角度对其应力敏致敏机理展开了研究，开展了压汞及应力敏感性对照实验，人工造缝样品与基质样品应力敏对比实验，裂缝充填与不充填、不同充填物进行充填对比实验、不同连通性应力敏对比实验、应力敏多次加载实验以及不同含水饱和度下的应力敏对比实验。本文最终得出如下结论认识：
1.变内压与变围压的实验方法均能一定程度上反映出储层受应力敏损害的情况，但考虑到研究区域储层结构复杂多为低孔渗地层故选择变内压的实验方式更好的模拟实际地层受净应力发生应力敏损害的情况。
2.研究区域平均损害率高于85%，属于强应力敏。从平面上看，西部中部井区表现出强应力敏，MN井区相对较弱表现出中等偏弱至中等偏强。三个小层有细微差异，但整体表现仍为强应力敏；纵向上看，除开MN井区J1a1小层到J1a2小层有减弱趋势，其余井区整体表现出强应力敏损害且最大损害率变化不大。故储层整体上表现强应力敏，且中部井区表现出中等偏强到强不可逆损害率。
3．研究区域内应力敏损害曲线大致分为三种类型：
中速应力敏损害，同时伴随着强不可逆损害；快速应力敏损害，同时伴随着弱不可逆损害；中速应力损害，同时伴随着中等不可逆损害。
4．对应力敏损害机理的研究主要在孔喉因素、裂缝因素、多次加载因素、含水饱和度因素等，通过实验结合地质资料发现导致研究区域应力敏强的主要因素是微孔隙发育和微裂缝发育，因此本文主要在孔喉因素与裂缝因素这两方面做双重介质研究损害机理，从而解释了产生三种类型应力敏损害曲线的原因。
5.致密砂岩中裂缝存在时应力敏十分严重，因此，在现场生产开发过程中，应尽量避免采用衰竭式开采，并及时补充地层能量，防止因净应力增大而导致储层渗透性急剧下降而导致开发过程中的减产甚至不出。同时避免储层压力下降导致储层内部分裂缝闭合，造成储层内裂缝连通性下降，从而导
致储层渗透率的急剧下降，由于裂缝连通性越好，应力敏感性越强，所以应保持层内压力相对稳定，避免连通性好的区域产生强应力敏感性导致储层物性变差；同时考虑应力敏影响，在试产过程中不建议采用大压差，同时为减轻或避免含水饱和度升高使致密砂岩应力敏感性变强，应注意减少钻完井液在钻完井过程中的滤失，或者采用氮气钻井等钻井技术。
6．基于以上情况本文给出具体井区实际建议：（微）裂缝发育的井(如迪探1)因压降初期应力损害快速，不可逆损害较小，可采取先衰竭（临界压力6.6MPa）开采，晚期补充地层能量的保护措施以提高采收率；（微）孔隙发育为主的井(如迪北102、吐孜4、吐孜2、吐东2、克孜1)虽初期应力敏损害速度较小，但不可逆损害较大（38.86%），不宜降压开采，需早期补充地层能量的保护措施；（微）裂缝和（微）孔隙发育均衡的井(如依深4、依南2、依南4、依南5)因压降初期应力损害速度和不可逆损害程度中等，可采取先降压（原始地层压力20%）开采，中期补充地层能量的保护措施。
关键词：特低渗致密储层，敏感性规律，应力敏机理，保护措施，实验评价
Abstract
In this paper,the physical properties of the Jia Formation core in this area were analyzed through core obrvation,gas porosity,and permeability measurement;the petrological characteristics and pore microscopic characteristics of the rervoir were determined by means of casting thin slices,ordinary thin slices,scanning electron microscopy,and X-ray diffraction.3.The microscopic characteristics of clay minerals were analyzed;the structure characteristics of rervoir core pore throat were analyzed by means of mercury intrusion. Conducted experiments of variable confining pressure and variable internal pressure,and evaluation experiments of rervoir nsitivity.Bad on
the characteristics of the tight rervoir in this area,the mechanism of stress nsitivity and nsitization was studied from multiple angles,and mercury intrusion and stress nsitivity were developed.Contrast experiment,stress-nsitivity comparison experiment of artificially-produced samples and matrix samples,filling and non-filling of cracks,comparison experiments of filling with different fillers, comparison experiments of different connectivity stress-nsitivity,stress-nsitive multiple loading experiments and different water saturation Stress nsitive contrast experiment.This article finally reached the following conclusions:
销售培训师
中国人民大学研究生院1.The experimental methods of variable internal pressure and variable confining pressure can reflect the stress nsitive damage of the rervoir to a certain extent,but considering the complexity of the rervoir structure in the study area is mostly low porosity and permeability formation,the experiment of variable internal pressure is lected The method better simulates the situation where the actual formation is subjected to stress-nsitive damage due to the net stress.
2.The average damage rate in the study area is higher than85%,which is a strong stress-nsitive.Viewed from the plane,the well area in the central western region shows strong stress nsitivity,and the relatively weak MN well area shows moderately weak to moderately strong.There are slight differences in the three small layers,but the overall performance is still highly stress-nsiti
ve; longitudinally,except for the J1a1layer to the J1a2layer in the MN well area,there is a weakening trend.Has not changed much.Therefore,the rervoir as a whole shows strong stress nsitivity,and the central well area shows a moderate to strong to strong irreversible damage rate.
3.There are three types of stress-nsitive damage curves in the study area:
show是什么意思Medium-speed stress-nsitive damage is accompanied by strong irreversible damage;rapid stress-nsitive damage is accompanied by weak irreversible
damage;medium-speed stress damage is accompanied by moderate irreversible damage.
4.The rearch on the mechanism of stress-nsitive damage is mainly on the factors of pore throat,fracture,multiple loading and water saturation,etc.The main factors leading to the stress nsitivity in the study area are micropore development and microfracture development through experiments and geological data. Therefore,this paper mainly studies the damage mechanism of dual media in the two aspects of pore throat factor and crack factor,thus explaining the reasons for generating three types of stress-nsitive damage curves.
5.The stress nsitivity is very rious when there are cracks in the tight sandstone.Therefore,in the
process of on-site production and development, exhaustive mining should be avoided as much as possible,and the formation energy should be replenished in time to prevent the sharp decrea of rervoir permeability due to the increa of net stress This has led to a reduction in production during the development process.At the same time,avoiding the decrea of rervoir pressure leads to the closure of some fractures in the rervoir, resulting in the decline of fracture connectivity in the rervoir,resulting in a sharp decline in rervoir permeability.The better the fracture connectivity,the stronger the stress nsitivity,so the layer should be maintained The internal pressure is relatively stable,avoiding strong stress nsitivity in well-connected areas and resulting in poor physical properties of the rervoir;at the same time considering the effect of stress nsitivity,it is not recommended to u a large pressure difference during the trial production process,and to reduce or avoid the increa in water saturation The high makes the stress nsitivity of tight sandstone stronger, and attention should be paid to reducing the filtration loss of drilling and completion fluid during drilling and completion,or using drilling techniques such as nitrogen drilling.
牛仔裤的夏天电影6.Bad on the above situation,this article gives practical suggestions for specific well areas:(micro)fractured wells(such as Ditan1)due to rapid pressure damage in the early stage of pressure drop,irreversible damage is small,you can take the first failure(critical pressure6.6MPa)mining,The pr
香辣土豆片的做法otective measures to supplement the formation energy in the later period to improve the recovery factor; (micro)pore development-bad wells(such as Dibei102,Tuzi4,Tuzi2,Tudong 2,Kezi1)although the initial stress-nsitive damage rate Small but irreversible damage(38.86%)is not suitable for decompression mining,and early protection measures for supplementing formation energy are needed;wells with(micro)
fractures and(micro)pores are well-balanced(eg Yishen4,Yinan2,Yinan4, Yinan5)Due to the moderate stress damage speed and irreversible damage in the initial stage of pressure drop,the first step of decompression(original formation pressure of20%)can be adopted for exploitation,and the protection measures of supplementing formation energy in the medium term.
画板图片静脉采血检查什么Key words：Ultra-low permeability tight rervoir,nsitivity law,stress nsitivity mechanism,protection measures,experimental evaluation五大人格
