【作者】 季宗镇；

【导师】 戴俊生；

【作者基本信息】 中国石油大学 ， 地质资源与地质工程， 2010， 博士

【摘要】 本论文在岩心裂缝描述、压裂计算、岩心声速试验的基础上,综合运用数学、力学、地质学等多种方法原理建立了地应力与构造裂缝参数之间的定量关系,并对江苏油田卞东、闵桥、杨家坝地区阜宁组储层地应力分布、构造裂缝参数进行了研究。通过对卞闵杨地区42口取心井岩心裂缝描述发现,卞闵杨地区阜宁组主要发育有近东西向及北东东、北西西向高角度缝、垂直缝。宏观裂缝真实开度主要分布在0.2-0.6mm之间,裂缝线密度较小,井间裂缝发育程度变化较大。构造裂缝多为全充填缝,方解石充填,部分为沥青质以及泥质充填。张性缝、剪性缝及张剪性缝都有发育。分析古构造演化史认阜宁组晚期为主要造缝期。开展储层构造裂缝定量研究的关键及难点在于能否建立合理的地应力与裂缝参数之间的定量关系。从裂缝形成的微观原理出发,选用库伦-莫尔准则及格里菲斯准则作为岩石剪性及张性破裂判据,以岩石力学、断裂力学中应变能、表面能理论为基础,借助于表征单元体及裂缝平板渗流模型分别研究了三向挤压应力状态及有张应力存在情况下地应力与构造裂缝参数之间的定量关系。利用地层倾角测井资料及取心层位构造图对岩心进行定向,然后利用声速法、水力压裂资料计算了现今水平地应力并确定了应力方向。开展古今应力场数值模拟,获得了卞闵杨地区的地应力分布,将应力场模拟结果与压裂井计算数据对比发现,地应力模拟具有较高精度。研究表明:卞闵杨地区构造高部位为现今地应力低值区,地应力与地层埋深呈线性比列关系;断层对于地应力具有明显的控制作用,古应力场中断层带附近应力相对集中,现今应力场断层带附近地应力分布与之相反;卞东、闵桥、杨家坝地区地应力方向一致,最小主应力都为近南北向。将地应力场模拟结果导入裂缝参数计算模型,对卞闵杨地区阜宁组储层裂缝参数进行了预测,并利用岩心裂缝统计数据对裂缝预测成果进行了验证。研究发现,卞东地区中部b4-3、b7-2井附近,闵桥南部m35断块及杨家坝地区南部断层上升盘y11-5、y22-1井附近为裂缝发育密集区,裂缝孔渗性能最好。卞闵杨地区裂缝发育具有以下特征:古应力场中断层附近的拉张应力高值区为裂缝发育密集区;构造高部位现今裂缝开度较大,孔渗性能较好;裂缝发育优势方向决定了卞闵杨地区现今裂缝东西向、铅直向渗透率明显高于南北向渗透率。更多还原

【Abstract】 On the basis of core fracture description, hydraulic cracking calculation and sound speed experiment, the relationship between crustal stress and parameters of tectonic fracture was confirmed using mathematics, mechanics and geology method. This dissertation analyzed the distribution of crustal stress and tectonic fracture of Funing Group in Biandong, Minqiao and Yangjiaba region.42 wells core fracture statistics shows that Funing Group of BMY mainly developed high angle fractures and vertical fractures with trend of nearly WE and NEE, NWW. Macrofractures mainly distributed in 0.2-0.6mm. The fracture linear density is small and changed greatly interwell. Most of the tectonic fractures were wholly filled with calcite and the rest of them were filled with asphalt and slime. Tectonic fractures appear in several forms such as tension fracture, shear fracture and tension-shear fracture. The structural evolution analysis shows the Late Funing Period is the important fracture period.The quantitative relationship between crustal stress and parameters of tectonic fracture is the key to the reservoir fracture prediction. On the basis of strain energy, surface energy in rock and fracturing mechanics theory, the relationship was confirmed using the represent element volume and flat seepage model. The Coulomb-Mohr principle was applied to the examination of shear fracture, while Griffith principle was taken as the examination of tension fracture.Diplog and structure map were used to core orientation. Penetrating fluid method and sound speed experiment were used to confirm the value and orientation of the current crustal stress. The stress distribution of BMY area was confirmed by ancient and current stress field numerical simulation. The comparison between simulation and hydraulic cracking data shows that crustal stress numerical simulation is accurate. The high position of BMY area is the current crustal stress low-value area. The relationship between crustal stress and formation depth is linear. Faults for the control of stress have a significant role. Stress concentration occurred near the fault zone in the paleo stress field while the current stress distribution reverse. Biandong, Minqiao and Yangjiaba have the unified direction of stress. The minimum principal stress is nearly north-south. The crustal stress simulation data were imported to fracture parameters model, and the predicted parameters were verified by the core fracture statistical data. The result shows that, the central area of Biandong, m35 block of south Minqiao and the south fault upcast of Yangjiaba were the intensive fracture areas in which the fracture porosity and permeability are highest. Tectonic fractures of BMY area have the following characteristics: The high value areas of tensile stress in the paleo-stress field are the fracture-intensive areas; Fractures in high part have greater aperture and better poroperm characteristics; The dominant fracture strike decides the current east-west and vertical component of permeability are significantly higher than the north-south component.更多还原