Observations of natural fractures in core or image logs typically give limited information on orientation, aperture and intensity. Because of the sparseness of wellbore intersections of fractures, data analysis results in incomplete statistical characterization of the fracture population, leaving interwell characterization almost impossible. Using basic fracture mechanics models and a novel core-testing technique, we propose that the fundamental shape of fracture parameter distributions can be predicted, and that there is a characteristic, quantifiable relationship between fracture length, spacing and aperture. We have performed subcritical fracture growth tests on numerous core samples, using credit card sized specimens, demonstrating the ability to characterize fracture mechanics properties of rock on a bed by bed basis. Using the subcritical index, a parameter that quantifies the relationship between natural fracture propagation velocity and tip loading conditions, we can predict the degree of fracture spacing regularity or clustering for a given reservoir bed. This subcritical parameter, along with information on the number of initial natural flaws in a given rock type, allows us to quantify the expected length distribution of the fractures. Under many conditions, as verified from outcrop data, fracture length is theoretically expected to follow an exponential distribution. Since natural fracture length is typically unobservable in subsurface data, we derive relationships that relate fracture length to aperture and spacing, both more readily measurable quantities. With this information, matrix block size and fracture drainage continuity can be estimated for the purpose of flow simulation in a fractured reservoir.
在岩心或钻井记录图象观测的天然裂缝一般都是有限的关于方位，孔穴和强度的信息。由于井筒交叉口的稀疏裂缝，数据分析在不完全的统计下表征断裂总数，和在离开井间表征的结果几乎是不可能的。使用基本裂缝力学模型和一种新的岩心检测技术，我们建议的基本形状的裂缝参数分布是可以预测的，并有一个特点，断裂长度，间隔和孔径之间的量化关系。我们已测试无数岩芯样品的临界裂缝增长，用信用卡大小的标本，展示了表征不同岩石层位基部上裂缝力学性能的能力。使用临界指数，通过量化天然裂缝传播速度和极限的加载条件关系的参数，我们就可以预测裂缝间距规律性的程度或给定储集层的聚类。这个亚临界参数，随着人数对给定的岩石类型的原始天然裂隙数的资料，让我们可以量化预期的裂缝长度分布。 根据许多条件，并验证了从野外露头资料，断裂长度理论的预想为后续指数分布。由于天然裂缝的长度是典型的在地下数据是不可观的，我们得到相关孔穴的裂缝长度和间隙的关系，都更是随时可衡量的数量。获此信息后，基质块大小及裂缝排驱的连续性可估计为我们探讨流动模拟在裂缝性油藏的目的。
第一句：在岩心资料或成像测井资料中观测的天然裂缝通常只能提供裂缝的方位、开度和破裂强度等有限的信息。
楼主的翻译还需要加强啊，一是在断句上，二是在专业词汇上
