SBIR Phase II: Inversion of Geophysical Measurements for Fracture Geometry

这个小企业创新研究（SBIR）第二阶段项目考虑了一种用于检测和量化岩石中天然裂缝系统的创新方法。 裂缝系统的几何形状控制着许多油气储层和含水层的渗透性。 石油和天然气以及环境应用都需要新的工具和技术来量化裂缝几何形状，从而可以预测渗透率。 在第一阶段的研究中，开发了一种反演方法，用于从不同的地球物理测量中获得裂缝几何形状。这是通过将裂缝几何形状与各种各向异性、应力相关属性（包括渗透率、电导率和地震速度）以及最大熵正则化标准相结合的正演模型来实现的。结果表明，相对少量的地球物理测量可用于反演裂缝几何形状的统计描述，具有一定的预测能力。 根据这一原理证明，在第二阶段，该方法现在将变成一种交互式工具，用于研究和理解石油和天然气以及环境应用的断裂系统行为。为了实现这一目标，将完善正向模型，针对这一特定问题调整反演算法，并使用案例研究验证算法。 通过为储层流体流动模拟器定义真实的输入参数，这种新能力可能会为勘探、开发和储层动态活动提供许多改进。开发新的创新和具有成本效益的勘探和储层模拟技术符合我们的国家利益，这些技术将延长石油和天然气储层的使用寿命，并延长在我国生产具有价格竞争力的石油和天然气的时间。 L

This Small Business Innovation Research (SBIR) Phase II project considers an innovative method for detecting and quantifying natural fracture systems in rock. The geometry of the fracture system controls the permeability of many oil and gas reservoirs and aquifers. Both oil and gas and environmental applications require new tools and techniques to quantify the fracture geometry, thus allowing prediction of permeability. During the Phase I research an inverse method was developed for fracture geometry from diverse geophysical measurements. This was accomplished by combining forward models relating fracture geometry to various anisotropic, stress-dependent properties including permeability, electrical conductivity, and seismic velocity with a maximum entropy regularization criterion. It was demonstrated that a relatively small number of geophysical measurements could be used to invert for a statistical description of the fracture geometry with some predictive power. Following this proof of principle, in Phase II, this method will now be turned into an interactive tool for studying and understanding fracture system behavior for oil and gas and environmental applications. To accomplish this, the forward models will be refined, the inversion algorithm will be tuned for this specific problem, and the algorithms will be validated using case studies. This new capability will likely provide many improvements to exploration, development, and reservoir performance activities by defining realistic input parameters for reservoir fluid flow simulators. It is in our national interest to develop new innovative and cost effective exploration and reservoir simulation technologies which will extend the useful lifetime of oil and gas reservoirs and extending the period of time that competitively priced oil and natural gas can be produced in this country. l