缝洞型储层随钻测井自适应有限元法数值模拟

Numerical simulation of the logging-while-drilling for fracturevuggy reservoirs using adaptive FEM

缝洞型碳酸盐岩储层具有强烈的非均质性及储集空间预测难度大的特点,利用随钻电阻率测井方法对缝洞进行准确识别和划分,是当前研究的热点问题.利用一种先进的高精度自适应有限元方法和几何精确的曲边单元造型技术可以模拟缝洞型储层的随钻测井响应.本文通过研究仪器在不同半径缝洞的模拟测井响应及缝洞填充与坍塌导致的机械填充对测井结果的影响,给出了用于识别缝洞大小和填充程度的缝洞型储层的测井响应特征.研究结果为缝洞型碳酸盐岩储层的识别与划分提供了理论依据.

Fracture-vuggy carbonate reservoir are characterized by heterogeneity, which makes reservoir space prediction difficult. The use of resistivity logging-while-drilling （LWD） for accurate identification and classification of the fracture-vuggy, is currently a research focus. Using an advanced high precision adaptive finite element method and geometric precision curved edge element can calculate fracture-vuggy reservoir LWD response. In this paper, we study the impacts on log response of fracture-vuggy reservoir models with different size fracture-vuggy radius and different degree of mechanical filling caused by fill and collapse of fracture-vuggy, determine the log characteristics of identify fracture-vuggy size and degree of fracture-vuggy filling. Results provide a theoretical basis for the identification and division of the fracture-vuggy carbonate reservoir.