In the present paper, a fuzzy model of assessment is proposed according the framework of fuzzy mathematical theory to estimate the complexity of rock fractures and geological structures. We established the fuzzy evaluation model and decided a trapezoidal membership function using the fuzzy mathematics. Dataset acquisition is integrated with an advanced technique of coupling multiscale fracture data obtained from both high-resolution satellite imagery and field data. Five parameters were selected, including qualitative and quantitative data from different scales, namely fractal dimension, fracture length, fracture intensity, the intersection angle between fractures and beddings and the fracture density. The weight of each factor is obtained with the principle that the relative value of the complexity index is larger and the weight is significant. This model was applied to the complexity assessment of the southwestern Tunisia. The rank of complexity of each sub-area in the study region is from strong to weak. The result shows that Jebal Orbata and Jebal Chamsi have the strongest complexity due to their position beside the 140 dextral strike-slip Gafsa fault. The east and central zone of the region of investigation has the weakest complexity.

在本文中，根据模糊数学理论的框架，提出了一种模糊评价模型来估计岩石裂缝和地质结构的复杂性。我们建立了模糊评价模型，并利用模糊数学确定了梯形隶属函数。数据集采集与耦合从高分辨率卫星图像和现场数据获得的多尺度裂缝数据的先进技术相结合。选取了5个参数，包括不同尺度的定性和定量数据，即分形维数、裂缝长度、裂缝强度、裂缝与层理的交角和裂缝密度。各因素的权重按照复杂度指标的相对值越大权重显着的原则求得。该模型应用于突尼斯西南部的复杂性评估。研究区域内各分区的复杂程度由强到弱。结果表明，Jebal Orbata 和Jebal Chamsi 由于位于140 右旋走滑Gafsa 断层旁，其复杂性最强。调查区域的东部和中部地区的复杂性最弱。