The diffusive leakage rate (DLR) of brine from a finite fractured aquifer into intact overlying and underlying layers during geosequestration of carbon dioxide is modeled using a two-dimensional radial domain. To handle the interaction between aquifer and caprock or overlying layer (underlying layer), continuities of pressures and fluid fluxes are taken into account at the aquifer-caprock interface. In order to solve this problem, Laplace transform and finite Hankel transform are adopted. The early-time and late-time solutions for DLR of brine from a double-porosity aquifer are also examined using the developed general solution. The solutions are used to analyze DLR from the fractured aquifer into overlying formation and the average pressures in the fractured aquifer and the caprock during injection and post injection periods. Variations of DLR and the average pressures in the fractured aquifer and the caprock with the double-porosity parameters are characterized. It is shown that DLR of brine and the average pressures in the aquifer and the caprock are sensitive to double-porosity parameters during CO₂ injection when ratio of the horizontal fracture to the caprock permeabilities (k_fh1D) is small. However, they remain practically insensitive to double-porosity parameters for a large k_fh1D. The results also confirm that DLR of brine reaches to a fixed pseudo-steady state value at late times during CO₂ injection. In addition, the post injection DLR for low to moderate values of k_fh1D is found to be negligible while for high value of k_fh1D DLR is more evident. These results find applications in geological storage of CO₂ in fractured saline aquifers.

使用二维径向域对二氧化碳地质封存期间从有限裂隙含水层到完整的上覆层和下覆层的盐水的扩散泄漏率（DLR）进行建模。为了处理含水层与盖层或上覆层（下层）之间的相互作用，在含水层-盖层界面处要考虑压力和流体通量的连续性。为了解决这个问题，采用了拉普拉斯变换和有限汉克尔变换。还使用开发的通用解决方案检查了双孔含水层中盐水的DLR的早期和晚期解决方案。该解决方案可用于分析注入后和注入后从裂缝性含水层到上覆地层的DLR以及裂缝性含水层和盖层中的平均压力。用双孔隙度参数表征了DLR的变化以及裂隙含水层和盖层中平均压力的变化。结果表明，在CO过程中，盐水的DLR以及含水层和盖层中的平均压力对双孔隙度参数敏感。当水平裂缝与盖层渗透率之比（k _{fh 1 D}）较小时进行_第二次注入。然而，对于大的k _{fh 1 D}，它们实际上对双孔隙率参数不敏感。结果还证实盐水的DLR在注入CO _2的后期达到了固定的伪稳态值。另外，发现对于k _{fh 1 D的}低到中等值的后注入DLR可以忽略不计，而对于k _{fh 1 D} DLR的高值则更明显。这些结果发现了在CO _2的地质存储中的应用。 在破裂的盐水层中。