ERT在水合物在线监测中的应用:以结融冰过程为例

Application of ERT to Hydrate Monitoring: Take Ice as Substitute

电阻率层析成像技术(ERT)作为一种岩心尺度的可视化测试手段,在天然气水合物成藏-开采过程模拟方面具有广阔的应用前景。目前国内专门针对天然气水合物合成-分解过程进行电阻率层析成像观测的报道较少。本文采用自主研发的天然气水合物电阻率层析成像测试系统,以冰的形成和融解过程为例,探讨了电阻率层析成像技术在天然气水合物可视化观测中的可用性。实验结果表明,电阻率层析成像技术能够实时在线监测沉积物体系中冰的形成和溶解过程,以及该过程中冰在沉积物孔隙中的分布规律。结冰-融冰过程中沉积物体系的电导率分布受温度、孔隙连通性、盐度因素影响,排盐效应对电导率不均匀性分布影响明显。研究结果对进一步开展电阻率层析成像技术在天然气水合物探测方面的应用有一定的参考意义。

As a visual testing method on core-scale,electrical resistivity tomography(ERT)has a promising application in the simulation experiment for gas hydrate accumulation and exploitation.So far,there have been few literatures on natural gas hydrate(NGH)synthesis process using ERT as a tool in this part of the world.Using the NGH ERT test system and taking ice as substitute to observe the process of ice forming and-melting,this paper discussed the application of ERT to gas hydrate visual simulation.The results show that the ERT could efficiently monitor the formation and dissolution of ice within the sediment system as well as the distribution of ice in the pores of sediments.The distribution of the conductivities of the sediment system in the process of ice forming and melting is affected by temperature,pore connectivity and salinity,and desalting has obvious influence on the non-uniform distribution of conductivity.The conclusion of this study is of significance to further application of ERT to NGH test.