Seismically active faults are key features of the earth, and earthquake-induced carbon dioxide released from natural faults has been detected. But the link between active fault deformation and amounts of carbon dioxide emission remains poorly understood. In this paper we monitor progressive carbon dioxide levels and strain signals from the boreholes in a seismically active fault, and show that the carbon dioxide variations are sensitive to the fault deformation over the same time scale of the observations. Therefore, we preliminarily propose a mass-wave propagation model (e.g., interaction of shock waves with advection-diffusion of mass, namely the gas hammer effect) to physically interpret carbon dioxide variations due to dilation or compaction of fluid paths in the natural fault. Of particular interest is that the penetration of shock waves into the natural fault mechanically influences carbon dioxide migration.