[[:file:predicting-reservoir-system-quality-and-performance_fig9-49.png|Figure 2]] is an Eh–pH diagram, showing the approximate distribution of various types of subsurface fluids. | [[:file:predicting-reservoir-system-quality-and-performance_fig9-49.png|Figure 2]] is an Eh–pH diagram, showing the approximate distribution of various types of subsurface fluids. |