Improving the knowledge about how hydraulic fracture networks are generated in subsurface shale volumes in unconventional wellbores may be accomplished with various configurations of at least one diagnostic lateral wellbore using at least one diagnostic device disposed in the diagnostic lateral wellbore. By extending diagnostic lateral wellbores from adjacent lateral wellbores and/or separately drilling diagnostic lateral wellbores, and analyzing signals received by diagnostic devices placed in the diagnostic lateral wellbores, knowledge about fracture networks, the parameters that control fracture geometry and reservoir production and how reservoirs react to refracturing techniques may be greatly improved. Additionally, such diagnostic lateral wellbores can provide quicker location of sweet-spot horizons in reservoirs.