Fig. 1From: Monitoring of a geothermal reservoir by hybrid gravimetry; feasibility study applied to the Soultz-sous-Forêts and Rittershoffen sites in the Rhine grabenThe concept of hybrid gravimetry to investigate an underground reservoir (a) with the combination of superconducting gravimeter (SG) (b), absolute gravimeter AG (c), and relative spring meter RG (d) (adapted from Sugihara et al. 2013)Back to article page