Fig. 1: Hydrogeological settings and station locations in the study area.
From: Space-time monitoring of groundwater fluctuations with passive seismic interferometry
a Groundwater basins near Los Angeles, California (adjudicated to different local water departments). Primary basins studied in this paper include the San Gabriel Basin, the Los Angeles (LA) Central Basin, the Santa Ana Basin, and the LA West Coast Basin. b The unconfined (forebay) and confined zones in LA Central and Santa Ana basins. The forebay boundary is estimated by the Orange County Water District (OCWD)45 and the Water Replenishment District (WRD) of Southern California46. Confined to semi-confined conditions also exist in the San Gabriel Basin. c Station locations. Yellow triangles denote the broadband, 3-component seismic stations in the CI network operated by the Southern California Earthquake Data Center (SCEDC) available from 2000 to 2020. The blue circle denotes the groundwater monitoring well GGM-1/MP1 operated by OCWD, from which the hydraulic head data are shown in Fig. 2b. The violet diamond denotes the meteorological station ANA at which the precipitation record is shown in Fig. 2a.
