Delineating spring recharge areas inferred from morphological, lithological, and hydrological datasets on Quaternary volcanic landscapes at the southern flank of Rinjani Volcano, Lombok Island, Indonesia

Springs are a vital source of water supply in Quaternary volcanic environments, such as Rinjani Volcano on Lombok Island, and yet little is known about their emergence and recharge areas. Knowledge of spring recharge area can substantially support further spring analysis and management. This study was performed in two spring zones on the southern flank of Rinjani Volcano. It combined the available morphological, lithological, and hydrological datasets to build a conceptual model of the spring recharge areas. According to the analysis results, the conceptual model allowed to describe the flow medium, the aquifer type, and the characteristics of the flow system. The local morphology controlled the direction and gradient of groundwater flow to the springs. The analysis also revealed that the spring water in the study area was meteoric water, which mainly came from rainwater infiltration. Therefore, the boundaries of the spring recharge areas were represented by the morphological divides.