Review on status of groundwater database and application prospect in deep-time digital earth plan

[Display omitted] •Groundwater database and relevant big data research investigated.•The gap between current groundwater database and demand of DDE plan summarized.•An improved framework of groundwater database for DDE plan proposed. Groundwater is an important water resource. The total amount of active groundwater in a hydrological cycle is about 3.5 times that of the total amount of surface water. The information in the deep groundwater records the material exchange and dynamics in the earth’s evolution, which is an important aspect of the Deep-Time Digital Earth (DDE) plan. In recent years, scientists have discussed the distribution of transboundary aquifers and the environmental significance of groundwater resources through groundwater databases established by international organizations, such as the Global Groundwater Information System and the chronicles consortium, and national institutes, such as national geological surveys. The application of the groundwater database in the DDE plan, however, has been limited by the management, interactivity, and monitoring method of the groundwater data. The ability to further integrate data that are private and scattered across research institutions and individuals, while establishing an open, unified, and shared groundwater data platform, is essential to enhance our understanding of groundwater, ranging from shallow to deep water, which is a goal of the DDE plan. In this study, we introduced the current situation of groundwater database operations in domestic and international research and provided frontier research with groundwater big data. Considering the related objectives of the DDE plan and the limitations of existing groundwater databases, we proposed an improvement plan and new prospects for applying groundwater databases in the research of the deep earth.