An initial experiment with the continuous gravity monitoring using the gPhone 145 to support hydrology and earthquake studies

Continuous gravity monitoring as geodetic instruments for tidal variation recording has been proving its availability for more applications. The original purpose was to monitor the changes in gravity at one local, which could be correlated to the hydrological variation and geothermal reservoir changes. Most recently explored was its relation to the events of earthquakes. We have been installing the gPhone 145 since 2016 at LIPI Campus in Bandung as a preliminary observation of the instrument. In four years of installation, the gPhone has recorded the relative gravity intermittently, interrupted only by technical problems. Temperature and pressure records indicate the instrument functions properly. However, uneven recording prevented hydrological study, in which we expected to see some changes of the gravity through the years. For earthquakes’ precursor studies, additional samples of events and time-associated gravity anomalies might give more assuring results.