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In this study we show that time-lapse measurements of a reservoir can be made by noise interferometry of borehole data. We used borehole geophone array data of monitoring well SDM-1 in the Groningen gas field in the Netherlands. The ambient, anthropogenic noise allows accurate determination of the P and S velocity structure ( Zhou & Paulssen, 2017 ), but is not stable enough in time and space to measure temporal travel time variations. With deconvolution interferometry of high-frequency train signals, however, it is possible to detect small travel time decreases of ~0.05 ms (0.1%) over half a year associated with compaction of the reservoir. Moreover, we identified a strong travel time anomaly over a period of 1.5 months that is caused by drilling of a new borehole in the reservoir at ~5 km distance.