Global phases are seismic waves that travel through the earth’s core before emerging at the surface. Traditionally, global phases are used to obtain subsurface information up to 1 Hz. A recent study, however, found that signal present in the coda of strong, distant earthquakes contains higher frequencies. Quantitative analysis of the coda of earthquakes, of at least mag-nitude 6, shows that frequencies of, on average, 3 Hz can be found, with the most promising results coming from P- and PKIKP-phases. By autocorrelating the coda of these phases an estimate of the zero-offset reflection response below a seismic station can be retrieved. The method allows to successfully delineate basins in both Argentina and the United States. Even higher frequencies, up to 8 Hz, are used at specific stations, that have been active for an extended period of time (≥ 8 years). Again the method succeeds in retrieving structural information below these stations. The results of both studies are confirmed by existing lit-erature as well as Ambient Noise Seismic Interferometry (ANSI) studies. ANSI is a method, which retrieves the reflection response below a station by applying seismic interferometry to ambient noise. Advantages are that the method is computationally cheap and fast and that it is a passive measurement thus requiring low-effort. A disadvantage, however, is the unpredictability of earthquakes, which means that the exact duration the stations have to be active is unknown. Instead, the station will have to record over a prolonged amount of time, during which suitable earthquakes should occur. Research into the upper crustal structure, in particular, may ben-efit from the method. For example, the depth of a sedimentary basin can be discovered and imaged using this method. This gives important constraints, e.g. for geothermal prospecting.