Seismometers were deployed at the Apollo 12, 14, 15, and 16 landing sites. By analyzing the data from them, researchers were able to locate the hypocenters of numerous moonquakes.  A hypocenter is the subsurface location where a moonquake/earthquake originates. Most of these hypocenters were deep into the Moon, distributed between 550- and 1400-km depths (Fig. 4).  For comparison, on Earth, earthquakes occur in depths 700-km and shallower.  If you also consider the fact that the radius of the Moon is only 1/4 (~6370 km vs. 1,737 km), you see that moonquakes are happening a lot closer to the Moon’s core than earthquakes to the Earth’s core. 

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          There are about 100 subsurface localities on the nearside hemisphere of the Moon that repeatedly generate moonquakes.  These localities are called ‘moonquake nests’ or ‘moonquake clusters’.  There probably are moonquake nests in the far side hemisphere, too, but we do not know, because all of the Apollo seismometers were placed on the near side and so detected much fewer moonquakes in the far side.