A shallow 4.8 earthquake felt in Wellington Monday night hit the fault-riddled Cook Strait, GNS science says.

Geonet says the short, sharp quake struck at 11.38pm and was centred 15 kilometres south-west of Wellington, at a depth of 13 kilometres.

GNS science advisor Jon Ristau tells Morning Report earthquakes of this size in Cook Strait are not unusual.

"Cook Strait itself is riddled with faults that have been mapped by NIWA so earthquakes in this region are not uncommon at all."

Jon says he felt it in Upper Hutt, though it wasn't strong. People from the Bay of Plenty have reported feeling the quake too.

"But I can imagine people in Wellington probably got a pretty good rattle."

There was a 2.5 magnitude aftershock shortly after the initial quake and a few smaller aftershocks, he says.

More than 17,000 reports were received from people who felt the shake, according to the GeoNet site.

-RNZ.