A 6.9 magnitude at the depth of 10 kilometres and was located 279km southeast of the Loyalty Islands around 8am local time.
A second 4.5 magnitude earthquake struck about an hour and a half later, 263km southeast of the Loyalty Islands.
No tsunami alert has been launched and no injuries or damage has been reported.
The first earthquake was originally reported to be a 6.7 magnitude earthquake but the USGS upgraded it to a 6.9 not long after.
