An earthquake measuring 5.6 on the Richter scale shook New Zealand's South Island at 8.15 Thursday morning and was felt across Cook Strait in the capital Wellington, according to DPA. The quake was centred near the geothermal resort of Hanmer Springs, about 100 kilometres south of Nelson and was centred 70 kilometres below Earth's surface, seismologists at GNS Science reported. There were no immediate reports of injury or damage.