Aftershocks rattle NZ after 6.6 quake KIDS at a school in New Zealand's capital Wellington were learning what to do in an earthquake just as a magnitude 6.6 quake struck, while Marlborough's mayor asked churchgoers to pray as he sheltered with them under a table. How spooky was that?! We were still under the desks for our practice evacuation and the earth started shaking! Clyde Quay School wrote on its Facebook page. But all is well. And that is what everyone is saying. Dubbed the Lake Grassmere earthquake, it struck at 2.31pm (1231 AEST) on Friday 10km southeast of the Marlborough town of Seddon at a depth of 8km, followed by a series of scary aftershocks. Insurers reported only minor damage and hospitals treated a few people for minor injuries. Marlborough district council mayor Alistair Sowman was meeting with members of churches on the top floor of the council building when the strongest quake he has ever felt struck. "I suggested under the table they might like to say a few words," he told AAP. We thought we would have major damage, but there's not. Goods fell off supermarket shelves, power was lost, chimneys were damaged and buildings are being checked again. Two bridges on State Highway 1 in Marlborough were closed, and the road between Seddon and Kaikoura was closed after rockfalls. At Riverlands Winery, 250,000 litres of wine was lost down the drain when a wine tank was damaged, according to RadioLive. There were no reports of major damage to buildings in Wellington but police said some houses in Seddon had been damaged. No tsunami was generated. Dozens of aftershocks have since rattled the area with the biggest registering 6.0 striking three hours after the initial quake and a number of others registering more than 5.0. Office workers in Wellington headed home early. Cabinet minister Steven Joyce tweeted: "Lots of aftershocks. Beehive wobbling around like a jelly, but all ok. Three grass fires in Seddon were sparked by fallen power lines. Near Ward, a house had slipped on its piles. Wellington mayor Celia Wade-Brown said there were initial reports of some superficial damage to buildings in the CBD, but there have been no reports of any major damage, nor any serious injuries. A spokesman for Centreport, which lost land into the sea in last month's quake, said there had been no serious damage, but most operations had been suspended while checks were carried out. The Lake Grassmere quake is a strike-slip quake, as was the magnitude 6.5 in the region in July. These occur when faults are vertical or nearly vertical. "We have now had two similarly sized earthquakes with the same sort of characteristics - they are termed a 'doublet'," said Kevin Fenaughty, GeoNet's data centre manager. This is not what we would usually expect.