2011 Tōhoku earthquake and tsunami additional power, because TEP's power plants were also damaged in the earthquake. Kansai Electric Power Company (Kepco) cannot share electricity, because its system operates at 60 hertz, whereas TEPCO and TEP operate their systems at 50 hertz; this is due to early industrial and infrastructure development in the 1880s that left Japan without a unified national power grid. Two substations, one in Shizuoka Prefecture and one in Nagano Prefecture, were able to convert between frequencies and transfer electricity from Kansai to Kanto and Tōhoku, but their capacity to do so is limited to 1 GW. With the damage to so
June 2011 Christchurch earthquake June 2011 Christchurch earthquake The June 2011 Christchurch earthquake was a shallow magnitude 6.3 M earthquake that occurred on 13 June 2011 at 14:20 NZST (02:20 UTC). It was centred at a depth of 6 km (3.8 mi), about 10 km (6 mi) from Christchurch, which had previously been devastated by another magnitude 6.3 M earthquake in February 2011. The June quake was preceded by a magnitude 5.9 M tremor that struck the region at a slightly deeper 8.9 km (5.5 mi). The United States Geological Survey reported a magnitude of 6.0 M at a depth of about 9 km