A huge earthquake fault line has been found underneath Auckland, New Zealand's largest city. The fault line, just south of the city, is active and could cause a city-destroying earthquake, new research shows. The discovery has also raised questions over a recent decision to exempt Auckland from earthquake building regulations. A study in the New Zealand Journal of Geology and Geophysics shows that the Mangatangi Fault - located 50 kilometres southeast of central Auckland - is active. TRENDING St