Liquefaction during historic earthquakes in New Zealand
Abstract
The literature has been searched for accounts of liquefaction during historic earthquakes in New Zealand. About 30 fairly clear cases of liquefaction were found in 10 earthquakes since 1843. The 1848 Marlborough and the 1931 Napier earthquakes appear to have caused the most widespread occurrences. Both were large earthquakes in regions with extensive saturated fine-grained alluvial deposits. Since liquefaction has only recently been recognised as a distinct phenomenon, evidence of its occurrence was not expressly searched for in early investigations, and it is possible that many instances have gone unrecorded. Therefore it is likely that liquefaction has been more pervasive than the 30 clear cases suggest. With the exception of the M ≥ 6, 1895 Taupo earthquake which liquefied a pumice soil, all have occurred in earthquakes with magnitudes of at least 6.9. However, some larger earthquakes, most notably the 1929, M = 7.8 Murchison earthquake, have produced no records of liquefaction that we could find. Given the uncertainties of early epicentral locations, the New Zealand cases are consistent with the expression of Kuribayashi and Tatsuoka (1975) for distance to the farthest site of liquefaction, although the number of cases is too small to establish the correctness of the relationship under New Zealand conditions.