Newcastle Australia 1989 (CAR)
On Thursday December 28, 1989, at 10:27 am local time an earthquake of moment magnitude (Mw) 5.4 occurred in the east coast of Australia (New South Wales) at a depth of ~10.5km.
The epicenter (33.95 S, 151.61 W) was located near Boolaroo (a suburb of the city of Lake Macquarie), approximately 15 km WSW of Newcastle’s Central Business District (CBD) and 10 km to the NW of the Lake Macquarie CBD.
The focal mechanism was consistent with a NW striking thrust fault supposedly NE dipping, probably associated with the Hunter-Mooki Thrust Fault System that defines the northern margin of the Sydney Basin.
Despite the moderate magnitude of the mainshock, even for Australian standards, the 1989 Newcastle earthquake was the most damaging and costly earthquake in the Country since European settlement.
The effects were felt over an area of about 200,000 km2, with isolated reports of movement up to 800 km away from Newcastle.
The area sustaining structural damage extended from Newcastle to Liverpool (Sydney) in the south (138 km); Scone in the north-west (145 km); and Gladstone (near Kempsey) in the north (320 km).
The presence of soft alluvial soils, along with the location and condition of particular types of buildings represented a fatal cocktail resulting in extensive damage and loss of human lives.
Badly hit was Newcastle’s CBD and some of its suburbs, built on relatively deep soft alluvial soils, where the maximum assessed intensity was between MM VII and VIII, depending upon who performed the survey. Most of the damage occurred to old and deteriorated unreinforced masonry residential buildings largely built between 1900 and 1950 with some of them dated back to the 1860’s. New buildings (post-1950’s) performed well, this is particularly significant since there where no earthquake design requirements for Newcastle. The exception was the Newcastle Workers Club, where a section built in 1972 collapsed killing 9 people.
The earthquake claimed in total 12 lives plus a thirteenth which died due to earthquake induced shock. About 160 people were injured out of which 100-120 people sustained serious injury needing hospitalization, around 1,000 were made homeless.
In the USGS EXPO-CAT database it is estimated that during this earthquake 206,265 people were exposed to intensity VII or higher, of which about 95% were in urban areas.
Concerning the building stock, about 40,000-50,000 buildings including 25,000-40,000 homes were damaged (most of the damaged occurred to non-structural components) and 300 had to be demolished.
Munich Re estimate an overall economic loss of 1.2 billion USD out of which 670 million USD were insured losses. The overall economic loss represented 0.4% of the Australian GDP in 1989.
The Bureau of Transport Economics in 2001 estimated the economic impact of this earthquake at nearly 3.2 billion USD. This latter estimation seems to overrate the real economic impact.
The Insurance Disaster Response Organisation (IDRO) in 2002 estimated a value for the insured loss of 684 million USD, close to those provided by the Munich Re.
from the EMA database
Incl. 1 death due to shock. 9 died when the roof of the Newcastle Workers Club collapsed, trapping several more that were pulled out alive. 3 died due when trapped under falling awnings in Beaumont Street.
90 buildings were approved for full demolition, 200 for partial demolition. In addition some buildings were demolished without permit in the immediate aftermath of the earthquake.
Out of the 38,000 damaged buildings there were: circa 35,000 homes, 147 schools, and circa 3,000 commercial and other types of buildings.
The EM-DAT database reports 50,000 damaged buildings.
10,000 of the damaged homes had significant damage (costing more than 1,000 Australian $). 42 of the damaged schools had structural damage (Wikipedia article, no reference, visited on Nov. 27, 2013).
300-400 people in the immediate aftermath of the event (Geoscience Australia)
Munich Re reports 1.2 billion US$ overall loss, incl. 670 million US$ in insured losses. The insured losses are not included here, as they are shown under the insured loss field.
In addition, the Bureau of Transport Economics in 2001 estimated the economic impact at 3.175 billion US$ (4 billion Au$) of which 795 million US$ (1 billion Au$) were insured losses. This estimation probably overrates the real damage (Walker G.: Comparison of the Impacts of Cyclone Tracy and the Newcastle Earthquake on the Australian Building and Insurance Industries. 2009 Australian Earthquake Engineering Conference).
The Bureau of Transport Economics in 2001 estimated the insured losses at 1 billion Au$ (795 million US$).
It refers to buildings in the affected region. In addition T.D. Jones, G. Fulford, N. Corby, J. Schneider, M. Edwards (2003), Probabilistic earthquake risk assessment of Newcastle and Lake Macquarie, Australia: Part 2 – Earthquake vulnerability and risk. Pacific Conference on Earthquake Engineering, Christchurch, estimate 120,000 buildings in the affected region.