Abstract.A team of scientists from New Zealand and Indonesia undertook a reconnaissance mission to the South Java area affected by the tsunami of 17 July 2006. The team used GPS-based surveying equipment to measure ground profiles and inundation depths along 17 transects across affected areas near the port city of Cilacap and the resort town of Pangandaran. The purpose of the work was to acquire data for calibration of models used to estimate tsunami inundations, casualty rates and damage levels. Additional information was gathered from interviews with eyewitnesses.The degree of damage observed was diverse, being primarily dependant on water depth and the building construction type. Water depths were typically 2 to 4 m where housing was seriously damaged. Damage levels ranged from total for older brick houses, to about 50% for newer buildings with rudimentary reinforced-concrete beams and columns, to 5-20% for engineered residential houses and multi-storey hotels with heavier RC columns. "Punchout" of weak brick walls was widespread. Despite various natural warning signs very few people were alerted to the impending tsunami. Hence, the death toll was significant, with average death and injury rates both being about 10% of the people exposed, for water depths of about 3 m.

Lead-extrusion dampers are energy absorbing devices that have been designed to provide damping for seismic isolation systems. One type, called the constricted tube damper, has been manufactured for several applications in New Zealand. High manufacturing costs and some performance considerations associated with the damper led to consideration of an alternative design known as the bulged shaft damper. This report describes tests carried out on bulged shaft dampers of two sizes, 100kN and 700kN yielded force. Results show that the bulged shaft design of damper can be expected to perform well during major seismic events, including mainshock/aftershock sequences.

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Fires after earthquakes sometimes develop into conflagrations resulting in widespread losses of life and property. A geographic information system (GIS) model linked to property and valuation data is shown to be an appropriate tool for estimating urban fire losses. One approach uses a static buffering technique to define potential burnout zones that are sampled randomly to give estimates of losses. The other uses a dynamic cellular automaton technique for determining both the rate and extent of fire-spread in response to a wide range of factors including wind, radiation, sparking, branding, building separations and building claddings. The dynamic approach uses a set of 'rules' based on fire physics modified by historical data. The model runs in real time for single ignitions. The static method is used to estimate losses assuming a 12m separation will prevent fire spread All buildings are assumed combustible (upper bound case). The dynamic model assuming fire can not spread to buildings with non-combustible claddings and areas of vegetation are not flammable (lower bound case).

A combination of weak-motion velocity data from seismographs and strong-motion acceleration data from accelerographs has been used to model the attenuation of peak ground acceleration (PGA) in New Zealand earthquakes. The resulting model extends the PGA attenuation model of Zhao, Dowrick and McVerry [30] to include the variability of rock strength, and also describes the unusually high attenuation in the volcanic zone of the North Island of New Zealand. Strong-rock sites were found to experience lower PGAs than either weak rock or soil sites for magnitudes below Mw 7, and the apparent degree of amplification on going from strong rock to weak rock or soil decreased as the magnitude increased from Mw 5 to Mw 7. At magnitude 7 the PGAs were very similar for all site classes for source distances up to 100 km. When extrapolated to magnitudes beyond the maximum of the data, Mw 7.4, the model predicted that PGAs for strong rock sites were greater than for weak rock or soil sites. The so-called "whole Taupo Volcanic Zone" was found to provide a good boundary for the zone of high attenuation in the volcanic region of the North Island. The high attenuation was successfully modelled as a simple function of the length of travel path through the zone of high attenuation. Over the effective maximum volcanic path length of about 70 km the extra attenuation resulted in a factor of ten reduction in PGA compared with non-volcanic paths of the same length.