To achieve the RELACS Program's aim of improving the capabilities of the Rabaul Volcanological Observatory to locate and interpret volcano-related earthquake activity near Rabaul, a program of seismic field observation was undertaken in the Rabaul area by a consortium of institutions with significant experience in seismic work, viz AGSO, ANU, and the Universities of Hokkaido and Wisconsin. This Record describes post survey data processing of RELACS field data undertaken at the ANU, the University of Hokkaido and AGSO 1998-99. It also includes CDs of data files containing information on seismic recording stations, seismic shots, some earthquake locations, the arrival times of seismic waves, and seismic record files from stations in the international SUDS format.

A dataset comprising some 260 seismograph and accelerograph records from 67 events of the Burakin 2001-02 earthquake sequence was compiled to develop regional ground-motion models for southwestern Western Australia. Events range in size from moment magnitude 2.3 - M - 4.6. The decay of spectral amplitudes can be approximated by a geometrical spreading coefficient of R-1.05 within 80 km of the source. The associated model for the regional seismic quality factor can be expressed as Q(f) = 290f1.09. These attenuation parameters are subsequently used to evaluate average source parameters for the 67 earthquakes. For the observed magnitude range, data demonstrates a seismic moment (M0) - local magnitude (ML) relation following: log M0 = 1.14 ML + 10.45, where M0 is in N-m. Average corner frequencies for these events do not vary significantly with M0 particularly for events M > 3.0, chiefly ranging between 2-3 Hz. This gives rise to anomalously low stress drops for lower magnitudes (M < 4.0) that increase at larger magnitudes.

One of Australia's most serious natural disasters occurred when an earthquake shook Newcastle in New South Wales, leaving 13 people dead and injuring more than 160. The damage bill has been estimated at around A$4 billion dollars, including an insured loss of over A$1 billion. All the result of just a few seconds of earthquake ground shaking at 10:27am on 28 December 1989 (McCue and others, 1990). The consequences of this moderate earthquake to Newcastle (Pop. 300 000), an industrial city on Australia's east coast, could so easily have been avoided with the hindsight of history and the application of relatively inexpensive earthquake engineering principles.

The southwest corner of Western Australia consists of Protozoic geology with the area undergoing no tectonic activity in the last 40Ma. It has not been glaciated in the last 20Ma and has had a cool dry climate for at least 200ka, thus providing an ideal environment to preserve fault scarps. High resolution DEM data has been used to identify over 50 new features that are thought to be scarps of surface rupturing earthquakes. Half of these scarps have been the subject of some field work with one new feature being fully verified. Using recently developed fault scaling relations the fault length and displacement are used to estimate the magnitude and, in many cases, identifying multiple events. This has been used to generate a neotectonic earthquake catalogue. Non-extended stable continental region (SCR) and extended continental crust (ECC) and have separate catalogues The SCR catalogue is considered to have a magnitude of completeness (Mc) of M6.5 with ~55 earthquakes of M6.5 or greater. The data has typical truncated GR recurrence characteristics, with a slope (b) of 0.9-1.0, between magnitude 6.5 and 6.9, and rapid decrease in recurrence above M6.9. SCR data has an asymptote of M7.2 suggesting a Mmax of M7.1-M7.3. The ECC data has a Mc of M7.2 and has 15 events of this magnitude or greater. The recurrence rapidly decreases above M7.4 with an asymptote of M7.6 suggesting a Mmax of M7.5-M7.7. The large number of SCR events gives us confidence in the proposed Mmax of M7.2.

The Mw 7.1 New Zealand earthquake was the largest earthquake in New Zealand in 60 years and occurred in the sparsely populated Fiordland region of New Zealand. The earthquake caused no deaths and only minor damage in the town of Te Anau, although it was felt through out most of the south island of New Zealand. Surprisingly, it was felt in Sydney, 1800 kilometre away, with some people evacuating buildings. People in Sydney did not feel body or surface waves but felt the T phase from the event. Human perception of a T phase is very rare, with the 1977 Mw8.1 Tonga event being felt in Tahiti 2600 km away (Talandier and Okal 1979), being one of the few well documented instances. The Sydney recording of T phase, whilst larger than the body waves, would still be considered weak motion and not normally felt. I suggest that for someone to have felt this event required the coincident of several factors which enhanced the resulting shaking.

Abstract for Indonesian Geophysics conference (HAGI)

Legacy product - no abstract available

We describe a weighted-average approach for incorporating various types of data (observed peak ground motions and intensities, and estimates from ground motion prediction equations) into the ShakeMap ground motion and intensity mapping framework. This approach represents a fundamental revision of ShakeMap technique, particularly as it pertains to processing ground motion and intensity data. Combining ground motion and intensity data onto composite ShakeMaps proves invaluable for loss calibration of historical events as well as for loss estimation in near-real time applications. In addition, the increased availability of near-real-time macroseismic intensity data, the development of new relationships between intensity and peak ground motions, and new relationships to directly predict intensity from earthquake source information, have facilitated the inclusion of intensity measurements directly into the ShakeMap computations. Our approach allows for the possible combination of all of the following data sources and estimates: 1) nearby observations (ground motion measurements and reported intensities), 2) converted observations from intensity to ground motion (or vice-versa), and 3) estimated peak ground motions from prediction equations (or numerical estimates).

The Indonesia Earthquake Hazard Program (IEHP) is a four-year project aimed at enhancing the capacity of the Government of Indonesia (GoI) to undertake earthquake hazard and risk assessments. The IEHP is a joint collaboration between the Australia-Indonesia Facility for Disaster Reduction (AIFDR), the GoI, Indonesian Universities and Geoscience Australia.

Legacy product - no abstract available