Eric BuriEric BuriPort Moresby Geophysical Observatory

Geohazards DivisionDepartment of Mineral Policy & Geohazards Management

DMPGM Mission & Vision

To improve the quality of life and safety of all people in PNG through effective Mineral Policies and reduction of Geological Risks

To establish a state of the art Geohazards Management System to minimize property damage and loss of life

04/20/23 2

Seismicity of the Earth 1900-2012(M7.5+)

New Guinea Region

Use of GIS in Enhancing Operation

Catogorising earthquakes appropriately

Make it easier to be understood by the general public when in graphic format

Useful for planning purposesUseful for public awareness on earthquakes and tsunamis

New Guinea Region SeismicityNew Guinea Region Seismicity

Seismicity of the PNG region in the period 1900 to 2012.Black circle denote depth range of 400km and moregreen stars denote depths of 250-399kmyellow diamonds denote depth range 100-249km blue triangles denote 40-99km Red circles denote shallow depths 0-39km

Figure 1a. Tectonic configuration and seismicity of PNG.

04/20/23 6

Seismicity and main tectonic features

Seismological studies are revealing the geological structure and dynamics of the PNG region on both large and smaller scales. The boundaries of the lithospheric plates in the PNG region are becoming clearer, although some boundaries remain uncertain. The nature of the processes at the plate boundaries are also being revealed by seismological studies.

Fault zones in the PNGProgressive study of EQ helps to:

define crustal structure-PNG region gets squeezed by the WSW movement of the Pacific plate interacting with the NNE movement of the Indo-Australian plate. With the help of processed seismic data (such as FMS) different types of seismic faults can be identified.

Divergent faultConvergent faultNormal fault

Direction of plate motion(Johnson, R. W., (2000))

Seismic Zones for PNG RegionSeismic studies help

us Define seismic

zones in PNG Establish PNG

Building Code. Propose changes

in the design and construction of the actual structure.

Seismic zones defining PNG Building code. The numbers represent the level of risk from low (4) to high (1), with the likely threat of corresponding surface wave magnitudes for the zones.

EQ Occurrences PROBABILITEISStudies have been conducted to determine return periods

and probabilities of occurrence of large earthquakes.

The calculation are performed based on

Bed rock site condition

Site condition inferred from Vs30 map for East New Britain region.

Generally, the hazard level is higher in the southeast part of the region. This is mainly due to the geometry & distance to the subduction zone interface.

Economic benefits to the State

Avoidance of property damage and deaths caused by geological hazards through improved safety and quality of life of geohazards-threatened communities

Increases in land values because of better planning for well understood hazards specific for those particular geological environments

Integrated benefits from measures to mitigate geological hazards far outweighs the cost of maintaining geohazards monitoring activities04/20/23 11

ConclusionGIS Seismic data collected can help us ;Identify different types of fault s categorize region into different seismic zonesTo define building codeto promptly provide technical information and

advice to the State, disaster authorities, line agencies and the general public

Help us to identify location that are more stable from effects earthquake shaking for major government infrastructure development

Make appropriate geological hazards policy

04/20/23 13