Evaluation of Earthquake-Induced Liquefaction Susceptibility in the Earthquake Prone Areas of Morobe Province, Papua New Guinea

Abstract

Earthquake-induced liquefaction is common in the areas where incidence of earthquake is high along with an amenable soil substratum. However, the extent of liquefaction is controlled by types of site and sub-surface soil-geological factors present in that particular earthquake-prone areas. The earthquake-induced liquefaction can be a major calamity that warrants appropriate investigations in infrastructure development planning. To identify susceptible areas of liquefaction in the earthquake-prone areas, the site soil-geology and earthquake data are mostly needed. There are different approaches used discipline-wise across the world to identify areas that are prone to liquefaction. The output results are used as tools for site selection and also for determining viability of funding in infrastructure development. Liquefaction is one of the main Geo-hazards related to tremor. The presence of saturated soils or unconsolidated sediments in a particular area can pose greater chance of liquefaction at certain earthquake magnitude levels. The study sought to evaluate and assess site and sub-surface soil-geology including historical data on magnitude and frequency of earthquake events that occurred within the study region to identify and demarcate areas that are more susceptible to liquefaction. The main method applied was multi-criteria evaluation using GIS and Remote sensing technologies. Several thematic layers were prepared from the database as mentioned, followed by assigning weightage to each thematic layer generated. The final outputs of liquefaction-prone areas were identified using the weighted overlay tool in ArcGIS 10.2 computer software and were reclassified to show levels of susceptibility from ‘very high', 'high', 'medium', ‘low' to ‘very low’

.