The world's second-largest, recorded landslide event: Lessons learnt from the landslides triggered during and after the 2018 Mw 7.5 Papua New Guinea earthquake

Widespread landslide events provide rare but valuable opportunities to investigate the spatial and size distributions of landslides in relation to seismic, climatic, geological and morphological factors. This study presents a unique event inventory for the co-seismic landslides induced by the February 25, 2018 Mw 7.5 Papua New Guinea earthquake as well as its post-seismic counterparts including the landslides triggered by either aftershocks or succeeding rainfall events that occurred between February 26 and March 19. We mapped approximately 11,500 landslides of which more than 10,000 were triggered by the mainshock with a total failed planimetric area of about 145 km2. Such a large area makes this inventory the world’s second-largest recorded landslide event after the 2008 Wenchuan earthquake. Large landslides are abundant throughout the study area located within the remote Papua New Guinea Highlands. Specifically, more than half of the landslide population is larger than 50,000 m2 and overall, post-seismic landslides are even larger than their co-seismic counterparts. Our analyses indicate that large and widespread landslides were triggered as a result of the compound effects of the strong seismicity, complex geology, steep topography and high rainfall. We statistically show that the 15-day antecedent precipitation, as a predisposing factor, contributes to the spatial distribution of co-seismic landslides. Also, we statistically demonstrate that the cumulative effect of aftershocks is the main factor disturbing steep hillslopes and causing the initiation of very large landslides up to the size of ~5 km2. Taking aside the role of the intense seismic swarm and antecedent precipitation, these inventories also provide evidence for landslide events where the active tectonics contribute to weaken hillslopes and the fatigue damage. Overall, the dataset and the findings provided by this paper is a step forward in seismic landslide hazard assessment of the entire Papua New Guinea mainland.

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The Leapfrog Effect

Managing Globally with Information Technology ◽

10.4018/978-1-93177-742-1.ch010 ◽

2003 ◽

pp. 127-139 ◽

Cited By ~ 4

Author(s):

Stewart T. Fleming

Keyword(s):

Developing Countries ◽

Special Needs ◽

Papua New Guinea ◽

Developing World ◽

New Guinea ◽

Developing Nations ◽

Left Behind ◽

Lessons Learnt ◽

Information And Communication ◽

Made In

Developing countries have special needs for information and communication. In the rush towards globalization of economies and communications, there is a danger that developing nations will get left behind. If we are to close the gap between the “information rich” and “information poor,” then we must take these specific needs into account. This chapter gives an account of some development problems and current initiatives and describes ways in which advancing technology can be manipulated by the developing world to gain social advantage. The term “leapfrog effect” is introduced to explain how advancement can be made in a revolutionary fashion, not incrementally. The chapter draws on the author’s direct experiences in Papua New Guinea, but many of the examples given and lessons learnt are applicable to many other developing nations.

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Mortality surveillance and verbal autopsy strategies: experiences, challenges and lessons learnt in Papua New Guinea

BMJ Global Health ◽

10.1136/bmjgh-2020-003747 ◽

2020 ◽

Vol 5 (12) ◽

pp. e003747

Author(s):

John D Hart ◽

Viola Kwa ◽

Paison Dakulala ◽

Paulus Ripa ◽

Dale Frank ◽

...

Keyword(s):

Mobile Phone ◽

Papua New Guinea ◽

Verbal Autopsy ◽

Health Workers ◽

New Guinea ◽

Local Context ◽

Lessons Learnt ◽

Essential Components ◽

Death Notification ◽

Mortality Surveillance

Full notification of deaths and compilation of good quality cause of death data are core, sequential and essential components of a functional civil registration and vital statistics (CRVS) system. In collaboration with the Government of Papua New Guinea (PNG), trial mortality surveillance activities were established at sites in Alotau District in Milne Bay Province, Tambul-Nebilyer District in Western Highlands Province and Talasea District in West New Britain Province.Provincial Health Authorities trialled strategies to improve completeness of death notification and implement an automated verbal autopsy methodology, including use of different notification agents and paper or mobile phone methods. Completeness of death notification improved from virtually 0% to 20% in Talasea, 25% and 75% using mobile phone and paper notification strategies, respectively, in Alotau, and 69% in Tambul-Nebilyer. We discuss the challenges and lessons learnt with implementing these activities in PNG, including logistical considerations and incentives.Our experience indicates that strategies to maximise completeness of notification should be tailored to the local context, which in PNG includes significant geographical, cultural and political diversity. We report that health workers have great potential to improve the CRVS programme in PNG through managing the collection of notification and verbal autopsy data. In light of our findings, and in consultation with the main government CRVS stakeholders and the National CRVS Committee, we make recommendations regarding the requirements at each level of the health system to optimise mortality surveillance in order to generate the essential health intelligence required for policy and planning.

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Detectability of seismic waves from the submarine landslide that caused the 1998 Papua New Guinea tsunami

10.5194/nhess-2018-317 ◽

2018 ◽

Author(s):

Akio Katsumata ◽

Yasuhiro Yoshida ◽

Kenji Nakata ◽

Kenichi Fujita ◽

Masayuki Tanaka ◽

...

Keyword(s):

Papua New Guinea ◽

Seismic Waves ◽

New Guinea ◽

Submarine Landslide ◽

Coda Waves ◽

Tsunami Source ◽

Direct Result ◽

Northern Coast ◽

Bathymetric Data ◽

Landslide Event

Abstract. On 17 July 1998, a tsunami caused serious damage on the northern coast of Papua New Guinea about 20 min after the mainshock of an Mw 7.0 earthquake. The tsunami has been attributed to a submarine landslide that occurred about 13 min after the mainshock because its arrival at the coast was too late and its height too great to be the direct result of the fault slip of the earthquake. Bathymetric data recorded after the tsunami revealed an amphitheater-like structure that was consistent with a recent submarine landslide. Most current tsunami warning systems are based on analysis of the early arrivals of seismic waves generated by an earthquake. In this study we investigated whether evidence of the landslide could be identified in the coda waves recorded after the mainshock. Based on previous studies of the tsunami source, we constructed synthetic seismograms to represent the submarine landslide and compared them to the observed coda waves of the preceding earthquake, with particular attention to the period around 13 min after the mainshock. We found phases possibly corresponding to the landslide event. However, they were easily covered with coda waves from the mainshock. We concluded that the 1998 landslide was too small to be evident in the coda waves following the magnitude 7 earthquake.

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