scholarly journals Spatial distributions of earthquake-induced landslides and hillslope preconditioning in the northwest South Island, New Zealand

2015 ◽  
Vol 3 (4) ◽  
pp. 501-525 ◽  
Author(s):  
R. N. Parker ◽  
G. T. Hancox ◽  
D. N. Petley ◽  
C. I. Massey ◽  
A. L. Densmore ◽  
...  
Keyword(s):  
New Zealand ◽  
Regional Scale ◽  
Aftershock Sequence ◽  
Spatial Distributions ◽  
Damage State ◽  
History Of ◽  
Analysis Of Failures ◽  
Seismic Landslide ◽  
Large Earthquakes ◽  
Strong Ground

Abstract. Current models to explain regional-scale landslide events are not able to account for the possible effects of the legacy of previous earthquakes, which have triggered landslides in the past and are known to drive damage accumulation in brittle hillslope materials. This paper tests the hypothesis that spatial distributions of earthquake-induced landslides are determined by both the conditions at the time of the triggering earthquake (time-independent factors) and the legacy of past events (time-dependent factors). To explore this, we under\\-take an analysis of failures triggered by the 1929 Buller and 1968 Inangahua earthquakes, in the northwest South Island of New Zealand. The spatial extents of landslides triggered by these events were in part coincident. Spatial distributions of earthquake-triggered landslides are determined by a combination of earthquake and local characteristics, which influence the dynamic response of hillslopes. To identify the influence of a legacy from past events, we first use logistic regression to control for the effects of time-independent variables. Through this analysis we find that seismic ground motion, hillslope gradient, lithology, and the effects of topographic amplification caused by ridge- and slope-scale topography exhibit a consistent influence on the spatial distribution of landslides in both earthquakes. We then assess whether variability unexplained by these variables may be attributed to the legacy of past events. Our results suggest that hillslopes in regions that experienced strong ground motions in 1929 were more likely to fail in 1968 than would be expected on the basis of time-independent factors alone. This effect is consistent with our hypothesis that unfailed hillslopes in the 1929 earthquake were weakened by damage accumulated during this earthquake and its associated aftershock sequence, which influenced the behaviour of the landscape in the 1968 earthquake. While our results are tentative, they suggest that the damage legacy of large earthquakes may persist in parts of the landscape for much longer than observed sub-decadal periods of post-seismic landslide activity and sediment evacuation. Consequently, a lack of knowledge of the damage state of hillslopes in a landscape potentially represents an important source of uncertainty when assessing landslide susceptibility. Constraining the damage history of hillslopes, through analysis of historical events, therefore provides a potential means of reducing this uncertainty.

scholarly journals Spatial distributions of earthquake-induced landslides and hillslope preconditioning in northwest South Island, New Zealand

2015 ◽  
Vol 3 (1) ◽  
pp. 1-52 ◽  
Author(s):  
R. N. Parker ◽  
G. T. Hancox ◽  
D. N. Petley ◽  
C. I. Massey ◽  
A. L. Densmore ◽  
...  
Keyword(s):  
New Zealand ◽  
Regional Scale ◽  
Aftershock Sequence ◽  
Spatial Distributions ◽  
Damage State ◽  
Local Characteristics ◽  
History Of ◽  
Analysis Of Failures ◽  
Landslide Distribution ◽  
Strong Ground

Abstract. Current models to explain regional-scale landslide events are not able to account for the possible effects of the legacy of previous earthquakes, which have triggered landslides in the past and are known to drive damage accumulation in brittle hillslope materials. This paper tests the hypothesis that spatial distributions of earthquake-induced landslides are determined by both the conditions at the time of the triggering earthquake (time-independent factors), and also the legacy of past events (time-dependent factors). To explore this, we undertake an analysis of failures triggered by the 1929 Buller and 1968 Inangahua earthquakes, in the northwest South Island of New Zealand. The spatial extent of landslides triggered by these events was in part coincident (overlapping). Spatial distributions of earthquake-triggered landslides are determined by a combination of earthquake and local characteristics, which influence the dynamic response of hillslopes. To identify the influence of a legacy from past events, we use logistic regression to control for the effects of time-independent variables (seismic ground motion, hillslope gradient, lithology, and the effects of topographic amplification caused by ridge- and slope-scale topography), in an attempt to reveal unexplained variability in the landslide distribution. We then assess whether this variability can be attributed to the legacy of past events. Our results suggest that the 1929 Buller earthquake influenced the distribution of landslides triggered by the 1968 Inangahua earthquake. Hillslopes in regions that experienced strong ground motions in 1929 were more likely to fail in 1968 than would be expected on the basis of time-independent factors alone. This effect is consistent with our hypothesis that unfailed hillslopes in the 1929 earthquake were weakened by damage accumulated during this earthquake and its associated aftershock sequence, and this weakening then influenced the performance of the landscape in the 1968 earthquake. While our results are tentative, the findings emphasize that a lack of knowledge of the damage state of hillslopes in a landscape potentially represents an important source of uncertainty when assessing landslide susceptibility. Constraining the damage history of hillslope materials, through analysis of historical events, therefore provides a potential means of reducing this uncertainty.

New Japanese Guidelines for the Information of the Prospect of Seismic Activity After Large Earthquakes and Their Applications

2017 ◽  
Vol 12 (6) ◽  
pp. 1109-1116
Author(s):  
Noriko Kamaya ◽  
Kiyoshi Takeda ◽  
Tetsuo Hashimoto ◽  
◽  
Keyword(s):  
Seismic Activity ◽  
Seismic Intensity ◽  
Aftershock Sequence ◽  
Lessons Learned ◽  
Japan Meteorological Agency ◽  
Aftershock Activity ◽  
Research Committee ◽  
New Guidelines ◽  
Large Earthquakes ◽  
Strong Ground

The Kumamoto Prefecture suffered an earthquake of MJMA6.5 on April 14, 2016 at 21:26 (Japan Standard Time). A seismic intensity of 7, on the Japan Meteorological Agency (JMA) seismic intensity scale, was observed, which, by definition, is the maximum possible value. After 18 hours of the earthquake, the JMA issued a prospect for aftershock activity, where the probability of aftershocks with a seismic intensity of 6 Lower (6-) or greater, was 20% within three days following 16:00 JST on April 15, 2016. Ten hours post the issuance of the prospect, at 01:25 on April 16, a larger earthquake of MJMA7.3, with a maximum JMA seismic intensity of 7, occurred in the same region as the MJMA6.5 event, triggering many distant earthquakes. As this seismic occurrence did not follow a mainshock-aftershock sequence, the JMA discontinued the issuance of prospective aftershock activity. With lessons learned from this occurrence sequence, the Earthquake Research Committee of Japan (ERC), including JMA, seismologists and social scientists, have formulated new guidelines for the assessment of successive seismic activity, in order to enhance the understanding of strong ground motions after large earthquakes. The five main points of the guidelines are as follows: (1) alert to a similar strong ground motion, (2) highlighting previous examples of successive large events, (3) consideration of all active source faults, (4) quantitative forecasting of aftershocks a week after the event, and (5) not using the term “aftershock” in information issued by the JMA for disaster prevention. The JMA has commenced the implementation of these new guidelines, effective August 2016.

The U.S. Geological Survey’s Rapid Seismic Array Deployment for the 2019 Ridgecrest Earthquake Sequence

2020 ◽  
Vol 91 (4) ◽  
pp. 1952-1960 ◽  
Author(s):  
Elizabeth S. Cochran ◽  
Emily Wolin ◽  
Daniel E. McNamara ◽  
Alan Yong ◽  
David Wilson ◽  
...  
Keyword(s):  
Fault Zone ◽  
Near Field ◽  
Aftershock Sequence ◽  
Rupture Directivity ◽  
Field Recordings ◽  
Stress Drops ◽  
The City ◽  
Large Earthquakes ◽  
The U.S ◽  
Strong Ground

Abstract Rapid seismic deployments following large earthquakes capture ephemeral near-field recordings of aftershocks and ambient noise that can provide valuable data for seismological studies. The U.S. Geological Survey installed 19 temporary seismic stations following the 4 July 2019 Mw 6.4 and 6 July 2019 (UTC) Mw 7.1 earthquakes near the city of Ridgecrest, California. The stations record the aftershock sequence beginning two days after the mainshock and are expected to remain in the field through approximately January 2020. The deployment augments the permanent seismic network in the area to improve azimuthal coverage and provide additional near-field observations. This article summarizes the motivation and goals of the deployment; details of station installation, instrumentation, and configurations; and initial data quality and observations from the network. We expect these data to be useful for a range of studies including detailing near-field variability in strong ground motions, determining stress drops and rupture directivity of small events, imaging the fault zone, documenting the evolution of crustal properties within and outside of the fault zone, and others.

Challenges facing the farmers of Central Otago

2014 ◽  
Vol 76 ◽  
pp. 25-28
Author(s):  
D.R. Stevens ◽  
J.P. Garden
Keyword(s):  
New Zealand ◽  
Valley Floor ◽  
History Of ◽  
Iconic Status

The Central Otago region, with its cold winters and hot summers, and valley floors with uplift mountains is definitely "a world of difference". At the NZGA conference in Alexandra in 1966 John Hercus stated "Central Otago has a lure which sets it apart from the rest of New Zealand. Its characteristics of geology, topography and climate, its history of occupation and exploitation, its scenery at once forbidding and yet strangely fascinating - these features combine to cast a spell which few who have been exposed, can ever fully escape" (Hercus 1966). The region and its high country have an iconic status epitomised by the "Southern Man" stereotype. This places Central Otago deep in the psyche of the nation. With this goes a unique and significant set of conditions under which farming must take place. Not only does the region have the biophysical challenges of soils, water and climate to contend with, but a wider set of values, often imposed from elsewhere. Fifty years after that first conference we remain challenged. What are the opportunities in front of us and how should we best accommodate the challenge of maintaining a viable enterprise and at the same time, respecting the intense public and customer interest in our use of land and livestock? Central Otago and the associated high country of the Lakes district and McKenzie basin can be divided into three farming types. These are the valley floor irrigable type, the flat and downland dryland regions, and the high country. Each of these has challenges that are at times unique, but often overlap with problems faced in other regions.

The status of Gideon Mantell's “first” Iguanodon tooth in the Museum of New Zealand Te Papa Tongarewa

1997 ◽  
Vol 24 (3) ◽  
pp. 397-421 ◽  
Author(s):  
JOHN C. YALDWYN ◽  
GARRY J. TEE ◽  
ALAN P. MASON
Keyword(s):  
New Zealand ◽  
Charles Lyell ◽  
The Status ◽  
History Of ◽  
Gideon Mantell

A worn Iguanodon tooth from Cuckfield, Sussex, illustrated by Mantell in 1827, 1839, 1848 and 1851, was labelled by Mantell as the first tooth sent to Baron Cuvier in 1823 and acknowledged as such by Sir Charles Lyell. The labelled tooth was taken to New Zealand by Gideon's son Walter in 1859. It was deposited in a forerunner of the Museum of New Zealand, Wellington in 1865 and is still in the Museum, mounted on a card bearing annotations by both Gideon Mantell and Lyell. The history of the Gideon and Walter Mantell collection in the Museum of New Zealand is outlined, and the Iguanodon tooth and its labels are described and illustrated. This is the very tooth which Baron Cuvier first identified as a rhinoceros incisor on the evening of 28 June 1823.

LET'S GO TO FRENZY A Brief History of New Zealand Music TV and Music Video

Perfect Beat ◽  
2015 ◽  
Vol 1 (4) ◽  
pp. 111-121
Author(s):  
Bruce Sheridan ◽  
Philip Hayward
Keyword(s):  
New Zealand ◽  
Music Video ◽  
History Of

Multicultural and Transnational Novels

2018 ◽  
Author(s):  
James Meffan
Keyword(s):  
National Identity ◽  
New Zealand ◽  
The Other ◽  
Colonial History ◽  
History Of ◽  
Return Home ◽  
Access Rights ◽  
The One

This chapter discusses the history of multicultural and transnational novels in New Zealand. A novel set in New Zealand will have to deal with questions about cultural access rights on the one hand and cultural coverage on the other. The term ‘transnational novel’ gains its relevance from questions about cultural and national identity, questions that have particularly exercised nations formed from colonial history. The chapter considers novels that demonstrate and respond to perceived deficiencies in wider discourses of cultural and national identity by way of comparison between New Zealand and somewhere else. These include Amelia Batistich's Another Mountain, Another Song (1981), Albert Wendt's Sons for the Return Home (1973) and Black Rainbow (1992), James McNeish's Penelope's Island (1990), Stephanie Johnson's The Heart's Wild Surf (2003), and Lloyd Jones's Mister Pip (2006).

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