A Bayesian method for estimating earthquake magnitude distribution and changes in the distribution with time and space in New Zealand

abstract Clearly recorded strain steps from three New Zealand earth strain stations for two earthquakes are interpreted by means of Press' strain-field maps. The agreement between calculated and observed steps is excellent when some of the fault parameters are deduced from the earthquake magnitude and used to restrict the possible solutions.

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Aftershock sequence parameters in New Zealand

Bulletin of the Seismological Society of America ◽

10.1785/bssa0880041095 ◽

1998 ◽

Vol 88 (4) ◽

pp. 1095-1097

Author(s):

Donna Eberhart-Phillips

Keyword(s):

New Zealand ◽

Aftershock Sequence ◽

Magnitude Distribution ◽

Generic Models ◽

Earthquake Sequences ◽

Sequence Parameters ◽

Aftershock Hazard

Abstract Regional generic models describing the temporal and magnitude distribution of aftershocks are routinely used in California to assess aftershock hazard. This note applies the Reasenberg and Jones (1989) formulation of aftershock parameters to 17 New Zealand earthquake sequences of M ≧ 5.5, from 1987 through 1995. The median values of the aftershock parameters are similar to those obtained for California.

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TIME, SPACE AND MAGNITUDE CORRELATIONS IN EARTHQUAKE OCCURRENCE

International Journal of Modern Physics B ◽

10.1142/s0217979209063870 ◽

2009 ◽

Vol 23 (28n29) ◽

pp. 5583-5596 ◽

Cited By ~ 5

Author(s):

E. LIPPIELLO ◽

L. DE ARCANGELIS ◽

C. GODANO

Keyword(s):

Earthquake Magnitude ◽

Time Dependent ◽

Scaling Relation ◽

Earthquake Occurrence ◽

Time And Space ◽

Dynamical Scaling ◽

Time Space ◽

Temporal And Spatial ◽

Magnitude Difference ◽

Space Distance

Clustering in time and space is a widely accepted feature of seismicity. Much more questionable is the existence of magnitude correlations. The standard approach to time-dependent seismic hazard generally assumes that magnitudes are independent and therefore, in principle, the next earthquake magnitude is unpredictable. We will show that an earthquake magnitude depends on previous ones: earthquakes occur with higher probability close, not only in time and space, but also in magnitude to previous events. Moreover, the magnitude difference fixes the characteristic temporal and spatial scale controlling correlations between events. As a consequence, the next earthquake tends to have a magnitude similar but smaller than the previous one. We will discuss a dynamical scaling relation between energy, time and space distance that reproduces the main statistical properties of experimental catalogs.

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WATER HARVESTING ON A YELLOW-GREY EARTH

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1977.39.1482 ◽

1977 ◽

pp. 156-160

Author(s):

D.G. Bowler ◽

M.A. Turner

Keyword(s):

New Zealand ◽

Rainfall Intensity ◽

Water Harvesting ◽

Time And Space ◽

Unequal Distribution ◽

The One

THE unequal distribution of rainfall in both time and space is a characteristic of the New Zealand climate. Two farming seasons rarely have the same amount of rain and notable differences can occur between closely located areas. Rainfall intensity and incidence vary greatly from one place to another so that, of all the elements significantly distinguishing climate, it is the one least amenable to generalization.

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Magnitude distribution complexity and variation at The Geysers geothermal field

Geophysical Journal International ◽

10.1093/gji/ggaa208 ◽

2020 ◽

Vol 222 (2) ◽

pp. 893-906

Author(s):

Konstantinos Leptokaropoulos

Keyword(s):

Seismic Hazard ◽

Size Distribution ◽

Hazard Assessment ◽

Seismic Hazard Assessment ◽

B Value ◽

Geothermal Field ◽

Earthquake Magnitude ◽

Fluid Injection ◽

Magnitude Distribution ◽

The Geysers

SUMMARY Earthquake magnitude (size) distribution is a major component required for seismic hazard assessment and therefore, the accurate determination of its functional shape and variation is a task of utmost importance. Although often considered as stationary, the magnitude distribution at particular sites may significantly vary over time and space. In this study, the well-known Gutenberg–Richter (GR) law, which is widely assumed to describe earthquake magnitude distribution, is tested for a case study of seismicity induced by fluid injection at The Geysers (CA, USA) geothermal field. Statistical tests are developed and applied in order to characterize the magnitude distribution of a high quality catalogue comprising seismicity directly associated with two injection wells, at the north western part of The Geysers. The events size distribution variation is investigated with respect to spatial, temporal, fluid injection and magnitude cut-off criteria. A thorough spatio-temporal analysis is performed for defining seismicity Clusters demonstrating characteristic magnitude distributions which significantly differ from the ones of the nearby Clusters. The magnitude distributions of the entire seismic population as well as of the individual Clusters are tested for their complexity in terms of exponentiality, multimodal and multibump structure. Then, the Clusters identified are further processed and their characteristics are determined in connection to injection rate fluctuations. The results of the analysis clearly indicate that the entire magnitude distribution is definitely complex and non-exponential, whereas subsequent periods demonstrating significantly diverse magnitude distributions are identified. The regional seismicity population is divided into three major families, for one of which exponentiality of magnitude distribution is clearly rejected, whereas for the other two the GR law b-value is directly proportional to fluid injection. In addition, the b-values of these Families seem to be significantly magnitude dependent, a fact that is of major importance for seismic hazard assessment implementations. To conclude, it is strongly suggested that magnitude exponentiality must be tested before proceeding to any b-value calculations, particularly in anthropogenic seismicity cases where complex and time changeable processes take place.

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Temporal variations of the earthquake data in the catalogue of seismicity of New Zealand

Bulletin of the New Zealand Society for Earthquake Engineering ◽

10.5459/bnzsee.38.2.87-105 ◽

2005 ◽

Vol 38 (2) ◽

pp. 87-105 ◽

Cited By ~ 2

Author(s):

F. R. Zuniga ◽

M. Reyners ◽

P. Villamor

Keyword(s):

New Zealand ◽

Temporal Variations ◽

Current Data ◽

Systematic Evaluation ◽

Depth Range ◽

Magnitude Of Completeness ◽

Magnitude Distribution ◽

Seismicity Rates ◽

Frequency Magnitude ◽

Earthquake Data

The authors have analyzed the main temporal characteristics of the earthquake data in the catalogue of seismicity of New Zealand with the objective of providing a general overview of its content and limitations. To this end we have employed different statistical tools which allow for the objective estimate of times of changes in the seismicity rates as well as providing the main reasons for those changes. We have found that the seismicity record of the largest events (M > 4.0) is bracketed by significant changes which occurred during 1940, 1965-1968, and 1987 with other less significant changes taking place during 1960, 1983 and 1992. By comparing the rates obtained for intervals bounded by the aforementioned dates we were able to determine that a linear correction to the magnitudes in the period 1968 to 1987 for the whole depth range of events may be useful in order to match the frequency-magnitude distribution which is obtained using the current data in the interval 1987 - 2004. A different pattern emerged when separating shallow from intermediate and deep events and we found that most of the temporal variations observed affected mainly the deep events (Z > 40 km), and that the reported rate of shallow seismicity for M > 4.0 has been remarkably homogeneous since 1940. This observation is supported not only by the constancy of seismicity rates but by the similarity of frequency-magnitude distributions during the time intervals analyzed. A systematic evaluation of minimum magnitude of completeness for shallow seismicity yielded values of Mc = 4.4 for the interval 1940 to 1968, Mc = 3.9 for the interval 1968 to 1987 and Mc = 2.6 for the current stage from 1987 to 2004. A simple magnitude shift of 0.2 units applied to data in the interval 1968 to 1987 for intermediate and deep events was found to provide a good match to the observed rate for events from 1987 to 2004. The evaluation of Mc for events in the 40 ≤ z ≤ 600 km range yielded values of 5.5 for data in the interval 1940 to 1968, 4.0 for 1968 to 1987, and 3.6 for the current operative practice starting in I 987. A detailed investigation of the variation of the magnitude of completeness with time was carried out resulting in different trends which seem to correspond to the time when major changes were carried out in the network, in particular with the installation and removal of local microcarthquake networks.

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Dancing from Te Kore into Te Ao Marama

Te Kaharoa ◽

10.24135/tekaharoa.v9i1.9 ◽

2016 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Cathy Livermore

Keyword(s):

New Zealand ◽

Indigenous Peoples ◽

Current Practice ◽

Time And Space ◽

Cultural Exchanges ◽

The Future ◽

The Creation ◽

The Universe

Contemporary Indigenous performance awakens and brings into ‘now’ the inherited mauri of all that we are, carried through the wairua from our ancestors and the whenua in the woven whariki of memory held in time and space. Whether in Aotearoa or on another’s whenua, on a stage, in someone’s lounge room or in the ngahere gathering rongoa, when we dance from te kore into te ao marama, we activate ihi, wehi and wana: a power that awakens within and between us and the universe. We come alive in the performance of our cultures and ourselves, see our living relevance today, and are uplifted by our potential to contribute to our world socially, culturally, politically, spiritually and personally. Māori culture activates in me keys and the tools, ways of moving and giving voice, the power to share who I am in my fullness today with other cultures. This presentation reflects on the power of my own current practice as it represents the culmination of my performances, dance teaching, cultural exchanges and facilitation experiences within New Zealand and internationally. How might performing as Maori and Indigenous peoples be seen to strengthen and empower our selves, communities and cultures, whoever and wherever we are in the creation of the future?

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Last Words (For Now)

Professional Wrestling ◽

10.14325/mississippi/9781496826862.003.0008 ◽

2020 ◽

pp. 157-158

Author(s):

Sharon Mazer

Keyword(s):

New York ◽

New York City ◽

New Zealand ◽

York City ◽

Performing Arts ◽

Time And Space ◽

Aotearoa New Zealand ◽

Arts Festival ◽

And Performance ◽

Madison Square Garden

The move to Aotearoa New Zealand was transformative in ways I could not have imagined when I left New York City “temporarily” in 1994. From the cheap seats at Madison Square Garden to the VIP tent at Te Matatini National Māori Performing Arts Festival, I continue to embrace the excitement (and terror) of entering into theatre and performance arenas that are emphatically not mine, and to be touched, always, by the generosity of performers and audiences no matter where I find myself. It is tempting to picture Johnny, Larry, and the others frozen in time and space, still at Gleason’s right where I left them. And indeed, Johnny is still there, still teaching youngsters the game and maintaining his claim to fame. He has a website: the ...

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Americans Abroad: Melville and Pacific Perspectives

New Global Studies ◽

10.1515/ngs-2015-0032 ◽

2015 ◽

Vol 9 (3) ◽

Cited By ~ 1

Author(s):

Melissa Gniadek

Keyword(s):

New Zealand ◽

Time And Space ◽

National Space ◽

Personal Experiences ◽

Academic Time ◽

Transnational Study

AbstractThis article draws on experiences of international academic reorientation, specifically time spent in New Zealand, to reflect on the possibilities of bringing the personal and the theoretical together in relation to transnational study. It asks how experiences outside of U.S. national space inflect U.S-based transnational study and whether we can, and should, make academic time and space to acknowledge how personal experiences in particular locations shape what we notice and the questions that we ask in our critical work. More specifically, the essay relates experiences reading and re-reading Herman Melville’s 1855 novella

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