Probabilistic seismic hazard analysis of New Zealand

The seismic hazard from ground motions during a New Zealand earthquake is variable, and is dependent on the different tectonic processes that occur throughout the country. A modem probabilistic seismic hazard analysis (PSHA) combines various data sets to take account of these different environmental effects and rates of occurrence. Earthquake catalogue data can be used to give the rate of background or distributed seismicity in historical times, while paleoseismic data can be used to constrain the return time of large earthquakes. The background seismicity is assumed to occur as a time-independent Poisson process. To apply this assumption to a new PSHA of New Zealand, completeness levels for the New Zealand earthquake catalogue were established, and aftershocks or clusters of events that occurred close together in both space and time were removed from the catalogue. The level of hazard in a region can be depth-dependent, that is the risk of a large earthquake may come from a shallow crustal event or a deep subduction zone event, both having the same epicentral location but resulting in different levels of damage. The New Zealand earthquake catalogue has too many events that have been assigned restricted depths to be ignored. These events have been statistically redistributed into shallow crustal zones or deep subducted slab zones based on the last eleven years of catalogue data, when improvements in technology have reduced the number of restricted events.

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Consideration and Propagation of Epistemic Uncertainties in New Zealand Probabilistic Seismic-Hazard Analysis

Bulletin of the Seismological Society of America ◽

10.1785/0120110257 ◽

2012 ◽

Vol 102 (4) ◽

pp. 1554-1568 ◽

Cited By ~ 5

Author(s):

B. A. Bradley ◽

M. W. Stirling ◽

G. H. McVerry ◽

M. Gerstenberger

Keyword(s):

New Zealand ◽

Seismic Hazard ◽

Hazard Analysis ◽

Probabilistic Seismic Hazard Analysis ◽

Seismic Hazard Analysis ◽

Probabilistic Seismic Hazard

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PEMETAAN DAERAH RENTAN GEMPA BUMI SEBAGAI DASAR PERENCANAAN TATA RUANG DAN WILAYAH DI PROVINSI SULAWESI BARAT

KURVATEK ◽

10.33579/krvtk.v1i2.417 ◽

2017 ◽

Vol 1 (2) ◽

pp. 41-47

Author(s):

Marinda noor Eva

Keyword(s):

Seismic Hazard ◽

Hazard Analysis ◽

Probabilistic Seismic Hazard Analysis ◽

Seismic Hazard Analysis ◽

Probabilistic Seismic Hazard

Penelitian mengenai daerah rawan gempa bumi ini menggunakan Metode Probabilistic Seismic Hazard Analysis (PSHA) di Provinsi Sulawesi Barat, dengan tujuan untuk memetakan tingkat kerawanan bahaya gempa bumi di Kabupaten Mamasa. Penelitian ini menggunakan data kejadian gempa bumi di Pulau Sulawesi dan sekitarnya dari tahun 1900 – 2015. Hasil pengolahan PSHA menggunakan Software Ez-Frisk 7.52 yang menghasilkan nilai hazard di batuan dasar pada kondisi PGA (T = 0,0 sekon), dengan periode ulang 500 tahun dan 2500 tahun berkisar antara (149,54 – 439,45) gal dan (287,18 – 762,81) gal. Nilai hazard di batuan dasar dengan kondisi spektra T = 0,2 sekon untuk periode ulang 500 tahun dan 2500 tahun adalah (307,04 – 1010,90) gal dan (569,48 – 1849,78) gal. Nilai hazard di batuan dasar dengan kondisi spektra T = 1,0 sekon untuk periode ulang 500 tahun dan 2500 tahun diperoleh nilai (118,01 – 265,75) gal dan (223,74 – 510,92) gal. Berdasarkan analisis PSHA, nilai PGA di Provinsi Sulawesi Barat dominan dipengaruhi oleh sumber gempa sesar.

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