The probability of coseismic landslides in different peak ground accelerations: a case of 1927 Gulang M8.0 event

On 16 September, 1972 at 04 15 09.8 UT an earthquake of magnitude ML 5.0 occurred in southeast Papua within about 20 km of a proposed dam site on the Musa River. The earthquake triggered two accelerographs, Musa A and Musa B, one at the crest and one at the base of the dam site. The peak ground accelerations recorded by the accelerographs were 1.85 m/s2 and 0.39 m/s2 respectively; the peak ground velocities were 87 mm/s and 2.0 mm/s; and the corresponding mean periods of the ground motion were about 0.23 and 0.04 s. The difference in the nature of the accelerograms is attributed to the difference in the geological and topographical settings of the accelerograph sites. The upper site has an elevation of 406 m and consists of about 60 m of weathered sediments overlying fresh ultramafics. The lower site has an elevation of 112 m and consists of an outcrop of the ultramafic complex.

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Attenuation of peak ground accelerations in some recent New Zealand earthquakes

Bulletin of the New Zealand Society for Earthquake Engineering ◽

10.5459/bnzsee.26.1.3-13 ◽

1993 ◽

Vol 26 (1) ◽

pp. 3-13 ◽

Cited By ~ 6

Author(s):

D. J. Dowrick ◽

S. Sritharan

Keyword(s):

New Zealand ◽

Strong Motion ◽

Medium Size ◽

Data Sets ◽

Fault Rupture ◽

Motion Data ◽

Peak Ground Accelerations ◽

The Mean ◽

Using Data ◽

Event Based

The attenuation of peak ground accelerations was studied for eight New Zealand earthquakes which occurred in the period 1987 to 1991. These events were of medium size with moment magnitudes in the range Mw = 5.8 - 6.7, with depth to centroids of the fault rupture ranging from 4 to 60 km. Attenuation of peak ground accelerations was examined for each event, based on the slope distance from the rupture surface to each strong motion data site. The mean regression attenuation curve for each event was compared with those derived by others using data sets from other parts of the world, allowance being made for source mechanism and depth. Excepting the 1988 Te Anau event, the other seven New Zealand events as a set closely match a Japanese model, but give significantly stronger accelerations than those predicted by the models from western USA and Europe.

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Attenuation of peak ground accelerations in New Zealand earthquakes

Bulletin of the New Zealand Society for Earthquake Engineering ◽

10.5459/bnzsee.30.2.133-158 ◽

1997 ◽

Vol 30 (2) ◽

pp. 133-158 ◽

Cited By ~ 14

Author(s):

J. X. Zhao ◽

D. J. Dowrick ◽

G. H. McVerry

Keyword(s):

New Zealand ◽

Substantial Effect ◽

Tectonic Plates ◽

The Pacific ◽

Source Distance ◽

Shortest Distance ◽

Soil Deposits ◽

Peak Ground Accelerations ◽

The Difference ◽

Rock And Soil

The main result of this study is the development of attenuation expressions for peak ground accelerations (PGAs) in New Zealand earthquakes, in terms of magnitude Mw and shortest distance from the source. Other factors which are modelled are depth, focal mechanism, ground class and tectonic type of earthquake i.e. crustal, interface or dipping slab. As well as being implied in the source distance, the substantial effect of depth is modelled well with a separate linear depth term. For crustal events, focal mechanisms which are predominantly reverse are found to cause PGAs that are 28 percent stronger on average than for other mechanisms. PGAs at soil sites (ie those having soil deposits >3 m thick) are found to be 53 percent stronger on average than at other (ie rock) sites, but the difference between PGAs on rock and soil sites in large amplitude shaking remains uncertain, ie near the source o f events of Mw ≥ 7. Earthquakes occurring on the interface between the Pacific and Australian tectonic plates give rise to smaller PGAs than do crustal or slab events of the same magnitude, depth and distance. Comparisons are made between our New Zealand model and some for Europe, Japan and the Western USA.

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Seismic Performance Evaluation of Fire Stations in Shelby County, Tennessee

Earthquake Spectra ◽

10.1193/1.1585979 ◽

1997 ◽

Vol 13 (4) ◽

pp. 759-772 ◽

Cited By ~ 3

Author(s):

Howard H. M. Hwang ◽

Huijie Lin ◽

Jun-Rong Huo

Keyword(s):

Performance Evaluation ◽

Seismic Performance ◽

Fragility Curves ◽

Seismic Performance Evaluation ◽

Scenario Earthquakes ◽

Peak Ground Accelerations ◽

Shelby County ◽

Fire Stations ◽

Heavy Damage

This paper presents an evaluation of the seismic performance of fire stations in Shelby County, Tennessee. Data relevant to 71 fire stations were collected and implemented as a database using Professional MapInfo. The peak ground accelerations resulting from two scenario earthquakes with moment magnitudes of 6.5 and 7.0 at Marked Tree, Arkansas, were estimated at these fire stations. Furthermore, the fragility curves for various types of buildings in the Memphis area were established based on the fragility data available in the literature. Using these fragility curves, the expected damage to all the fire stations caused by both scenario earthquakes was determined. The results indicate that most of the fire stations will suffer moderate to heavy damage and are expected to be out of operation after the earthquakes. Thus, the authorities need to take appropriate action to mitigate the risks posed by the loss of fire stations.

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Coseismic landslides induced by the 2018 Mw 6.6 Iburi, Japan, Earthquake: spatial distribution, key factors weight, and susceptibility regionalization

Landslides ◽

10.1007/s10346-020-01522-3 ◽

2020 ◽

Author(s):

Ming Chang ◽

Yu Zhou ◽

Chao Zhou ◽

Tristram C. Hales

Keyword(s):

Spatial Distribution ◽

Key Factors ◽

Coseismic Landslides

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Landslides Triggered by the 2016 Mw 7.8 Pedernales, Ecuador Earthquake: Correlations with ESI-07 Intensity, Lithology, Slope and PGA-h

Geosciences ◽

10.3390/geosciences9090371 ◽

2019 ◽

Vol 9 (9) ◽

pp. 371 ◽

Cited By ~ 8

Author(s):

Kervin Chunga ◽

Franz A. Livio ◽

Carlos Martillo ◽

Hernán Lara-Saavedra ◽

Maria Francesca Ferrario ◽

...

Keyword(s):

Environmental Effects ◽

Focal Depth ◽

Lateral Spreading ◽

Primary Data ◽

Ground Acceleration ◽

Epicentral Area ◽

Coseismic Landslides ◽

Subduction Earthquakes ◽

Rupture Plane ◽

Hilly Region

We provide a dataset of the landslides induced by the 2016 Pedernales megathrust earthquake, Ecuador (Mw 7.8, focal depth of 20 km) and compare their spatial distribution with mapped bedrock lithology, horizontal peak ground acceleration (PGA-h) and the macroseismic intensity based on earthquake-induced environmental effects (ESI-07). We studied 192 coseismic landslides (classified as coherent, disrupted and lateral spreads) located in the epicentral area, defined by the VII to IXESI-07 isoseismals. Based on our findings, lahar deposits, tuffs and volcanoclastic units are the most susceptible to landslides occurrence. Alluvial plains with fluvial loose fine sand are the most susceptible setting for lateral spreading, with a maximum intensity of IXESI-07. The coherent landslides are frequently found in altered shale and siltstone geological units with moderate slopes (8°–16°), with typical intensity ranging between VII and VIIIESI-07. Our analysis draws a typical framework for slope movements triggered by subduction earthquakes in Ecuador. The most dangerous setting is the coastal region, a relatively highly urbanized area located near the epicenter and where liquefaction can trigger massive lateral spreading events. Coherent and disrupted landslides, dominating the more internal hilly region, can be triggered also in moderate slope settings (i.e., less than 10°). Indeed, the regression analysis between seismic intensity, PGA-h and landslide occurrence shows that most of the events occurred at PGA-h values between 0.4 g and 1.2 g, at a distance of 30 to 50 km from the rupture plane. Our database suggests that lithology and hillslope geometry are the main geological/geomorphological factors controlling coseismic landslides occurrence; while the distance from the rupture plane plays a significant role on determining the landslide size. Finally, we underline that coseismically-triggered landslides are among the most common environmental effects occurring during large subduction events that can be effectively used to properly evaluate the earthquake macroseismic field. The landslide inventory we compiled is suitable for assessing the vulnerability of physical environment from subduction earthquakes in Ecuador, and offers a primary data source for future worldwide analysis.

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Attenuation Function Relationship for Far Field Earthquake Considered by Strike Slip Mechanism

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.754-755.897 ◽

2015 ◽

Vol 754-755 ◽

pp. 897-901

Author(s):

Saffuan Wan Ahmad ◽

Azlan Adnan ◽

Rozaimi Mohd Noor ◽

Khairunisa Muthusamy ◽

Sk Muiz Sk Razak ◽

...

Keyword(s):

Peak Ground Acceleration ◽

Strike Slip ◽

Far Field ◽

Attenuation Relationship ◽

Ground Acceleration ◽

Slip Mechanism ◽

Earthquake Sources ◽

Peak Ground Accelerations ◽

Function Relationship ◽

The Relationship

An attenuation relationship for far field earthquakes considered by strike slip has been developed. The attenuation relationship function was develop using regression analysis. The database consisting of more than 130 peak ground accelerations from seven earthquake sources recorded by Seismology Station in Malaysia have been used to develop the relationship. This study aims to investigate the new relationship attenuation to gain exact peak ground acceleration at the location on site. Based on this study, the location is a structure located at Terengganu seaside.

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