scholarly journals Source reconstruction of the 1969 Majene, Sulawesi earthquake and tsunami: A preliminary study

2021 ◽  
Vol 873 (1) ◽  
pp. 012054
Author(s):  
I.R. Pranantyo ◽  
A. Cipta ◽  
H.A. Shiddiqi ◽  
M. Heidarzadeh
Keyword(s):  
Maximum Intensity ◽  
Observation Data ◽  
Macroseismic Data ◽  
Tsunami Height ◽  
Earthquake Scenarios ◽  
Scenario Earthquakes ◽  
Damage Data ◽  
Earthquake Model ◽  
First Motion ◽  
Preliminary Study

Abstract We studied the February 23rd, 1969 M7.0 Majene, Sulawesi earthquake and tsunami. It was followed by tsunami reported at five locations. At least 64 people were killed and severe damage on infrastructures were reported in Majene region. Based on damage data, we estimated that the maximum intensity of the earthquake was MMI VIII. Focal mechanisms, derived using first motion polarity analysis, indicated that the earthquake had a thrust mechanism. Furthermore, we built hypothetical earthquake scenarios based on a rectangular fault plane of 40 km × 20 km with a homogeneous slip model of 1.5 m. We run the Open Quake and the JAGURS code to validate the macroseismic and tsunami observation data, respectively. Our best-fitted earthquake model generates maximum intensity of 8+ which is in line with the reported macroseismic data. However, the maximum simulated tsunami height from all scenario earthquakes is 2.25 m which is smaller than the 4 m tsunami height observed at Pelattoang. The possibility of contribution of another mechanism to tsunami generation requires further investigation.

A macroseismic study and the implications of structural damage of two recent major earthquakes in the Jordan Rift

1977 ◽  
Vol 67 (6) ◽  
pp. 1607-1613
Author(s):  
M. Vered ◽  
H. L. Striem
Keyword(s):  
Quantitative Analysis ◽  
Coastal Plain ◽  
Rift Valley ◽  
Structural Damage ◽  
Macroseismic Data ◽  
Upper Crust ◽  
Structural Trend ◽  
Isoseismal Lines ◽  
Damage Data ◽  
Instrumental Records

abstract A detailed macroseismic study of the July 11, 1927 earthquake was carried out. A quantitative analysis of damage data provided a correlation for estimating (MM) intensities: I = 6.4 + 1.2 log (percentage of damaged houses). Using axis lengths and areas bounded by the ensuing isoseismal lines, the depth (16 to 28 km) of the event was estimated, and its probable epicenter located near Damiya bridge on the Jordan river. A comparison with the equivalent parameters, inferred from instrumental records, shows agreement between both sets of results and thus confirms the validity of the approach used in the macroseismic study. The same procedure of studying macroseismic data was applied to an earlier (January 1, 1837) destructive earthquake. It was found that this latter event orginated in the upper crust, eastward of Safed, with a 6.25 to 6.5 magnitude. The isoseismals of both these major earthquakes are elongated in a north-south direction, along the major structural trend in the area. The southern coastal plain of Israel seems generally less vulnerable to Jordan Rift Valley earthquakes than inland regions of similar epicentral distances, though local pockets of anomalous intensities are observed for both earthquakes.

Simulation of Tsunami Inundation in Central Peru from Future Megathrust Earthquake Scenarios

2014 ◽  
Vol 9 (6) ◽  
pp. 961-967 ◽  
Author(s):  
Erick Mas ◽  
◽  
Bruno Adriano ◽  
Nelson Pulido ◽  
Cesar Jimenez ◽  
...  
Keyword(s):  
Hazard Mapping ◽  
Slip Model ◽  
Tsunami Height ◽  
Ground Acceleration ◽  
Tsunami Inundation ◽  
Tsunami Simulation ◽  
Earthquake Scenarios ◽  
Spatially Correlated ◽  
Megathrust Earthquakes ◽  
Interseismic Coupling

We estimated, from twelve scenarios of potential megathrust earthquakes, the tsunami impact on the Lima-Callao region in Central Peru. In addition, we conducted hazard mapping using the local envelope of the maximum inundation simulated in these scenarios. The deterministic approach is supported by the decades of geodetic measurements in this area that characterize the interseismic strain build up since historical megathrust earthquakes. The earthquake scenarios for simulation proposed in [1] introduce spatially correlated short-wavelength slip heterogeneities to a first slip model in [2] calculated from the interseismic coupling (ISC) distribution in Central Peru. The ISC was derived from GPS monitoring data as well as from historical earthquake information. The results of strong ground motion simulations in [1] reported that the slip scenario with the deepest average peak values along the strike (Mw= 8.86) generates the largest PGA in the Lima-Callao area. In this study, we found from tsunami simulation results that the slip model with the largest peak slip at a shallow depth (Mw= 8.87) yielded the highest tsunami inundation. Such differences in maximum scenarios for peak ground acceleration and tsunami height reveal the importance of a comprehensive assessment of earthquake and tsunami hazards in order to provide plausible worstcase scenarios for disaster risk management and education.

scholarly journals FIRST LANGUAGE ACQUISITION ON A THREE-YEAR-OLD CHILD

2021 ◽  
Vol 3 (2) ◽  
pp. 267-279
Author(s):  
Yuliana Friska ◽  
Moh. Thoyib Syafi'i
Keyword(s):  
Language Acquisition ◽  
Morphological Analysis ◽  
First Language ◽  
Deep Understanding ◽  
Qualitative Approach ◽  
Observation Data ◽  
First Language Acquisition ◽  
Preliminary Study ◽  
Natural Result ◽  
Syntactical Analysis

Studying children’s language acquisition is quite fascinating to be conducted because as we know     that the astonishing advancement of their language obtaining from 0 to 3 years or more. The aim of the study is to obtain deep understanding about language acquisition on a three-year old child "Gadis Mardhiyah" and to observe language development of her. Besides, this study uses qualitative approach. In this case, researcher observes her daily conversation in her surrounding in order to get the natural result without any setting. This study was conducted at her house in Bintaro sector 9 Pd. Pucung Tangerang Selatan. Regarding this, the study was conducted for four weeks and preliminary study was done for a month before the researcher doing her observation. Data analysis was carried stage by stage in accordance prior to the focus of the problems. After the data obtained through observation and document inductively processed, then the next step is to define the meaning on the basis of phonological analysis, morphological analysis, syntactical analysis, and discourse analysis. Based on the analysis, it can be concluded that Gadis was able to communicate properly and appropriately according to her age.

scholarly journals Self-similar stochastic slip distributions on a non-planar fault for tsunami scenarios for megathrust earthquakes

2020 ◽  
Author(s):  
Masaru Nakano ◽  
Shane Murphy ◽  
Ryoichiro Agata ◽  
Yasuhiko Igarashi ◽  
Masato Okada ◽  
...  
Keyword(s):  
Arrival Time ◽  
Near Field ◽  
Early Warning Systems ◽  
Disaster Mitigation ◽  
Slip Distribution ◽  
Height Distribution ◽  
Tsunami Height ◽  
Arrival Times ◽  
Megathrust Earthquakes ◽  
Scenario Earthquakes

Abstract Megathrust earthquakes that occur repeatedly along the plate interface of subduction zones can cause severe damage due to strong ground motion and the destructive tsunamis they can generate. We developed a set of scenario earthquakes to evaluate tsunami hazards and tsunami early warning systems for such devastating earthquakes. Although it is known that the slip distribution on a fault strongly affects the tsunami height distribution in near-field coastal areas, the slip distribution of future earthquakes cannot be exactly predicted. One way to resolve this difficulty is to create a set of scenario earthquakes in which a set of heterogeneous slip distributions on the source fault is stochastically generated based on a given slip probability density function (SPDF). The slip distributions generated in this manner differ from event to event, but their average over a large ensemble of models converges to a predefined SPDF resembling the long-term average of ruptures on the target fault zone. We created a set of SPDF-based scenario earthquakes for an expected future M w 8.2 Tonankai earthquake in the eastern half of the Nankai trough, off southwest Japan, and computed the ensuing tsunamis. We found that the estimated peak coastal amplitudes among the ensemble of tsunamis along the near-field coast differed by factors of 3 to 9 and the earliest and latest arrivals at each observation site differed by 400 to 700 s. The variations in both peak tsunami amplitude and arrival time at each site were well approximated by a Gaussian distribution. For cases in which the slip distribution is unknown, the average and standard deviation of these scenario datasets can provide first approximations of forecast tsunami height and arrival time and their uncertainties, respectively. At most coastal observation sites, tsunamis modelled similarly but using a uniform slip distribution underpredicted tsunami amplitudes but gave earlier arrival times than those modeled with a heterogeneous slip distribution. Use of these earlier arrival times may be useful for providing conservative early warnings of tsunami arrivals. Therefore, tsunami computations for both heterogeneous and uniform slip distributions are important for tsunami disaster mitigation.

Modeling Post-Earthquake Functionality of Regional Health Care Facilities

2010 ◽  
Vol 26 (3) ◽  
pp. 869-892 ◽  
Author(s):  
Soheil Yavari ◽  
Stephanie E. Chang ◽  
Kenneth J. Elwood
Keyword(s):  
Los Angeles ◽  
Significant Loss ◽  
Health Care Facilities ◽  
Seismic Safety ◽  
Earthquake Scenario ◽  
Earthquake Scenarios ◽  
Response Planning ◽  
Regional Health Care ◽  
Before And After ◽  
Damage Data

This study introduces a methodology for anticipating the post-earthquake functionality of hospitals in a region. Performance levels for interacting systems (structural, nonstructural, lifeline, and personnel) in a hospital are operationally defined, empirically correlated, and probabilistically modeled using damage data from past earthquakes. Separate models are developed for buildings built before and after the 1973 California Hospital Seismic Safety Act. Performance estimates of the systems are used to anticipate overall hospital functionality. Effects of external power and water outage are also included. As a case study, the methodology is utilized to predict the functionality of hospitals in Los Angeles County for two earthquake scenarios. Findings indicate that in a M6.9 Verdugo fault earthquake scenario, nearly half of county hospitals have at least a 50% chance of experiencing significant loss of functionality. Such findings can support emergency response planning as well as seismic retrofit prioritization.

scholarly journals Self-similar stochastic slip distributions on a non-planar fault for tsunami scenarios for megathrust earthquakes

2020 ◽  
Author(s):  
Masaru Nakano ◽  
Shane Murphy ◽  
Ryoichiro Agata ◽  
Yasuhiko Igarashi ◽  
Masato Okada ◽  
...  
Keyword(s):  
Arrival Time ◽  
Near Field ◽  
Early Warning Systems ◽  
Disaster Mitigation ◽  
Slip Distribution ◽  
Height Distribution ◽  
Tsunami Height ◽  
Arrival Times ◽  
Megathrust Earthquakes ◽  
Scenario Earthquakes

Abstract Megathrust earthquakes that occur repeatedly along the plate interface of subduction zones can cause severe damage due to strong ground motion and the destructive tsunamis they can generate. We developed a set of scenario earthquakes to evaluate tsunami hazards and tsunami early warning systems for such devastating earthquakes. Although it is known that the slip distribution on a fault strongly affects the tsunami height distribution in near-field coastal areas, the slip distribution of future earthquakes cannot be exactly predicted. One way to resolve this difficulty is to create a set of scenario earthquakes in which a set of heterogeneous slip distributions on the source fault is stochastically generated based on a given slip probability density function (SPDF). The slip distributions generated in this manner differ from event to event, but their average over a large ensemble of models converges to a predefined SPDF resembling the long-term average of ruptures on the target fault zone. We created a set of SPDF-based scenario earthquakes for an expected future Mw 8.2 Tonankai earthquake in the eastern half of the Nankai trough, off southwest Japan, and computed the ensuing tsunamis. We found that the estimated peak coastal amplitudes among the ensemble of tsunamis along the near-field coast differed by factors of 3 to 9 and the earliest and latest arrivals at each observation site differed by 400 to 700 s. The variations in both peak tsunami amplitude and arrival time at each site were well approximated by a Gaussian distribution. For cases in which the slip distribution is unknown, the average and standard deviation of these scenario datasets can provide first approximations of forecast tsunami height and arrival time and their uncertainties, respectively. At most coastal observation sites, tsunamis modelled similarly but using a uniform slip distribution underpredicted tsunami amplitudes but gave earlier arrival times than those modeled with a heterogeneous slip distribution. Use of these earlier arrival times may be useful for providing conservative early warnings of tsunami arrivals. Therefore, tsunami computations for both heterogeneous and uniform slip distributions are important for tsunami disaster mitigation.

scholarly journals Attenuating intensities

1996 ◽  
Vol 39 (5) ◽  
Author(s):  
L. Peruzza
Keyword(s):  
Data Sets ◽  
Macroseismic Data ◽  
Source Depth ◽  
Physical Content ◽  
Earthquake Scenarios ◽  
Point Measure ◽  
Definition Of ◽  
Tectonic Style ◽  
Propagation Properties ◽  
Epicentral Intensity

The study presents a methodology in which fractile distances for a given macroseismic intensity are used as a point measure on which to do attenuation characterization. The use of statistically derived distances expected not to be exceeded at a given probability avoids ambiguous definition of isoseismal radii, and consequent mis- interpretation of attenuation parameters with a physical content. The utility and definiteness of such a fractile distance is evident when treating many earthquakes, of different magnitudes and for which the macroseismic data-sets are of different sizes. The methodology is applied to 55 Italian earthquakes of the last four centuries, with epicentral intensity ranging from VII to XI MCS. Propagation properties in volcanic districts are peculiar, with a rapid decay of observed intensity from the epicentre. The attenuation properties of the other crustal en- vironments are not clcarly correlated with the geodynamic domain; the earthquakes show a mean behaviour that appears to depend on relatively homogeneous conditions of propagation. Source depth, tectonic style and finiteness of the source are not addressed because only macroseismic surveying had been applied to most of the earthquakes, and they cannot be linked to surficial fault ruptures. The study is intended to provide mean attenuations that can be used in probabilistic seismic hazard studies; the variabiljty of individual earthquake attenuations for a region introduces the need to use different parameters in future deterministic earthquake scenarios.

Sign in / Sign up

Export Citation Format

Share Document