Dynamic properties of the Quaternary sedimentary rocks and their influence on seismic site effects. Case study in Bucharest City, Romania

Assessing seismic site effects is essential in earthquake hazard studies. Local seismic amplification is strongly related to the site stratigraphy and topography, the dynamic properties of the subsoil deposits, and the earthquake features. The evaluation of these factors is mandatory to achieve a consistent model of the seismic hazard at small scale. Here we discuss the case of Castelnuovo village (L&#8217;Aquila, central Italy). Located on a small ridge, approximately 60 m higher than the valley floor, the village was heavily struck by April 6, 2009, Mw 6.3 L&#8217;Aquila earthquake, with catastrophic collapse of several buildings. Previous studies ascribed the observed damage to the presence of shallow caves beneath the buildings or to the topographic amplification.In this work, an updated and detailed subsoil model for Castelnuovo site has been provided, based updated geological surveys, such as borehole logs and geophysical data consisting in microtremor measurements and down-hole.These measurements identified resonant frequencies occurring in the range of 0.7-3.0 Hz. These frequency peaks are related to the presence of a velocity contrast at depth between the San Nicandro silts and the Madonna della Neve breccias, as indicated by the performed deep boreholes. Thanks to analytical, numerical, and geostatistical techniques, we identified the main impedance contrast at approximately 210 m depth from the top of the hill, much deeper than previous studies. These new findings allowed to create an accurate and consistent subsoil model summarized by two geological cross-sections of the Castelnuovo ridge, showing that the seismic site effects at the Castelnuovo village are mainly related to stratigraphic amplification.

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Revealing the geological materials properties by a shallow seismic method for investigating slope site effects: a case study of Qiaozhuang town, Qingchuan County, China

Arabian Journal of Geosciences ◽

10.1007/s12517-020-06379-3 ◽

2021 ◽

Vol 14 (2) ◽

Author(s):

Yonghong Luo ◽

Wan Lei ◽

Yunsheng Wang ◽

Xingmao Zhu ◽

Jianfeng Ou

Keyword(s):

Site Effects ◽

Materials Properties ◽

Geological Materials ◽

Seismic Method ◽

Shallow Seismic

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Evaluation of the energy consumption of container diesel trucks in a container terminal: A case study at Klaipeda port

Science Progress ◽

10.1177/00368504211035596 ◽

2021 ◽

Vol 104 (3) ◽

pp. 003685042110355

Author(s):

Tomas Eglynas ◽

Sergej Jakovlev ◽

Valdas Jankunas ◽

Rimantas Didziokas ◽

Jolanta Januteniene ◽

...

Keyword(s):

Energy Consumption ◽

Dynamic Properties ◽

Container Terminal ◽

Superposition Principle ◽

Critical Parameters ◽

Container Transportation ◽

Industrial Emissions ◽

Transportation Process ◽

Diesel Trucks

Introduction: In the paper, we examine the energy consumption efficiency of specialized container diesel trucks engaged in container transportation at a seaport terminal. Objectives: Using the container terminal at Klaipėda in Lithuania as the background for the research, we produced an improved energy consumption model for measuring the theoretical energy consumption and regeneration of diesel trucks at the terminal and provide a comparative analysis. Methods: We created a mathematical model which describes the instantaneous energy consumption of the diesel trucks, taking into account their dynamic properties and the overall geometry of their routes—“Ship-Truck-Stack-Ship”—using the superposition principle. We investigated other critical parameters relevant to the model and provide a statistical evaluation of the transportation process using data from a case study of Klaipėda port, where we collected measurements of container transportation parameters using georeferenced movement detection and logs from wireless equipment positioned on the diesel-powered container trucks. Results: The modeling results showed that an instantaneous evaluation of energy consumption can reveal areas in the container transportation process which have the highest energy loss and require the introduction of new management and process control initiatives to address the regulations which are designed to decrease harmful industrial emissions and encourage novel technologies and thereby increase the eco-friendliness of existing systems. Conclusion: Based on the research results, the article can provide a reference for the estimation of diesel truck efficiency in seaport terminal operations.

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Metamorphism of sedimentary rocks recognised by 19th century French naturalists: A case study from the Chavanon sequence marbles, Massif Central, France

Proceedings of the Geologists Association ◽

10.1016/j.pgeola.2021.05.003 ◽

2021 ◽

Author(s):

Vincent Thiéry

Keyword(s):

19Th Century ◽

Sedimentary Rocks ◽

Massif Central

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Probabilistic Analysis by Applying Uncertainty Worflows: A Case Study of the Teak Field, East Coast Trinidad

10.2118/spe-169924-ms ◽

2014 ◽

Author(s):

C.J.. J. Segnini ◽

M.. Rashwan ◽

M.J.. J. Hernandez ◽

J. A. Rojas ◽

M.A.. A. Infante

Keyword(s):

Reservoir Simulation ◽

Probabilistic Analysis ◽

East Coast ◽

Dynamic Properties ◽

Large Population ◽

Model Performance ◽

Current Standard ◽

Modeling Software ◽

Uncertainty Analyses

Abstract This paper presents a methodology for the probabilistic analysis of an infill or step-out opportunity using numerical simulation. Sensitivity and uncertainty analyses for all involved parameters were evaluated through different experimental design techniques. Subsequently, a proxy model was established to reproduce the numerical model performance. Finally, three appropriate solutions were selected from a large population of realizations corresponding to probabilistic percentiles (90%, 50%, and 10% certainty that the specified volume will be recovered). This proposed methodology helped the asset team to evaluate the well candidates more precisely, confidently, and in less time than the current standard methodology. More knowledge about the variables and their effects on overall outcomes was also gained, which helped the team make more-informed decisions. The workflow used the same numerical modeling software, incorporating and facilitating the changes of both static and dynamic properties simultaneously. A case study from Teak field, on the east coast of Trinidad, illustrates the applicability of the methodology and compares its results to those obtained using the standard workflow for the asset. The methodology is one of the latest developments in reservoir simulation, and it has not yet been incorporated into the operator's common practices and procedures for exploitation of the TSP fields.

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Geospatial Assessment of the Post-Earthquake Hazard of the 2017 Pohang Earthquake Considering Seismic Site Effects

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi7090375 ◽

2018 ◽

Vol 7 (9) ◽

pp. 375 ◽

Cited By ~ 10

Author(s):

Han-Saem Kim ◽

Chang-Guk Sun ◽

Hyung-Ik Cho

Keyword(s):

Site Effects ◽

Focal Depth ◽

Earthquake Hazard ◽

Earthquake Damage ◽

Site Classification ◽

Topographical Effects ◽

Seismic Site Effects ◽

Moderate Earthquake ◽

Seismic Amplification ◽

Earthquake Moment

The 2017 Pohang earthquake (moment magnitude scale: 5.4) was South Korea’s second strongest earthquake in decades, and caused the maximum amount of damage in terms of infrastructure and human injuries. As the epicenters were located in regions with Quaternary sediments, which involve distributions of thick fill and alluvial geo-layers, the induced damages were more severe owing to seismic amplification and liquefaction. Thus, to identify the influence of site-specific seismic effects, a post-earthquake survey framework for rapid earthquake damage estimation, correlated with seismic site effects, was proposed and applied in the region of the Pohang earthquake epicenter. Seismic zones were determined on the basis of ground motion by classifying sites using the multivariate site classification system. Low-rise structures with slight and moderate earthquake damage were noted to be concentrated in softer sites owing to the low focal depth of the site, topographical effects, and high frequency range of the mainshocks.

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