scholarly journals Triggering mechanisms of soil instability

2006 ◽  
Author(s):  
A. Daouadji ◽  
H. Al Gali ◽  
F. Darve
Keyword(s):  
Triggering Mechanisms ◽  
Soil Instability

Quasar host galaxies and environments in the GAMA survey

2019 ◽  
Vol 15 (S356) ◽  
pp. 170-170
Author(s):  
Jari Kotilainen
Keyword(s):  
Galaxy Evolution ◽  
Large Scale ◽  
Group Membership ◽  
Host Galaxy ◽  
Host Galaxies ◽  
Cluster Group ◽  
First Results ◽  
Triggering Mechanisms ◽  
Mass Assembly

AbstractWe present first results from our study of the host galaxies and environments of quasars in Galaxy And Mass Assembly (GAMA), a multiwavelength photometric and spectroscopic survey for ∼300,000 galaxies over ∼300 deg2, to a limiting magnitude of r ∼ 20 mag. We use a GAIA-selected sample of ∼350 quasars at z < 0.3 in GAMA. For all the quasars, we determine all surrounding GAMA galaxies and measure their star formation (SF) rate and SF history, and the host galaxy morphology and group membership of the quasars. As a comparison sample of inactive galaxies, we use 1000 subsets of galaxies in GAMA, matched in redshift and galaxy stellar mass to the quasars. We find that quasar activity does not depend on the large-scale environment (cluster/group/void), although quasars tend to prefer satellite location in their environment. Compared to inactive galaxies, quasars are preferentially hosted in bulge-dominated galaxies and have higher SF rates, both overall and averaged over the last 10 and 100 Myr. Quasars also have shorter median SF timescales, shorter median time since the last SF burst, and higher metallicity than inactive galaxies. We discuss these results in terms of triggering mechanisms of the quasar activity and the role of quasars in galaxy evolution.

scholarly journals Spectropolarimetric Observation of an Emerging Flux Region: Triggering Mechanisms of Ellerman Bombs

2008 ◽  
Vol 684 (1) ◽  
pp. 736-746 ◽  
Author(s):  
H. Watanabe ◽  
R. Kitai ◽  
K. Okamoto ◽  
K. Nishida ◽  
J. Kiyohara ◽  
...  
Keyword(s):  
Triggering Mechanisms ◽  
Ellerman Bombs

Triggering mechanisms in microsaccade and saccade generation: a novel proposal

2011 ◽  
Vol 1233 (1) ◽  
pp. 107-116 ◽  
Author(s):  
Jorge Otero-Millan ◽  
Stephen L. Macknik ◽  
Alessandro Serra ◽  
R. John Leigh ◽  
Susana Martinez-Conde
Keyword(s):  
Triggering Mechanisms ◽  
Saccade Generation

Variations of the earthquake diffusion rates in the Western Gulf of Corinth (Greece)

2021 ◽  
Author(s):  
Georgios Michas ◽  
Vasilis Kapetanidis ◽  
George Kaviris ◽  
Filippos Vallianatos
Keyword(s):  
Fluid Pressure ◽  
Stress Transfer ◽  
The European Union ◽  
Triggering Mechanism ◽  
Development Education ◽  
Seismic Sequences ◽  
Gulf Of Corinth ◽  
Aftershock Sequences ◽  
Triggering Mechanisms ◽  
Diffusion Rates

&lt;p&gt;Earthquake diffusion is frequently observed in the spatiotemporal evolution of seismic clusters and regional seismicity, a characteristic that is attributed to a triggering mechanism, such as fluid flow, aseismic creep and/or stress transfer effects. In this work, we study the earthquake diffusion properties in the Western Gulf of Corinth (central Greece), an area that presents high extension rates, moderate to large magnitude earthquakes, intense microseismicity and frequent seismic swarms. We focus on the period 2013&amp;#8211;2014 that is characterized by intense background microseismic activity along with significant seismic sequences. More specifically, the latter include the 2013 Helike swarm, the 2014 seismic sequence between Nafpaktos and Psathopyrgos, which culminated with an Mw 4.9 event on 21 September 2014, as well as moderate magnitude events that were followed by aftershock sequences. In the herein analysis, we employ a relocated earthquake catalogue of ~9000 events which delineates the activated areas during the study period in high-resolution. We consider the most significant seismic sequences and calculate their respective spatial correlation histograms and the evolution of the mean squared distance of the hypocenters with time, in order to study the earthquake diffusion rates and possible variations that might be related to the triggering mechanisms of seismicity. Our results demonstrate a weak earthquake diffusion process, analogous to subdiffusion within a stochastic framework, for the seismic sequences under consideration, providing further evidence for slow earthquake diffusion in regional and global seismicity. In addition, the earthquake diffusion rates exhibit variations that can be associated with the triggering mechanism. In particular, seismic sequences which are related with pore-fluid pressure diffusion present considerably higher diffusion rates than mainshock/aftershock sequences or the background activity. Such results may provide novel constraints on the triggering mechanisms of clustered seismic activity based on the study of the earthquake diffusion rates.&amp;#160;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Acknowledgements&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;We would like to thank the personnel of the Hellenic Unified Seismological Network (http://eida.gein.noa.gr/) and the Corinth Rift Laboratory Network (https://doi.org/10.15778/RESIF.CL) for the installation and operation of the stations used in the current article. The present research is co-financed by Greece and the European Union (European Social Fund- ESF) through the Operational Programme &amp;#171;Human Resources Development, Education and Lifelong Learning 2014-2020&amp;#187; in the context of the project &amp;#8220;The role of fluids in the seismicity of the Western Gulf of Corinth (Greece)&amp;#8221; (MIS 5048127).&lt;/p&gt;

scholarly journals The Development of a 1-D Integrated Hydro-Mechanical Model Based on Flume Tests to Unravel Different Hydrological Triggering Processes of Debris Flows

Water ◽  
2018 ◽  
Vol 10 (7) ◽  
pp. 950 ◽  
Author(s):  
Theo van Asch ◽  
Bin Yu ◽  
Wei Hu
Keyword(s):  
Debris Flow ◽  
Mechanical Model ◽  
Debris Flows ◽  
Overland Flow ◽  
Slope Angle ◽  
Great Influence ◽  
Flume Experiments ◽  
Triggering Mechanisms ◽  
Bed Material ◽  
Triggering Process

Many studies which try to analyze conditions for debris flow development ignore the type of initiation. Therefore, this paper deals with the following questions: What type of hydro-mechanical triggering mechanisms for debris flows can we distinguish in upstream channels of debris flow prone gullies? Which are the main parameters controlling the type and temporal sequence of these triggering processes, and what is their influence on the meteorological thresholds for debris flow initiation? A series of laboratory experiments were carried out in a flume 8 m long and with a width of 0.3 m to detect the conditions for different types of triggering mechanisms. The flume experiments show a sequence of hydrological processes triggering debris flows, namely erosion and transport by intensive overland flow and by infiltrating water causing failure of channel bed material. On the basis of these experiments, an integrated hydro-mechanical model was developed, which describes Hortonian and saturation overland flow, maximum sediment transport, through flow and failure of bed material. The model was calibrated and validated using process indicator values measured during the experiments in the flume. Virtual model simulations carried out in a schematic hypothetical source area of a catchment show that slope angle and hydraulic conductivity of the bed material determine the type and sequence of these triggering processes. It was also clearly demonstrated that the type of hydrological triggering process and the influencing geometrical and hydro-mechanical parameters may have a great influence on rainfall intensity-duration threshold curves for the start of debris flows.

scholarly journals ANALISIS RUMAH KABEL BAWAH TANAH PADA PROYEK PEKERJAAN JARINGAN UTILITAS SKTT 150 KV PLUMPANG - GAMBIR

2018 ◽  
Vol 6 (2) ◽  
pp. 61-70
Author(s):  
Redaksi Tim Jurnal
Keyword(s):  
Carrying Capacity ◽  
Distribution Channel ◽  
Distribution Channels ◽  
Research Data ◽  
Land Acquisition ◽  
Shear Stability ◽  
Cable Networks ◽  
Underground Cable ◽  
The Stability ◽  
Soil Instability

Underground cable distribution channels to be excellent especially in big cities like Jakarta. This is because the underground cable distribution is a solution to the difficulty of land acquisition that will be used for top cable networks. Nevertheless, there is an important factor to be considered in implementing the underground cable distribution channel that is the condition of the soil through which the cable. This study aims to determine the dimensions of the cable house was safe from the soil instability. The soil instability are the stability of bolsters and the shear stability and take into account the carrying capacity of the foundation used. The data used as a reference in the analysis using research data that has been done previously. In stability analysis and foundation bearing capacity used Geo5 software demo version aid. The results obtained from the analysis, with variations on the dimensions of the cable house used are 2 mx 2 m, 2.5 mx 2.5 m and 3 mx 3 m, it is seen that the greater the dimensions used then the security number of stability bolsters, soil shear stability and the carrying capacity of the foundation decreases. This is due to the greater the dimensions of the cable house used, the greater the burden borne by the soil.

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