SEDIMENTOLOGICAL SIGNATURES OF REGIONAL SEISMICITY IN WESTERN SHIKOKU, JAPAN

Detection capabilities of the Yellowknife seismic array and regional seismicity

Bulletin of the Seismological Society of America ◽

10.1785/bssa0610040993 ◽

1971 ◽

Vol 61 (4) ◽

pp. 993-1008

Author(s):

F. M. Anglin

Keyword(s):

Seismic Array ◽

Detection Level ◽

Array Data ◽

Regional Variations ◽

Regional Seismicity ◽

The Third ◽

Detection Capabilities ◽

The Mean

abstract Detection statistics from a search of 99 days of Yellowknife Array data have been obtained. The mean 50 and 90 per cent cumulative detection levels are found to be m 3.9 and m 4.2 for the third zone from Yellowknife. Regional variations in the detection levels have been found. The 50 per cent cumulative detection level ranges from m 3.8 for Asia to m 4.3 for the Aleutians. Regional values of the slopes of the recurrence curves for log N versus magnitude have been obtained, the mean slope for the third zone from Yellowknife being −0.99.

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Performance of a Post-Byzantine Triple-Domed Basilica under Near and Far Fault Seismic Loads

Handbook of Research on Seismic Assessment and Rehabilitation of Historic Structures - Advances in Civil and Industrial Engineering ◽

10.4018/978-1-4666-8286-3.ch028 ◽

2015 ◽

pp. 831-867 ◽

Cited By ~ 2

Author(s):

Constantine C. Spyrakos ◽

Charilaos A. Maniatakis ◽

Panagiotis Kiriakopoulos ◽

Alessio Francioso ◽

Ioannis M. Taflampas

Keyword(s):

Structural Damage ◽

New Technology ◽

Element Model ◽

Seismic Loads ◽

Regional Seismicity ◽

Near Fault ◽

Collapse Mechanisms ◽

Before And After ◽

Out Of Plane ◽

Structural Parts

In this Chapter a triple-domed basilica constructed at the end of the 19th century is selected as a case study to present a methodology for the selection of the appropriate intervention techniques in monumental structures. The methodology includes in-situ and laboratory testing, application of analytical methods, consideration of geotechnical parameters and regional seismicity. Seismic loads are estimated according to contemporary and older concepts for seismic design. Since the impact of near-fault phenomena on masonry structures has not been thoroughly studied, although considered as responsible for extensive structural damage during major seismic events, a procedure is presented in order to account for the special characteristics of strong ground motion, in the so-called near-fault region. The seismic performance of the structure before and after interventions, using traditional and new technology, is assessed by applying a validated finite element model. Also, the out-of-plane behavior of structural parts is evaluated through kinematic analysis of selective collapse mechanisms.

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Finite element-based probabilistic stability analysis of rock-fill tailing dam considering regional seismicity

Innovative Infrastructure Solutions ◽

10.1007/s41062-019-0223-2 ◽

2019 ◽

Vol 4 (1) ◽

Cited By ~ 1

Author(s):

A. Hegde ◽

Tanmoy Das

Keyword(s):

Finite Element ◽

Stability Analysis ◽

Regional Seismicity ◽

Rock Fill ◽

Tailing Dam

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Background seismicity and seismic monitoring in the Lai Chau reservoir area

Journal of Seismology ◽

10.1007/s10950-019-09875-6 ◽

2019 ◽

Vol 23 (6) ◽

pp. 1373-1390

Author(s):

Grzegorz Lizurek ◽

Jan Wiszniowski ◽

N. V. Giang ◽

D. Q. Van ◽

L. V. Dung ◽

...

Keyword(s):

Seismic Activity ◽

Moment Tensor ◽

Synthetic Data ◽

Seismic Monitoring ◽

Local Network ◽

Regional Seismicity ◽

Seismic Catalogue ◽

Reservoir Impoundment ◽

The Future ◽

Passive Seismic

Abstract Reservoir-triggered seismic activity depends not only on the technical characteristics of the future reservoir (filling volume, the height of water column) but also on the seismo-tectonics and the natural seismic processes occurring in the area before construction of an artificial reservoir. Passive seismic monitoring was realised near Lai Chau (Vietnam) before the impoundment started. It allowed exploration of the natural seismicity in the area of the future dam. Locations of seismic events several months prior to the reservoir impoundment were observed with ten stations installed in the reservoir vicinity. Events were mainly located near the dam along the Da river headwaters fault. However, only four stations were available for the entire period before the impoundment. Despite the network limitations, completeness of seismic catalogue and b value were determined and may be used as a baseline for analysis of the seismicity in this area after impoundment. The magnitude completeness level is significantly smaller than in the broader seismogenic zones covering an area of the dam. The b value differs from the results obtained for regional seismicity of Northeastern Vietnam. The capability of the local network for moment tensor inversion was estimated with the use of synthetic data tests. Test results provided the requirements for the station number according to azimuthal coverage of the network to obtain the reliable full moment tensor (MT) solution. Preliminary analysis of the seismic activity after Lai Chau reservoir impoundment indicates some changes in activity related to the impoundment and reservoir exploitation.

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Moho Variations across the Northern Canadian Cordillera

Seismological Research Letters ◽

10.1785/0220200166 ◽

2020 ◽

Vol 91 (6) ◽

pp. 3076-3085 ◽

Cited By ~ 1

Author(s):

Pascal Audet ◽

Derek L. Schutt ◽

Andrew J. Schaeffer ◽

Clément Estève ◽

Richard C. Aster ◽

...

Keyword(s):

Elevated Temperatures ◽

High Elevation ◽

Receiver Functions ◽

Moho Depth ◽

Canadian Cordillera ◽

Regional Seismicity ◽

Thermal Buoyancy ◽

Mackenzie Mountains ◽

Moho Depths ◽

Array Density

Abstract Moho morphology in orogens provides important constraints on the rheology and density structure of the crust and underlying mantle. Previous studies of Moho geometry in the northern Canadian Cordillera (NCC) using very sparse seismic data have indicated a flat and shallow (∼30–35 km) Moho, despite an average elevation of >1000 m above sea level attributable to increased thermal buoyancy and lower crustal flow due to elevated temperatures. We estimate Moho depth using receiver functions from an expanded dataset incorporating 173 past and recently deployed broadband seismic stations, including the EarthScope Transportable Array, Mackenzie Mountains transect, and other recent deployments. We determine Moho depths in the range 27–43 km, with mean and standard deviations of 33.0 and 3.0 km, respectively, and note thickened crust beneath high-elevation seismogenic regions. In the Mackenzie Mountains, thicker crust is interpreted as due to crustal stacking from thrust sheet emplacement. The edge of this region of thickened crust is interpreted to delineate the extent of the former Laurentian margin beneath the NCC and is associated with a transition from thrust to strike-slip faulting observed in regional seismicity. More geographically extensive seismograph deployments at EarthScope Transportable Array density and scale will be required to further extend crustal-scale and lithosphere-scale imaging in western Canada.

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