Consistent Scaling Laws for Thrusting Environment

2018 ◽  
Vol 9 (2) ◽  
pp. 46-62
Author(s):  
Sunil Kumar ◽  
M.L. Sharma ◽  
Josodhir Das
Keyword(s):  
Present Article ◽  
Entire Range ◽  
Scaling Laws ◽  
Moment Magnitude ◽  
Fault Rupture ◽  
Empirical Relationships ◽  
Lower Range ◽  
Rupture Length ◽  
Rupture Area ◽  
Self Consistent

The main objective of the present article is to develop self-consistent empirical relationships between rupture parameters and moment magnitude for the Himalayas. The database includes the fault rupture parameters of significant earthquakes in the Himalayan region and thrusting earthquakes from NGA West-2 database. The existing empirical relationships between magnitude and rupture parameters are reviewed in view of their consistency. The consistent relationships between moment magnitude and rupture parameters are derived and compared with the existing such relationships. The comparison of the developed consistent relationships reveal that the rupture length was being underestimated in the range of magnitude from 7 to 8, whereas it was overestimated in the lower range of magnitudes using inconsistent empirical relationships. While rupture width was overestimated for the entire range of magnitudes using inconsistent relationships, the rupture area was underestimated for magnitude greater than 7.

Surface rupture of the Greendale Fault during the Darfield (Canterbury) earthquake, New Zealand

2010 ◽  
Vol 43 (4) ◽  
pp. 236-242 ◽  
Author(s):  
M. Quigley ◽  
R. Van Dissen ◽  
P. Villamor ◽  
N. Litchfield ◽  
D. Barrell ◽  
...  
Keyword(s):  
New Zealand ◽  
Ground Surface ◽  
Vertical Displacement ◽  
Fault Rupture ◽  
Surface Rupture ◽  
Framed Structures ◽  
Rupture Length ◽  
The North ◽  
Dextral Strike Slip ◽  
East West

The Mw 7.1 Darfield (Canterbury) earthquake of 4 September 2010 (NZST) was the first earthquake in New Zealand to produce ground-surface fault rupture since the 1987 Edgecumbe earthquake. Surface rupture of the previously unrecognised Greendale Fault during the Darfield earthquake extends for at least 29.5 km and comprises an en echelon series of east-west striking, left-stepping traces. Displacement is predominantly dextral strike-slip, averaging ~2.5 m, with maxima of ~5 m along the central part of the rupture. Maximum vertical displacement is ~1.5 m, but generally < 0.75 m. The south side of the fault has been uplifted relative to the north for ~80% of the rupture length, except at the eastern end where the north side is up. The zone of surface rupture deformation ranges in width from ~30 to 300 m, and comprises discrete shears, localised bulges and, primarily, horizontal dextral flexure. At least a dozen buildings were affected by surface rupture, but none collapsed, largely because most of the buildings were relatively flexible and robust timber-framed structures and because deformation was distributed over tens to hundreds of metres width. Many linear features, such as roads, fences, power lines, and irrigation ditches were offset or deformed by fault rupture, providing markers for accurate determinations of displacement.

scholarly journals Use of remote sensing and seismotectonic parameters for seismic hazard analysis of Bangalore

2006 ◽  
Vol 6 (6) ◽  
pp. 927-939 ◽  
Author(s):  
T. G. Sitharam ◽  
P. Anbazhagan ◽  
K. Ganesha Raj
Keyword(s):  
Remote Sensing ◽  
Seismic Hazard ◽  
Ground Motion ◽  
Hazard Analysis ◽  
Seismic Hazard Analysis ◽  
Moment Magnitude ◽  
Seismic Zone ◽  
Fault Rupture ◽  
Maximum Credible Earthquake ◽  
Different Sources

Abstract. Deterministic Seismic Hazard Analysis (DSHA) for the Bangalore, India has been carried out by considering the past earthquakes, assumed subsurface fault rupture lengths and point source synthetic ground motion model. The sources have been identified using satellite remote sensing images and seismotectonic atlas map of India and relevant field studies. Maximum Credible Earthquake (MCE) has been determined by considering the regional seismotectonic activity in about 350 km radius around Bangalore. The seismotectonic map has been prepared by considering the faults, lineaments, shear zones in the area and past moderate earthquakes of more than 470 events having the moment magnitude of 3.5 and above. In addition, 1300 number of earthquake tremors having moment magnitude of less than 3.5 has been considered for the study. Shortest distance from the Bangalore to the different sources is measured and then Peak Horizontal Acceleration (PHA) is calculated for the different sources and moment magnitude of events using regional attenuation relation for peninsular India. Based on Wells and Coppersmith (1994) relationship, subsurface fault rupture length of about 3.8% of total length of the fault shown to be matching with past earthquake events in the area. To simulate synthetic ground motions, Boore (1983, 2003) SMSIM programs have been used and the PHA for the different locations is evaluated. From the above approaches, the PHA of 0.15 g was established. This value was obtained for a maximum credible earthquake having a moment magnitude of 5.1 for a source Mandya-Channapatna-Bangalore lineament. This particular source has been identified as a vulnerable source for Bangalore. From this study, it is very clear that Bangalore area can be described as seismically moderately active region. It is also recommended that southern part of Karnataka in particular Bangalore, Mandya and Kolar, need to be upgraded from current Indian Seismic Zone II to Seismic Zone III. Acceleration time history (ground motion) has been generated using synthetic earthquake model by considering the revised regional seismotectonic parameters. The rock level PHA map for Bangalore has been prepared and these maps are useful for the purpose of seismic microzonation, ground response analysis and design of important structures.

Magnetotelluric imaging of the fault rupture area of the 1999 İzmit (Turkey) earthquake

2005 ◽  
Vol 150 (1-3) ◽  
pp. 213-225 ◽  
Author(s):  
S. Bülent Tank ◽  
Yoshimori Honkura ◽  
Yasuo Ogawa ◽  
Masaki Matsushima ◽  
Naoto Oshiman ◽  
...  
Keyword(s):  
Fault Rupture ◽  
Rupture Area ◽  
Magnetotelluric Imaging

scholarly journals Intentionality, evil, God, and necessity

2020 ◽  
Vol 56 (3) ◽  
pp. 436-446
Author(s):  
AMIR HOROWITZ
Keyword(s):  
Present Article ◽  
Problem Of Evil ◽  
Logical Problem ◽  
Self Consistent

AbstractIn an article in this issue, Kenneth Pearce suggests a novel solution to the ‘logical problem of evil’. That is, he defends the consistency of the obtaining of evil with the existence of an omnipotent and good creator. The basic idea of Pearce's solution to the logical problem of evil is that according to the teleological theory of intentionality, which is self-consistent and consistent with the claim that God exists, some evil is necessary for the existence of created minds, and this evil is outweighed by the good that is involved in the existence of created minds. The present article argues that this suggestion fails to solve the problem.

Modeling of source rupture characteristics for the Saguenay earthquake of November 1988

1995 ◽  
Vol 85 (2) ◽  
pp. 525-551 ◽  
Author(s):  
R. A. W. Haddon
Keyword(s):  
North America ◽  
Stress Drop ◽  
High Stress ◽  
Strong Motion ◽  
Eastern North America ◽  
Fault Rupture ◽  
Rupture Area ◽  
Past Half Century ◽  
Acceleration Data ◽  
Strong Ground

Abstract The magnitude mb = 6.0 Saguenay earthquake of 25 November 1988 in Quebec, Canada, was one of the largest to have occurred in eastern North America during the past half-century. Recorded high-frequency ground motions exceeded anticipated values for an event of its size by a factor of 10 on both the regional network and strong-motion instruments. Two proposed explanations for the discrepancy are (1) that the source was a rare “high stress drop” event and (2) that it was an asymmetrical “fractional stress drop” rupture (involving only normal effective stresses). In this article, detailed fault-slip models are derived to fit characteristics of strong-motion displacement, velocity, and acceleration data. The results establish that the effective rupture stress was normal (less than 100 bars), that the fault rupture was highly asymmetrical with respect to the point of rupture initiation, and that the average slip time for points within the rupture area (approx. 0.2 sec) was considerably less than that associated with the standard Brune (1970) source spectral model. The rupture area developed in a number of episodes, each widening or lengthening the previously ruptured area, which may explain the short average slip time. The results indicate that the widely used assumption in hazard analyses that earthquake spectra are adequately represented by the standard Brune (1970) complete stress drop model may be seriously unreliable for prediction of strong ground motion in eastern North America.

scholarly journals Effects of self-consistent rest-ultraviolet colours in semi-empirical galaxy formation models

2020 ◽  
Vol 498 (2) ◽  
pp. 2645-2661 ◽  
Author(s):  
Jordan Mirocha ◽  
Charlotte Mason ◽  
Daniel P Stark
Keyword(s):  
Galaxy Formation ◽  
Surface Density ◽  
Empirical Relationships ◽  
James Webb Space Telescope ◽  
Luminosity Functions ◽  
Self Consistent ◽  
The Mean ◽  
Semi Empirical ◽  
Ir Emission ◽  
Dust Surface

ABSTRACT Connecting the observed rest-ultraviolet (UV) luminosities of high-z galaxies to their intrinsic luminosities (and thus star formation rates, SFRs) requires correcting for the presence of dust. We bypass a common dust-correction approach that uses empirical relationships between infrared (IR) emission and UV colours, and instead augment a semi-empirical model for galaxy formation with a simple – but self-consistent – dust model and use it to jointly fit high-z rest-UV luminosity functions (LFs) and colour–magnitude relations (MUV–β). In doing so, we find that UV colours evolve with redshift (at fixed UV magnitude), as suggested by observations, even in cases without underlying evolution in dust production, destruction, absorption, or geometry. The observed evolution in our model arises due to the reduction in the mean stellar age and rise in specific SFRs with increasing z. The UV extinction, AUV, evolves similarly with redshift, though we find a systematically shallower relation between AUV and MUV than that predicted by IRX–β relationships derived from z ∼ 3 galaxy samples. Finally, assuming that high $1600\hbox{-}{\mathring{\rm A}}$ transmission (≳0.6) is a reliable Ly α emitter (LAE) indicator, modest scatter in the effective dust surface density of galaxies can explain the evolution both in MUV–β and LAE fractions. These predictions are readily testable by deep surveys with the James Webb Space Telescope.

Holocene Rupture History of the Central Teton Fault at Leigh Lake, Grand Teton National Park, Wyoming

2019 ◽  
Vol 110 (1) ◽  
pp. 67-82 ◽  
Author(s):  
Mark S. Zellman ◽  
Christopher B. DuRoss ◽  
Glenn D. Thackray ◽  
Stephen F. Personius ◽  
Nadine G. Reitman ◽  
...  
Keyword(s):  
National Park ◽  
Optically Stimulated Luminescence ◽  
Early Holocene ◽  
Fault Rupture ◽  
Elapsed Time ◽  
Rupture Length ◽  
Open Questions ◽  
History Of ◽  
Teton Range ◽  
Lake Site

ABSTRACT Prominent scarps on Pinedale glacial surfaces along the eastern base of the Teton Range confirm latest Pleistocene to Holocene surface-faulting earthquakes on the Teton fault, but the timing of these events is only broadly constrained by a single previous paleoseismic study. We excavated two trenches at the Leigh Lake site near the center of the Teton fault to address open questions about earthquake timing and rupture length. Structural and stratigraphic evidence indicates two surface-faulting earthquakes at the site that postdate deglacial sediments dated by radiocarbon and optically stimulated luminescence to ∼10–11  ka. Earthquake LL2 occurred at ∼10.0  ka (9.7–10.4 ka; 95% confidence range) and LL1 at ∼5.9  ka (4.8–7.1 ka; 95%). LL2 predates an earthquake at ∼8  ka identified in the previous paleoseismic investigation at Granite Canyon. LL1 corresponds to the most recent Granite Canyon earthquake at ∼4.7–7.9  ka (95% confidence range). Our results are consistent with the previously documented long-elapsed time since the most recent Teton fault rupture and expand the fault’s earthquake history into the early Holocene.

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