Seismic activity and structural features in the Charlevoix region, Quebec

1987 ◽  
Vol 24 (11) ◽  
pp. 2118-2129 ◽  
Author(s):  
Maurice Lamontagne
Keyword(s):  
Seismic Activity ◽  
Impact Crater ◽  
Time Window ◽  
Fault System ◽  
Earthquake Risk ◽  
Earthquake Activity ◽  
Seismic Zone ◽  
Nodal Solutions ◽  
Data Set ◽  
The Impact

The Charlevoix region is historically the most active earthquake zone in eastern Canada. Understanding the links between its seismicity and the faults of the region is important for the assessment of earthquake risk along the St. Lawrence Valley. The region has been monitored by a microseismic array since 1977, yielding accurate locations of the hypocentres. Previous analyses of data from the array indicated a relationship between the earthquakes and the St. Lawrence Valley paleorift faults. As a sequel to previous studies, the relationships between the seismic activity and the faults of the region were reexamined through the use of the composite P-nodal solutions, in an effort to clarify the nature of faulting in the seismic zone. The microseisms were partitioned into subsets of events on the basis of geological and hypocentre-trend considerations. The main objectives of this paper are to delineate the details of faulting within the Charlevoix region and to determine the effect of the impact crater on the nature of faulting in this area.Assuming a constant 6.2 km/s velocity model and using a data set of 107 events, composite fault-plane solutions were computed. The composite P-nodal solutions indicated that the Charlevoix impact crater modifies to a certain extent the focal-mechanism characteristics. Events outside the impact crater were found to be quite consistent in their polarity distribution on the focal sphere, suggesting similarity in their focal mechanisms. The composite mechanism of these events suggests a relationship between the earthquakes and the north–south faults mapped outside the impact crater. The magnitude mb (Lg) 5.0 earthquake of August 19, 1979, the largest event in the selected time window, had different fault planes than some of its aftershocks. Nevertheless, the polarity distribution of the aftershocks was in agreement with the average trend for the events outside the crater. Events inside the impact crater were found to be produced along more variable fault orientations, with an average trend similar to that of the rift fault system. It is proposed that the meteor impact weakened the rift faults and introduced its own fractures. The present earthquake activity probably occurs along these weak fault surfaces. The effect of the impact crater on the type of faulting versus depth is not readily discernible from available data. In general, meteor impacts do not leave neotectonic seismic signatures: the Charlevoix impact crater might represent a different case because of the presence of weakened paleorift faults.

Four steps to standardize reporting of peritoneal dialysis technique failure: A proposed approach

2020 ◽  
pp. 089686082097693
Author(s):  
Alix Clarke ◽  
Pietro Ravani ◽  
Matthew J Oliver ◽  
Mohamed Mahsin ◽  
Ngan N Lam ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Outcome Measure ◽  
Time Window ◽  
Time Windows ◽  
Dialysis Patients ◽  
Data Set ◽  
The Impact ◽  
Technique Failure ◽  
Standardize Reporting ◽  
Dialysis Technique

Background: Technique failure is an important outcome measure in research and quality improvement in peritoneal dialysis (PD) programs, but there is a lack of consistency in how it is reported. Methods: We used data collected about incident dialysis patients from 10 Canadian dialysis programs between 1 January 2004 and 31 December 2018. We identified four main steps that are required when calculating the risk of technique failure. We changed one variable at a time, and then all steps, simultaneously, to determine the impact on the observed risk of technique failure at 24 months. Results: A total of 1448 patients received PD. Selecting different cohorts of PD patients changed the observed risk of technique failure at 24 months by 2%. More than one-third of patients who switched to hemodialysis returned to PD—90% returned within 180 days. The use of different time windows of observation for a return to PD resulted in risks of technique failure that differed by 16%. The way in which exit events were handled during the time window impacted the risk of technique failure by 4% and choice of statistical method changed results by 4%. Overall, the observed risk of technique failure at 24 months differed by 20%, simply by applying different approaches to the same data set. Conclusions: The approach to reporting technique failure has an important impact on the observed results. We present a robust and transparent methodology to track technique failure over time and to compare performance between programs.

scholarly journals "Real time analysis" of the ion density measured by the satellite DEMETER in relation with the seismic activity

2012 ◽  
Vol 12 (9) ◽  
pp. 2957-2963 ◽  
Author(s):  
M. Li ◽  
M. Parrot
Keyword(s):  
Seismic Activity ◽  
False Alarms ◽  
Seismic Zone ◽  
Data Set ◽  
Ion Density ◽  
Real Time Analysis ◽  
Number Of False Alarms ◽  
Future Earthquake ◽  
Automatic Search ◽  
Seismic Area

Abstract. This paper is related to the study of the ion density recorded by the low altitude satellite DEMETER. In a first time there is an automatic search for ionospheric perturbations in the complete satellite data set of ion densities. Then perturbations due to known ionospheric phenomena (for example, solar activity) are eliminated as well as perturbations not above a seismic zone. In a second time, there is a search to know if each selected perturbation corresponds to a future earthquake. The earthquakes have been classified depending on their magnitude and depth. This attempt to predict earthquakes of course generates false alarms and wrong detections. The results of this statistical analysis are presented as function of various parameters. It is shown that the number of false alarms is very important, because the ionosphere has variations not only linked to the seismic activity. The number of wrong detections is also important and can be explained by the fact that the satellite is above a seismic area only a few minutes per day and we do not expect continuous perturbations from a given earthquake. The more important results of this study is that the ratio between detected earthquakes and earthquakes to be detected increases with the magnitude of the earthquakes which intuitively makes sense.

scholarly journals Modelling the impact of earthquake activity on real estate values: a multi-level approach

2017 ◽  
Vol 10 (1) ◽  
pp. 73-90 ◽  
Author(s):  
Berna Keskin ◽  
Richard Dunning ◽  
Craig Watkins
Keyword(s):  
Real Estate ◽  
Perceived Risk ◽  
House Prices ◽  
Insurance Companies ◽  
Earthquake Risk ◽  
Earthquake Activity ◽  
Content Type ◽  
Multi Level ◽  
Environmental Events ◽  
The Impact

Purpose This paper aims to explore the impact of a recent earthquake activity on house prices and their spatial distribution in the Istanbul housing market. Design/methodology/approach The paper uses a multi-level approach within an event study framework to model changes in the pattern of house prices in Istanbul. The model allows the isolation of the effects of earthquake risk and explores the differential impact in different submarkets in two study periods – one before (2007) and one after (2012) recent earthquake activity in the Van region, which although in Eastern Turkey served to alter the perceptions of risk through the wider geographic region. Findings The analysis shows that there are variations in the size of price discounts in submarkets resulting from the differential influence of a recent earthquake activity on perceived risk of damage. The model results show that the spatial impacts of these changes are not transmitted evenly across the study area. Rather it is clear that submarkets at the cheaper end of the market have proportionately larger negative impacts on real estate values. Research limitations/implications The robustness of the models would be enhanced by the addition of further spatial levels and larger data sets. Practical implications The methods introduced in this study can be used by real estate agents, valuers and insurance companies to help them more accurately assess the likely impacts of changes in the perceived risk of earthquake activity (or other environmental events such as flooding) on the formation of house prices in different market segments. Social implications The application of these methods is intended to inform a fairer approach to setting insurance premiums and a better basis for determining policy interventions and public investment designed to mitigate potential earthquake risk. Originality/value The paper represents an attempt to develop a novel extension of the standard use of hedonic models in event studies to investigate the impact of natural disasters on real estate values. The value of the approach is that it is able to better capture the granularity of the spatial effects of environmental events than the standard approach.

scholarly journals The recent tectonic stress field of the Amur region

2018 ◽  
Vol 9 (3) ◽  
pp. 1025-1037
Author(s):  
D. A. Safonov
Keyword(s):  
Stress Field ◽  
Seismic Activity ◽  
Tectonic Stress ◽  
Amur Region ◽  
Fault System ◽  
Tectonic Stress Field ◽  
Eastern Flank ◽  
The North ◽  
Tanlu Fault Zone ◽  
The Impact

The Amur region (Priamurie) is located in the NE part of the Amur lithospheric plate and its surrounding territories. Seismic activity is moderate in Priamurie, and the regional earthquakes, including the strongest ones, occur mainly in three seismic belts: Stanovoi (the zone of influence of the eastern flank of the Stanovoi fault), Yankan-Tukuringra-Soktakhan (the eastern flank of the Mongolia-Okhotsk lineament), and Turan-Selemzhinsky (from the Lesser Khingan to the north). The Sakhalin Branch of FRC GS RAS Catalogue of focal mechanisms of 57 regional earthquakes provide the data for a more precise estimation of the parameters of the crustal stress state in the study area. The Cataclastic Analysis Method (CAM) developed by Yu.L. Rebetsky (stage 1) was used to estimate the orientations of the main axes of the stress tensor and the Lode – Nadai coefficient. The analysis shows that the Upper Priamurie is dominated by shearing and compression with shearing. The Amur plate moves relative to the Aldan-Stanovoi block along the South Tukuringra and North Tukuringa faults to the east. Vertical shearing is predominant along the Dzheltulak fault and the western segment of the North Tukuringra fault. The NNE-trending compression takes place in the area located east of the quiescence zone of the Dzhagda ridge. Along the Mongolia-Okhotsk fault system, near the Sea of Okhotsk, the direction of compression changes to the northward one. The tectonic stress field along the Tanlu fault zone is inhomogeneous and comprises the alternating zones of horizontal compression and stretching with varying directions of the main stress axes. To the east of the band characterized by the maximum seismic activity, compression changes its direction to the southeast- and eastward. Probably, the impact of the oceanic subduction on the northern part of the Japan-Korean block begins to manifest itself in this part of the Amur region. The tectonic stress field reconstructed from the seismological data is consistent with the measurements of the modern crustal movements. The results of our study can prove useful for clarifying the tectonics of the region. 

Synthesis of Recent Paleoseismic Research on Quaternary Faulting in the Eastern Tennessee Seismic Zone, Eastern North America: Implications for Seismic Hazard and Intraplate Seismicity

2022 ◽  
Author(s):  
Randel Tom Cox ◽  
Robert D. Hatcher ◽  
Steven L. Forman ◽  
Ronald Counts ◽  
James Vaughn ◽  
...  
Keyword(s):  
North America ◽  
Seismic Activity ◽  
Plate Boundary ◽  
Thrust Fault ◽  
Normal Faults ◽  
Earthquake Activity ◽  
Intraplate Seismicity ◽  
Seismic Zone ◽  
Basement Fault ◽  
Eastern Tennessee Seismic Zone

ABSTRACT Causes of intraplate seismicity remain a great unsolved problem, in contrast with plate-boundary seismicity. Modern seismicity records frequent seismic activity in plate-boundary seismic zones, but in fault zones where seismic activity is not frequent, plate boundary or intraplate, resolution of prehistoric earthquake activity is critical for estimating earthquake recurrence interval and maximum expected magnitude. Thus, documenting prehistoric earthquakes is crucial for assessing earthquake hazard posed to infrastructure, including nuclear reactors and large dams. The ∼400 km long eastern Tennessee seismic zone (ETSZ), United States, is the third most active seismic zone east of the Rocky Mountains in North America, although the largest recorded ETSZ earthquake is only Mw 4.8. Ironically, it is the least studied major eastern U.S. seismic zone. Recent ETSZ field surveys revealed an 80 km long, 060°-trending corridor containing northeast-striking Quaternary thrust, strike slip, and normal faults with displacements ≥1 m. It partially overlaps a parallel trend of seismicity that extends 30 km farther southwest, suggesting this active faulting zone may extend ∼110 km within part of the ETSZ. Near Dandridge, Tennessee, a thrust fault in French Broad River alluvium records two earthquakes in the last 40,000 yr. About 50 km southwest near Alcoa, Tennessee, a thrust fault cuts Little River alluvium and records two earthquakes between 15,000 and 10,000 yr ago. About 30 km farther southwest at Vonore, Tennessee, a thrust fault displaces bedrock ≥2 m over colluvium, and alluvium is normal faulted >2 m. This corridor, just west of the Blue Ridge escarpment, overlies a steep gradient in midcrustal S-wave velocities, consistent with a basement fault at hypocentral depths. The corridor faults may be connected to a basement fault or localized coseismic faults above a blind basement fault. Our current data suggest at least two Mw≥6.5 surface rupturing events in the last 40,000 yr.

scholarly journals Multidisciplinary co-operation in building design according to urbanistic zoning and seismic microzonation

2005 ◽  
Vol 5 (3) ◽  
pp. 397-411 ◽  
Author(s):  
M. Bostenaru Dan
Keyword(s):  
Urban Areas ◽  
Urban System ◽  
Building Design ◽  
Reciprocal Relationship ◽  
Earthquake Risk ◽  
Data Set ◽  
The Public ◽  
Restructuring Process ◽  
The Impact ◽  
The Town

Abstract. Research and practice in seismology and urban planning interfere concerning the impact of earthquakes on urban areas. The roles of sub-area wide or typological divisions of the town were investigated with the methodology of regression, regarding their contribution to urban earthquake risk management. The inductive data set comprised recovery, preparedness, mitigation and resilience planning. All timely constituted planning types are refound today as layers, as the zoning results are used by differently backgrounded actors: local authorities, civil protection, urban planners, civil engineers. In resilience planning, the urban system is complexly theoretised, then integratedly approached. The steady restructuring process of the urban organism is evident in a dynamic analysis. Although expressed materially, the "urban-frame" is realised spiritually, space adaptation being also social. A retrospective investigation of the role of resilient individual buildings within the urban system of Bucharest, Romania, was undertaken, in order to learn systemic lessons considering the street, an educational environment. (In)formation in the study and decision making process stay in a reciprocal relationship, both being obliged in the (in)formation of the public opinion. For a complete view on resilience, both zoning types, seismic and urbanistic, must be considered and through their superposition new sub-area wide divisions of the town appear, making recommendations according to the vulnerability of the building type.

Age at Exposure to Parental Suicide and the Subsequent Risk of Suicide in Young People

Crisis ◽  
2018 ◽  
Vol 39 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Kuan-Ying Lee ◽  
Chung-Yi Li ◽  
Kun-Chia Chang ◽  
Tsung-Hsueh Lu ◽  
Ying-Yeh Chen
Keyword(s):  
Young People ◽  
Proportional Hazards ◽  
Proportional Hazards Model ◽  
Cox Proportional Hazards ◽  
Cox Proportional Hazards Model ◽  
Birth Registry ◽  
Data Set ◽  
Parental Suicide ◽  
The Impact ◽  
Age At Exposure

Abstract. Background: We investigated the age at exposure to parental suicide and the risk of subsequent suicide completion in young people. The impact of parental and offspring sex was also examined. Method: Using a cohort study design, we linked Taiwan's Birth Registry (1978–1997) with Taiwan's Death Registry (1985–2009) and identified 40,249 children who had experienced maternal suicide (n = 14,431), paternal suicide (n = 26,887), or the suicide of both parents (n = 281). Each exposed child was matched to 10 children of the same sex and birth year whose parents were still alive. This yielded a total of 398,081 children for our non-exposed cohort. A Cox proportional hazards model was used to compare the suicide risk of the exposed and non-exposed groups. Results: Compared with the non-exposed group, offspring who were exposed to parental suicide were 3.91 times (95% confidence interval [CI] = 3.10–4.92 more likely to die by suicide after adjusting for baseline characteristics. The risk of suicide seemed to be lower in older male offspring (HR = 3.94, 95% CI = 2.57–6.06), but higher in older female offspring (HR = 5.30, 95% CI = 3.05–9.22). Stratified analyses based on parental sex revealed similar patterns as the combined analysis. Limitations: As only register-­based data were used, we were not able to explore the impact of variables not contained in the data set, such as the role of mental illness. Conclusion: Our findings suggest a prominent elevation in the risk of suicide among offspring who lost their parents to suicide. The risk elevation differed according to the sex of the afflicted offspring as well as to their age at exposure.

State Medical Boards' Perceptions of a Minimum Data Set and Current Practices for Collecting Physician Information

2013 ◽  
Vol 99 (4) ◽  
pp. 40-45 ◽  
Author(s):  
Aaron Young ◽  
Philip Davignon ◽  
Margaret B. Hansen ◽  
Mark A. Eggen
Keyword(s):  
Media Coverage ◽  
The United States ◽  
Minimum Data Set ◽  
Direct Patient Care ◽  
Physician Workforce ◽  
Data Set ◽  
Minimum Data ◽  
State Medical Boards ◽  
The Impact ◽  
Current Practices

ABSTRACT Recent media coverage has focused on the supply of physicians in the United States, especially with the impact of a growing physician shortage and the Affordable Care Act. State medical boards and other entities maintain data on physician licensure and discipline, as well as some biographical data describing their physician populations. However, there are gaps of workforce information in these sources. The Federation of State Medical Boards' (FSMB) Census of Licensed Physicians and the AMA Masterfile, for example, offer valuable information, but they provide a limited picture of the physician workforce. Furthermore, they are unable to shed light on some of the nuances in physician availability, such as how much time physicians spend providing direct patient care. In response to these gaps, policymakers and regulators have in recent years discussed the creation of a physician minimum data set (MDS), which would be gathered periodically and would provide key physician workforce information. While proponents of an MDS believe it would provide benefits to a variety of stakeholders, an effort has not been attempted to determine whether state medical boards think it is important to collect physician workforce data and if they currently collect workforce information from licensed physicians. To learn more, the FSMB sent surveys to the executive directors at state medical boards to determine their perceptions of collecting workforce data and current practices regarding their collection of such data. The purpose of this article is to convey results from this effort. Survey findings indicate that the vast majority of boards view physician workforce information as valuable in the determination of health care needs within their state, and that various boards are already collecting some data elements. Analysis of the data confirms the potential benefits of a physician minimum data set (MDS) and why state medical boards are in a unique position to collect MDS information from physicians.

The Impact of Green Labels on U.S. Hotel Net Operating Income: Operating Statements Analyses

2019 ◽  
Vol 11 (1) ◽  
pp. 156-173
Author(s):  
Spenser Robinson ◽  
A.J. Singh
Keyword(s):  
Environmental Design ◽  
Green Buildings ◽  
Small Sample ◽  
Sample Survey ◽  
Data Set ◽  
Operating Income ◽  
Energy Star ◽  
The Impact ◽  
Industry Professionals

This paper shows Leadership in Energy and Environmental Design (LEED) certified hospitality properties exhibit increased expenses and earn lower net operating income (NOI) than non-certified buildings. ENERGY STAR certified properties demonstrate lower overall expenses than non-certified buildings with statistically neutral NOI effects. Using a custom sample of all green buildings and their competitive data set as of 2013 provided by Smith Travel Research (STR), the paper documents potential reasons for this result including increased operational expenses, potential confusion with certified and registered LEED projects in the data, and qualitative input. The qualitative input comes from a small sample survey of five industry professionals. The paper provides one of the only analyses on operating efficiencies with LEED and ENERGY STAR hospitality properties.

Does Tax Increment Financing Pass the “But-for” Test in Missouri?

2019 ◽  
Vol 33 (3) ◽  
pp. 187-202
Author(s):  
Ahmed Rachid El-Khattabi ◽  
T. William Lester
Keyword(s):  
Economic Development ◽  
Kansas City ◽  
Time Series Data ◽  
Local Level ◽  
Conclusive Evidence ◽  
Series Data ◽  
Tax Increment Financing ◽  
Data Set ◽  
Development Indicators ◽  
The Impact

The use of tax increment financing (TIF) remains a popular, yet highly controversial, tool among policy makers in their efforts to promote economic development. This study conducts a comprehensive assessment of the effectiveness of Missouri’s TIF program, specifically in Kansas City and St. Louis, in creating economic opportunities. We build a time-series data set starting 1990 through 2012 of detailed employment levels, establishment counts, and sales at the census block-group level to run a set of difference-in-differences with matching estimates for the impact of TIF at the local level. Although we analyze the impact of TIF on a wide set of indicators and across various industry sectors, we find no conclusive evidence that the TIF program in either city has a causal impact on key economic development indicators.

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