Felt Area Research Articles

Clinical significance of osmophobia and its effect on quality of life in people with migraine.

In this study, we aimed to evaluate the clinical significance of osmophobia and its effect on quality of life in people with migraine. A total of 145 people with migraine were included in this cross-sectional study. Patients were evaluated with the migraine data form, the Migraine 24-Hour Quality of Life Questionnaire (24-HrMQoLQ), the Migraine Disability Assessment Scale (MIDAS), the Patient Health Questionnaire-9 (PHQ-9), the Insomnia Severity Index (ISI), the Generalized Anxiety Disorder-7 (GAD-7), the Allodynia Symptom Checklist (ASC), and the Fatigue Severity Scale (FSS). To evaluate the presence of osmophobia retrospectively, a semi-structured interview was conducted with the patients by the neurologist. The mean 24-Hr-MQoLQ of patients with osmophobia was significantly lower than those without osmophobia. The decrease in the 24-Hr-MQoLQ was statistically significant in the areas of feeling and concerns and social functionality. The mean of the MIDAS scale was higher significantly in patients with osmophobia than those without osmophobia. In addition, the mean ISI, PHQ-9, FSS and ASC scores of patients with osmophobia were statistically significantly higher than those without osmophobia. Both 24-h and 3-month quality of life of people with migraine with osmophobia were more affected than those without osmophobia. At the same manner, insomnia, depression, fatigue and allodynia were observed at higher rates in people with migraine with osmophobia than in migraine without osmophobia. Osmophobia, which is one of the specific symptoms that distinguishes migraine from other headache disorders, deserves further and multifaceted investigation.

The 6 May 1947 Milwaukee, Wisconsin, Earthquake

AbstractThe State of Wisconsin is not known for earthquake activity. The authoritative public-facing U.S. Geological Survey Comprehensive Catalog of earthquakes includes only three small (magnitude < 2) earthquakes in the state, all instrumentally recorded. Although other catalogs include more events in Wisconsin, experience has shown that many types of events, such as explosions and cryoseisms, have made their way into earthquake catalogs in this region. In this short report, I summarize available information about an earthquake that was felt in eastern Wisconsin at 15:27 local time on 6 May 1947. As what appears to be the largest historical earthquake in the State of Wisconsin, it is of public interest, its modest size notwithstanding. It appears that no useful instrumental records exist, due in part to a teleseismic event that occurred approximately 3 min later, generating surface waves that were recorded on early long-period instruments in the region. Instrumental data may exist for this event but have not been found. Comparing the felt area with information from recent earthquakes in the region, I estimate an intensity magnitude of 3.8 for the event, with a subjectively estimated uncertainty range 3.5–4.1. Relatively strong effects, including reports of broken dishes in Milwaukee, and shaking described as short but especially sharp, suggest that the event may have been among the sprinkling of shallow earthquakes now known to occur in the upper Great Lakes region.

Assessment of Historical Earthquake Magnitudes and Epicenters Using Ground Motion Simulations

Historical records of earthquakes are generally used as a basis to extrapolate the instrumental earthquake catalog in time and space during the probabilistic seismic hazard analysis (PSHA). However, the historical catalogs’ input parameters determined through historical descriptions rather than any quantitative measurements are accompanied by considerable uncertainty in PSHA. Therefore, quantitative assessment to verify the historical earthquake parameters is essential for refining the reliability of PSHA. This study presents an approach and its application to constrain reliable ranges of the magnitude and corresponding epicenter of historical earthquakes. First, ranges rather than specific values of ground motion intensities are estimated at multiple locations with distances between each other for selected historical earthquakes by reviewing observed co-seismic natural phenomena, structural damage levels, or felt areas described in their historical records. Based on specific objective criteria, this study selects only one earthquake (July 24, 1643), which is potentially one of the largest historical earthquakes. Then, ground motion simulations are performed for sufficiently broadly distributed epicenters, with a regular grid to prevent one from relying on strong assumptions. Calculated peak ground accelerations and velocities in areas with the historical descriptions on corresponding earthquakes are converted to intensities with an empirical ground motion-intensity conversion equation to compare them with historical descriptions. For the ground motion simulation, ground motion prediction equations and a frequency- wavenumber method are used to consider the effects of possible source mechanisms and stress drop. From these quantitative calculations, reliable ranges of epicenters and magnitudes and the trade-off between them are inferred for the earthquake that can conservatively match the upper and lower boundaries of intensity values from historical descriptions.

Corporate Governance and Managing Stress in the Workplace

Stress has become a killer condition given the pressures and demands of our present times. More people are either laid low or dying from stress. Unfortunately, stress is a silent killer that strikes before its victim can realize what his problem is. Stress in the workplace adds additional load to an average worker who must grapple with the daily demands and pressure from the workplace. This paper explored the relationship between corporate governance and stress management in the workplace. An examination of available literature shows that factors in the work place that cause stress include work overload, time pressure, long hours of work, lack of breaks, difficult or complex tasks, lack of variety, poor physical work conditions (congested office space, high temperature, poor lighting, etc.), role ambiguity, role conflict, over promotion, under promotion, thwarted ambition, absence of job security, problem of relationship with superiors and colleagues, inability to delegate responsibilities, absence or insufficient participation in decision making, office politics, behavioural restrictions, absence of effective consultation and financial difficulties, generating of loud noise by machines. Signs of stress can exhibit in several forms such as changes in behaviour, which in acute cases displays in the areas of feelings, behaviour or physical symptoms. Acute stress can exhibit in the forms of irritability, anxiety, fatigue, depression, withdrawal, aggressive behaviour, tearfulness, dullness, loss of motivation, loss of concentration, loss of ability to solve problems, sexual dysfunction, gastrointestinal disorders, recurrent headache, etc. Prolonged cases of stress in an individual can alter the “neuroendocrine, cardiovascular, autonomic and immunological functions” of the body leading to physical and mental illness. It was established that management by way of corporate governance can formulate policies that are geared towards managing the level of stress in the workplace. The recommendations made included that management should do the following; make the work place employee-friendly by providing conducive work environment and office spaces; establish a culture of filial relationships in the organization whereby employees see one another as friends and team-mates and relate to one another in cordial and courteous manner; popularize the organizational work ethics and enforce strict disciplinary measures on defaulters especially on harassment of every kind; establish clear job responsibilities and roles to prevent role ambiguity and job conflict; establish recreational centres for workers to ease off during breaks or at free time; functional health facilities should be provided and workers should have ready access to them; encourage open communication between employees and superiors and among all workers.

The 1885 M 6.9 Earthquake in the French Guiana–Brazil Border: The Largest Midplate Event in the Nineteenth Century in South America

AbstractIn 4 August 1885, 06:30 local time, a strong earthquake (reported intensities up to VI–VII modified Mercalli intensity [MMI]) was felt in the French Guiana, causing slight damage. Recently discovered newspaper records show that this event was also felt as far as Georgetown (British Guyana), Belém, and several other localities along the Amazon River toward Manaus (Brazil). The distribution of intensities and the radius of the felt area indicate a magnitude around Mw 6.9, which makes it the largest known earthquake in the stable continental region of South America, since the nineteenth century. The epicenter, determined with four different attenuation relations, lies onshore near the border between the French Guiana and Brazil, although an epicenter offshore in the continental slope cannot be ruled out with 95% confidence. The epicenter (03.4° N, 52.9°W±100 km) likely lies in the Transamazonian (2.2–2.0 Ga) geochronological province in the Guyana shield of the Amazon craton. No nearby failed rift is known onshore near the epicenter, which would place this event in the ∼30% class of nonextended stable continental crust. Other nearby smaller earthquakes (both historical and instrumental) with magnitudes up to mb 5.2, indicate a cluster of seismicity in the region of the 1885 earthquake, possibly delineating an onshore seismic zone separate from the sparse seismicity along the continental shelf. This large midplate earthquake will likely affect future reevaluations of seismic hazard in midplate South America.

Rapid Learning of Earthquake Felt Area and Intensity Distribution with Real-time Search Engine Queries

Immediately after a destructive earthquake, the real-time seismological community has a major focus on rapidly estimating the felt area and the extent of ground shaking. This estimate provides critical guidance for government emergency response teams to conduct orderly rescue and recovery operations in the damaged areas. While considerable efforts have been made in this direction, it still remains a realistic challenge for gathering macro-seismic data in a timely, accurate and cost-effective manner. To this end, we introduce a new direction to improve the information acquisition through monitoring the real-time information-seeking behaviors in the search engine queries, which are submitted by tens of millions of users after earthquakes. Specifically, we provide a very efficient, robust and machine-learning-assisted method for mapping the user-reported ground shaking distribution through the large-scale analysis of real-time search queries from a dominant search engine in China. In our approach, each query is regarded as a “crowd sensor” with a certain weight of confidence to proactively report the shaking location and extent. By fitting the epicenters of earthquakes occurred in mainland China from 2014 to 2018 with well-designed machine learning models, we can efficiently learn the realistic weight of confidence for each search query and sketch the felt areas and intensity distributions for most of the earthquakes. Indeed, this approach paves the way for using real-time search engine queries to efficiently map earthquake felt area in the regions with a relatively large population of search engine users.

The Međimurje (Croatia) Earthquake of 1738

Abstract The 30 March 1738 earthquake with an epicenter near Čakovec in Međimurje (Croatia) is the largest known earthquake in the low-seismicity area that includes northernmost Croatia, northeastern Slovenia, southeastern Austria, and southwestern Hungary. So far, it has attracted very little attention in the seismological communities of those countries. It is missing or has wrong source parameters in all of the relevant earthquake catalogs (including the Seismic Hazard Harmonization in Europe (SHARE) catalog, Stucchi et al., 2013), which may influence seismic hazard assessment in this part of Europe, most critically in the Međimurje region itself. We present contemporary historical data shedding some light on the effects that the earthquake had on settlements mostly in Međimurje, but also elsewhere in Croatia, Slovenia, and Hungary. We were able to assign intensities to 12 localities surrounding the epicenter and to resolve the confusion about its date of occurrence. The intensity points were inverted for the location of the macroseismic hypocenter and epicentral intensity (I0=7.9 MSK [Medvedev–Sponheuer–Karnik]). The epicenter is found to lie on the hanging wall of the reverse Čakovec fault, about 6 km from its surface trace, and 8 km north-northwest of the town of Čakovec. The rather small felt area for an earthquake of this maximum intensity implies a shallow macroseismic focal depth of 6 km. These values of intensity and depth correspond to a macroseismic magnitude of MLm 5.1.

Seismic Intensity Attenuation for Intraplate Earthquakes in Brazil with the Re‐Evaluation of Historical Seismicity

ABSTRACTIntensity evaluation attempts to quantify a qualitative description of the effects observed in an earthquake ranked in terms of how strong it was felt and the amount of damage. Despite its qualitative nature, intensity data are essential to study both historical and recent earthquakes such as in earthquake hazard studies and in which dense accelerometric data are missing. The magnitude of historical earthquakes in Brazil has been determined with relations involving magnitude and felt area. Intensity attenuation equations (decay of intensity as a function of magnitude, depth, and distance) determined in other regions of the world are intrinsically dependent on the crustal tectonic characteristics and cannot be applied to Brazil without proper evaluation. We determined an intensity attenuation equation using 20 earthquakes in Brazil and neighboring intraplate areas, in the magnitude range mb 3.5–6.2 and hypocentral distances up to 720 km.The best attenuation model was I=0.995M−1.505logR−0.00116R+2.08 (standard deviation = 0.778), in which M is the magnitude (mb) and R is the hypocentral distance (in kilometers). The uncertainties of the estimated magnitudes using this equation are around mb±0.72 for events with 30 or more intensity points.We tested the new equation with intensity data from two important events: the 1939 offshore earthquake (mb 6) in southern Brazil and the 2018 Venezuela earthquake (mb 6.9). The fit was reasonable for both earthquakes, with a root mean square residual of 1.0 and 1.1 intensity units, respectively.We also re‐evaluated the 1861 earthquake in southeast Brazil. The new epicenter was 23.1° S 44.7° W with a magnitude of mb 5. The epicenter was located onshore, but the estimated uncertainties include a large offshore region. Given that, the location of the 1861 event remains uncertain.

Calibration and Validation of MEEP Method for Location and Magnitude Estimation of Historical Earthquakes from Intra-Carpathian Region of Romania

Intra-Carpathian Region of Romania experienced strong earthquakes as it is mentioned in the national and international databases, e.g. November 26, 1829 (Ms = 6.4), October 10, 1834 (Ms = 6.3), January 26, 1916 (Ms = 6.4), July 12, 1991 (Mw = 5.7). The paper focuses on calibration and validation of MEEP method (Macroseismic Estimation of Earthquake Parameters, Musson & Jimenez, 2008) to provide a homogeneous and repeatable procedure for processing intensity data points (IDPs) which may supply the location and magnitude Mw of historical earthquakes occurred in the Intra-Carpathian Region of Romania and surroundings. The MEEP method is based on 1) grid-search technique for locating the epicentres and 2) the felt area approach to estimate the magnitude. It has the advantage to be used for small and moderate events. We used two high-quality datasets of earthquakes of the 20th century for which macroseismic data points (IDPs), instrumental moment magnitude (Mw) and instrumental epicentral coordinates are available, one for calibration and the other one for validation of the method. The main parameters used through MEEP algorithm were calibrated at regional scale using high-quality instrumental data: 1) crustal attenuation Q3 = 435 (Q at f = 3 Hz, which is understood to be the limit of the human perception of seismic waves), 2) Kövesligethy’s inelastic attenuation (∝ = 0.0065), 3) isoseismic spacing coefficient (k = 3.1) and 4) C = 2015, a constant generally related to tectonic regime. The MEEP method was successfully tested for events occurred within extra-Carpathian regions and the Pannonian Basin.

App Earthquake Detection and Automatic Mapping of Felt Area

App Earthquake Detection and Automatic Mapping of Felt Area

Sismicidade do Nordeste do Brasil

ABSTRACTA revised catalogue of earthquakes, which occurred in the Northeastern region of Brazilup to 1980, is presented. Most of the data come from historical macroseismic informationcollected in old publications and newspapers. Recent instrumental data is used to deriveempirical relations between magnitude and felt area in order to estimate mb magnitudesfor the events not recorded by seismographic stations. Macroseismic data for two largeevents (Pereiro 23.02.68, and Pacajus 20.11.80) are presented in detail. Epicentres of fourrecent events recorded at NAT were determined by combining the macroseismic andinstrumental data and used to define a preliminary value of the ratio K=Vp/Vs = 1.77 forthe region under study. A swarm of activity at Parazinho, Rio Grande do Norte, wasstudied in more detail to estimate the parameter b of the Gutenberg and Richter frequency-relation.

Recent earthquakes in Denmark are felt over as large areas as earthquakes of similar magnitudes in the Fennoscandian Shield and East European Platform

For magnitude estimation of historical, pre-instrumental earthquakes it is useful to estimate felt areas for several intensities. From several macroseismic surveys it has been observed that an old shield such as the Fennoscandian Shield has especially large felt areas compared to California where the magnitude formula was developed. However, the newest Danish observations of felt areas and associated digitally determined magnitudes presented in this study show that the subsurface of Denmark has a response to shaking which is similar to that of the Fennoscandian Shield. This study covers the period 1996–2012 and includes an analysis of the macroseismic surveys of all felt earthquakes. Eight of these earthquakes provided new information on intensity areas in Denmark. An aim for the future is to use the felt areas of old earthquakes in Denmark for improved estimations of their magnitudes.

Exploiting the Demographics of “Did You Feel It?” Responses to Estimate the Felt Area of Moderate Earthquakes in California

ABSTRACT We combine “Did You Feel It?” (DYFI) responses with the populations of reporting and nonreporting ZIP codes to improve estimates of the lowest intensities (modified Mercalli intensity; 1≤MMI≤3) and the overall felt area for moderate earthquakes. We presume that participation in the DYFI website is sufficiently widespread to interpret shaking in nonreporting ZIP codes as “not felt.” For most moderate earthquakes, no nonreporting ZIP codes are located near the earthquake; reporting and nonreporting ZIP codes overlap over intermediate distances; and few reporting ZIP codes are located at regional distances. We combine the intensities from reporting and nonreporting ZIP codes by weighing the average intensity in each reporting ZIP code by the number of reports and by weighing the “not felt” intensity in each nonreporting ZIP code by the population/5000. We reduce the average intensities for underreporting ZIP codes, where the number of reports is less than the population/5000, to account for the nonreporting population. We refer to the combination of intensities from reporting, underreporting, and nonreporting ZIP codes as the revised community decimal intensity (CDI*) to distinguish it from the standard CDI of Wald et al. (1999). This revision significantly improves estimates of the lowest intensities. We contour the revised intensity distributions and interpret the CDI * =1.5 contour as the limit of the felt area. This contour is well determined in densely populated areas and adequately determined in sparsely populated areas.

Role of African–Eurasian plate setting in the felt areas of intermediate‐depth earthquakes: an investigation using crowdsourced data

AbstractGreek intermediate‐depth earthquakes, occurring in the subducted plate of the Hellenic Arc, are felt at greater distances than expected, reaching Italy in some cases. We study in detail macroseismic intensity data from intermediate‐depth Italian and Greek earthquakes collected from Internet users who felt the shaking in Italy. The huge amount of data allowed us to outline the felt/not‐felt limit and to find a correspondence between attenuation areas and the presence of asthenospheric material at shallow depths. We show that plate boundaries, known to produce the majority of earthquakes, are, in some specific cases, the boundaries of areas in which earthquakes are felt. The Ionian subducted lithosphere propagates seismic waves with low attenuation over large distances, whereas high‐attenuation zones in Italy, linked to asthenospheric upwelling, limit the propagation, as evidenced also by PGA values. We identify a typical pattern that can be used to recognize intermediate‐depth earthquakes, and to properly locate historical events.

A Rare Moderate‐Sized (Mw 4.9) Earthquake in Kansas: Rupture Process of the Milan, Kansas, Earthquake of 12 November 2014 and Its Relationship to Fluid Injection

The largest recorded earthquake in Kansas occurred northeast of Milan on 12 November 2014 ( M w 4.9) in a region previously devoid of significant seismic activity. Applying multistation processing to data from local stations, we are able to detail the rupture process and rupture geometry of the mainshock, identify the causative fault plane, and delineate the expansion and extent of the subsequent seismic activity. The earthquake followed rapid increases of fluid injection by multiple wastewater injection wells in the vicinity of the fault. The source parameters and behavior of the Milan earthquake and foreshock–aftershock sequence are similar to characteristics of other earthquakes induced by wastewater injection into permeable formations overlying crystalline basement. This earthquake also provides an opportunity to test the empirical relation that uses felt area to estimate moment magnitude for historical earthquakes for Kansas.

Valores del lider para la gestion de conflictos.

Empirical test: the intra and interpersonal instrumental leader's personal values, their beacons of light in the areas of thinking and attitudes and behavior, to manage the conflict to a functional approach; and personal values intrapersonal terminals, roots of his heart in the areas of feeling, lead to discovering the causes of conflict in intra and interpersonal dimensions.Palabras claves: conflicto, valores, compasiA³n, pensamiento y sentimiento.

Analysis on the Relationship between Intensity and Magnitude for Historical Earthquakes in the Korean Peninsula

Equations that could estimate the local magnitude of historical earthquakes, being difficult to calculate, in Sino-Korea craton was obtained using instrumental earthquake data for 22 Korean and 46 northeastern Chinese events. The obtained equations from intensity is . The equation from felt area FA for the Korean Peninsula is . When the information on earthquake damage, effects, and felt area is all recorded at the same time, the former equation of intensity is more feasible than that of felt area due to uncertainty in earthquake felt area.

On the footprints of a major Brazilian Amazon earthquake

Combining historical accounts and seismological studies, three hundred years of dormant information emerged as a source of the largest known seismic event that rocked Brazil since the beginning of our colonization. The probable epicenter location of the 1690 tremor lies on the left bank of the Amazon River, about 45 km downstream from the modern day Manaus. A year later, while passing this area, a missionary met witnesses of the tremor and observed remarkable changes in the topography and vegetation along the margin of the river. By 1692 another priest confirmed this event and the occurrence of large waves in the river, which led to the flooding of the Native Indians' terrains. The tremor spread seismic waves throughout the forest and shook indigenous constructions as far as one thousand kilometers away. A calculation of the seismic parameters shows an estimated magnitude of 7, a maximum intensity of IX MM and a felt area of about 2 million km2. Due to the long recurrence period for this type of tremor, the discovery of one of these events is valuable for seismic global intraplate studies. As for Brazil, it unravels the myth that the country was never hit by severe earthquakes.

A saga of the 1896 South Iceland earthquake sequence: magnitudes, macroseismic effects and damage

This paper describes Professor Ambraseys’s work on the quantification of magnitudes of the main events in the 1896 South Iceland earthquake sequence, using original teleseismic data recorded by primitive seismological instruments located in Russia and Italy. This includes an example of his original worksheets showing surface-wave magnitude re-appraisal along with the initial part of the parametric earthquake catalogue of Iceland. A brief description of the macroseismic effects of the earthquake sequence is presented. Earthquake damage to buildings in the most affected area is quantified as fractions of collapsed farmhouses. Spatial distribution of the quantified damage shows good correspondence to the estimated epicentres of the earthquakes of the sequence. The macroseismic effects of the earthquake sequence are described and compared to those of the South Iceland earthquakes in June 2000 and May 2008. It is argued that the magnitude estimate of the largest event of the sequence as obtained by Professor Ambraseys, based entirely on teleseismic measurements, is likely to be more accurate than other estimates based on the extent of the damaged area. This argument is supported by a discussion based on a comparison between the felt area, damaged area, and seismic moment estimates of the June 2000 earthquakes with the documented effects of the 1896 main shock. The observations and discussions presented here highlight the importance of Professor Ambraseys in the study of historic earthquakes.

A Reevaluation of the Intensities of the Northern Illinois Earthquake of 1909

The largest earthquake in northern Illinois is the m b ∼5.2 so‐called “Aurora” earthquake of 26 May 1909. Reports from nearly 500 newspapers yielded intensities for about 400 localities published in the days following the earthquake and indicate that many damage reports (especially in Bloomington, Kenosha, Platteville, and Aurora) were not as severe as previously interpreted. Some early wire reports of damage were exaggerated and later retracted, or were not supported by local newspapers. Conversely, some local accounts of extensive damage (e.g., at Morris, Illinois) were not widely reported by syndicated news media. The felt area extends further than that of previous studies—from the Ohio River to northern Wisconsin, and from Lansing, Michigan, to near Cedar Rapids, Iowa. The felt area centers near Sandwich, Illinois; the highest intensity, VII, is assigned to Morris, Illinois. The event was felt over an area of 350,000–400,000 km2 within a maximum radius of approximately 420 km. The distribution of felt area and intensity is similar to the m b 4.2 northern Illinois earthquake (28 June 2004), which has an instrumental epicenter near LaSalle, suggesting that the two events occurred in relatively close proximity. Our preferred epicenter for the 1909 event is near Sandwich, Illinois, based on intensity reports, and is located near the Sandwich fault, as is a potential small aftershock. This places the 1909 event into a tectonic framework and slightly further from the Chicago metropolitan area than previously proposed. Online Material: Tables of intensity reports, a list of newspapers from which intensity reports were extracted, and details of analog records and bulletins.