Esse blog foi criado em 2007 para divulgar a ciência dos Terremotos. Divulgando quando necessários os tremores no Brasil e temas importantes sobre a sismologia!
Fonte: terraUm aposentado chinês criou um novo design de cama que, em caso de terremoto, automaticamente se transforma em uma espécie de bunker e protege quem estiver nela de sofrer suas consequências. Nesta quarta-feira, a invenção tornou-se uma patente nacional.
O objeto, composto por módulos, incluindo armários em cada ponta e uma placa móvel (com rolamentos) com capacidade para suportar cargas elevadas, pode ser usado normalmente para dormir e armazenar objetos. No caso de um terremoto, suas partes se combinam de maneira a formar um abrigo, envolvendo e protegendo seu usuário, explica o site do jornal China Daily.
Elementos para suprir as necessidades básicas para a sobrevivência humana, como água potável e comida enlatada e outros equipamentos, como um megafone e um martelo, podem ser guardados em seus armários, como prevenção. Eles podem ser úteis para ajudar as pessoas a sobreviver por vários dias, até serem resgatadas, diz Wang.
O aposentado de 66 anos conta que vivenciou os terremotos de Xingtai e Tangshan, o que garantiu conhecimentos sobre tais desastres naturais, frequentes em seu país.
Cerca de 70 mil pessoas morreram na região de Wenchuan, província de Sichuan, sudoeste da China, em maio de 2008, quando um terremoto com magnitude 8 atingiu a região. Já em abril deste ano, um terremoto de magnitude 6,9 deixou outros 2.700 mortos em Yushu, uma região no noroeste da província de Qinghai.
Desde que Wang se aposentou de seu trabalho em um instituto local de artes industriais, mostrou bastante interesse por invenções e criações, conta o site Daily Chilli. O designer acredita que sua cama "salva-vidas" é útil principalmente para prédios baixos, feitos em tijolo e concreto, e bangalôs chineses. Esta é sua sexta invenção patenteada, incluindo uma máscara de soldagem automática e um freio de emergência para veículos.
O aposentado deveria ter criado um sistema de rádio-amador para a cama, para ser possível chamar por socorro em caso do inevitável ocorrer, opina ainda o site Geeky-gadgets. A equipe da Geek também sentiu falta da existência de um banheiro, em caso de outros tipos de emergência.
O grande terremoto que provocou um tsunami responsável pela morte de 192 pessoas em Samoa, em setembro de 2009, não foi um, mas três.
WEST LAFAYETTE, Ind. -- A new theory developed at Purdue University may solve the mystery of why the New Madrid fault, which lies in the middle of the continent and not along a tectonic plate boundary, produces large earthquakes such as the ones that shook the eastern United States in 1811 and 1812.
The theory suggests that the energy necessary to produce the magnitude 7-7.5 earthquakes came from stored stress built up in the Earth's crust long ago. Rapid erosion from the Mississippi River at the end of the last ice age reduced forces that had kept the New Madrid fault from slipping and triggered the temblors.
Eric Calais, the Purdue professor of earth and atmospheric sciences who led the study, said the theory is the first to explain how a fault could have had large earthquakes in the recent past but today show no signs of accumulating the forces needed to produce another earthquake.
"We understand why earthquakes happen at the contact between tectonic plates, like in California, but it has always been a puzzle as to why earthquakes occur in the middle of the continent as well, and with no visible surface deformation," Calais said. "Our theory links an external climate-driven process, the melting of the ice sheet, and earthquakes."
Calais and others have analyzed the fault for more than 10 years using global position system measurements to capture movements of the Earth's surface that represent a buildup of energy and have traditionally been used to evaluate the potential for an earthquake. As the data was collected, it became evident that such motion was not occurring along the New Madrid fault.
Andrew Freed, co-author of the paper and an associate professor of earth and atmospheric sciences at Purdue, said with no discernable motions at the surface to explain how the requisite crustal stresses could have built up in this area, these stresses must be left over from past tectonic processes that are no longer active.
"The only way to reconcile the fact that this part of the continent is not deforming but is producing earthquakes is for the stresses to have built up long ago, " Freed said. "Old geologic processes, such as the opening of the Atlantic and the uplift of the Rocky Mountains, may have squeezed the Midwest. The resulting stress remained stored for millions of years until uplift associated with the Mississippi erosion event led to the unclamping of old faults lying beneath."
If this area of the North American continent is preloaded with the stress that can lead to earthquakes, it will be difficult to assess earthquake risk in the region.
The fault segments that ruptured are unlikely to have future earthquakes as there is no current means to reload them, but there remains a risk that other faults in the region could experience large earthquakes in the future, Calais said.
"Unfortunately, this stored stress is invisible to us, and the usual methods of measuring strain and deformation to evaluate a spot's potential for an earthquake may not apply to this region," Calais said. "Under these conditions, once an earthquake occurs on a given fault, it's done; but this also means that other faults in the region that appear quiet today may still be triggered."
Details of the team's work, which was supported by a grant from the U.S. Geological Survey, appear in a paper in the current issue of Nature.
For a period from 16,000 to 10,000 years ago as the ice sheet melted, it steadily rushed water down the Mississippi River. As the river flowed, it washed away sediments and removed weight pressing down on the Earth's crust. With this relatively rapid removal of weight, the crust rebounded and bulged slightly up from its previous position. This slight arching caused the top layers of the Earth's crust to be stretched and the bottom layers to be compacted, exerting forces on the preexisting faults sufficient to trigger the earthquakes that began more than 3,000 years ago in the New Madrid region, culminating with the 1811-1812 events, Calais said.
More data needs to be collected to see whether this mechanism applies to similar seismic zones in the world, he said.
Additional paper co-authors include Roy Van Arsdale of the University of Memphis and Seth Stein of Northwestern University.
Writer: Elizabeth K. Gardner, 765-494-2081, ekgardner@purdue.edu
| Magnitude | 5.6 |
|---|---|
| Date-Time |
|
| Localização | 35.225°N, 59.271°E |
| Profundidade | 26.1 km |
| Distancias | próximo a Torbat-e Heydariyeh, Iran 115 km SSE de Neyshabur, Iran |
A cifra não inclui a receita nas salas IMAX. Esta é a primeira produção chinesa em IMAX.
O filme arrecadou mais de 100 milhões de yuans nos três primeiros dias de exibição, quebrando o recorde que anteriormente pertencia ao filme "A Fundação da República".
"Abalo Secundário" bateu o recorde bilheteria no seu primeiro dia de exibição, quando arrecadou 36,2 milhões de yuans, o melhor registro da bilheteria chinesa na estreia de uma produção nacional.
O diretor do filme, Feng Xiaogang, um dos diretores comerciais de maior sucesso na China, disse hoje em uma entrevista à Shinchua que a bilheteria do filme está perto do que ele esperava e que não haverá problema em arrecadar de 350 a 400 milhões durante as primeiras duas semanas.
"Abalo Secundário" conta a história de uma mãe que passa 30 anos procurando a filha desaparecida no terremoto.
O terremoto de Tangshan matou mais de 240 mil pessoas.
fonte:fri online
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This page is URL: http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/SAML_24hr.html
fonte:br.whatsnewÉ um mashup que mostra uma linha de tempo onde podemos navegar para ver os dados das diferentes atividades sísmicas.
Para utilizar Earthquake Timeline, indicamos a data, hora, cidade, etc., permitindo filtrar os resultados acompanhados por um pequeno mapa para localizar tudo geográficamente."
An earthquake results from sudden slip on a geological fault. [HN10] Such fracture and failure [HN11-13] problems are notoriously intractable. The heterogeneous state of the Earth and the inaccessibility of the fault zone to direct measurement impose further difficulties. Except during a brief period in the 1970s (2), the leading seismological authorities of each era have generally concluded that earthquake prediction is not feasible (3). Richter [HN14-15], developer of the eponymous magnitude scale, commented as follows in 1977: "Journalists and the general public rush to any suggestion of earthquake prediction like hogs toward a full trough... [Prediction] provides a happy hunting ground for amateurs, cranks, and outright publicity-seeking fakers" (4). This comment still holds true.
For large earthquakes to be predictable, they would have to be unusual events resulting from specific physical states. However, the consensus of a recent meeting [HN5] (5) was that the Earth is in a state of self-organized criticality [HN16] where any small earthquake has some probability of cascading into a large event. This view is supported by the observation that the distribution of earthquake size (see figure) is invariant [HN17] with respect to scale for all but the largest earthquakes. Such scale invariance is ubiquitous in self-organized critical systems (6). Whether any particular small earthquake grows into a large earthquake depends on a myriad of fine details of physical conditions throughout a large volume, not just in the immediate vicinity of the fault (7). This highly sensitive nonlinear dependence of earthquake rupture on unknown initial conditions severely limits predictability (8,9). The prediction of individual large earthquakes would require the unlikely capability of knowing all of these details with great accuracy. Furthermore, no quantitative theory for analyzing these data to issue predictions exists at present. Thus, the consensus of the meeting was that individual earthquakes are probably inherently unpredictable.
Critical quakes. Number of earthquakes from 1 January 1977 to 30 June 1996 in the Harvard catalog [HN27] (24) with magnitude greater thanM for shallow (0 to 70 km), intermediate (71 to 300 km), and deep (301 to 700 km) earthquakes. Dotted lines are power-law curves modified by an exponential taper for the largest magnitudes [equation 3 of (8)]. Analyses of smaller earthquakes show that self-similarity extends to magnitudes as small as zero (25). Such power-law curves are characteristic of systems in a state of self-organized criticality.Empirical earthquake prediction would require the existence of observable and identifiable precursors [HN18] that would allow alarms to be issued with high reliability and accuracy. There are strong reasons to doubt that such precursors exist (10). Thousands of observations of allegedly anomalous phenomena (seismological, geodetic, hydrological, geochemical, electromagnetic, animal behavior, and so forth) have been claimed as earthquake precursors, but in general, the phenomena were claimed as precursors only after the earthquakes occurred. The pattern of alleged precursors tends to vary greatly from one earthquake to the next, and the alleged anomalies are frequently observed at only one point, rather than throughout the epicentral region. There are no objective definitions of "anomalies," no quantitative physical mechanism links the alleged precursors to earthquakes, statistical evidence for a correlation is lacking, and natural or artificial causes unrelated to earthquakes have not been compellingly excluded (11). In other fields threshold signals have often been erroneously claimed as important physical effects (12); most if not all "precursors" are probably misinterpreted as well. Unfortunately, each new claim brings a new set of proposed conditions, so that hypothesis testing, which is what separates speculation from science, is nearly impossible.
Chinese seismologists claimed that the 4 February 1975 Haicheng (magnitude = 7.3) earthquake was successfully predicted and that "very few people were killed" (13). However, an official publication in 1988 (14) states there were 1328 deaths and 16,980 injured. This disparity casts doubt on claims [HN19] for the Haicheng prediction. China's Cultural Revolution was still taking place in 1975. An American delegation's report (15) captures the remarkable atmosphere: "Earthquake prediction was not a minor experiment.... Indeed, belief in earthquake prediction was made an element of ideological orthodoxy that distinguished the true party liners from right wing deviationists." The possibility that political pressures caused inaccuracies in claims for the Haicheng prediction cannot be excluded. An intense swarm of microearthquakes, many of which were large enough to be felt by local residents, began over 24 hours before the main shock (15). These microearthquakes might well have induced some spontaneous evacuation. At least 240,000 people died in the 1976 Tangshan, China, earthquake, which was not predicted.
Varotsos [HN20] and co-workers claim to be able to predict earthquakes in Greece on the basis of geoelectrical observations (16), but our analyses show their claims to be without merit (17,18). Some of the geoelectrical signals are artifacts of industrial origin (19), and there is no compelling evidence linking any of the geoelectrical signals to earthquakes. Controversy lingers primarily because Varotsos's claims have not been stated as unambiguous and objectively testable hypotheses (20).
Is prediction inherently impossible or just fiendishly difficult? In practice, it doesn't matter. Scientifically, the question can be addressed using a Bayesian approach [HN21] (21). Each failed attempt at prediction lowers the a priori probability for the next attempt. The current probability of successful prediction is extremely low, as the obvious ideas have been tried and rejected for over 100 years (17). Systematically observing subtle phenomena, formulating hypotheses, and testing them thoroughly against future earthquakes would require immense effort over many decades, with no guarantee of success. It thus seems unwise to invest heavily in monitoring possible precursors.
Seismology can, however, contribute to earthquake hazard mitigation. [HN22-25] Statistical estimates of the seismicity expected in a general region on a time scale of 30 to 100 years (22) [as opposed to "long-term predictions" of specific earthquakes on particular faults within a few years (23)] and statistical estimates of the expected strong ground motion are important data for designing earthquake-resistant structures. Rapid determination of source parameters (such as location and magnitude) can facilitate relief efforts after large earthquakes. Warnings of tsunamis [HN26] (seismic sea waves) produced by earthquakes also contribute significantly to public safety. These are areas where earthquake research can greatly benefit the public.
See referencer and more details in science - http://www.sciencemag.org/cgi/content/full/275/5306/1616
