从2014年4月1日智利地震认识前震     

Emily E Brodsky  Thorne Lay 《国际地震动态》2015,(7)

<正>最近一些大地震如2014年4月1日智利地震之前的地震活动分析结果揭示,一些大地震是有可能被预测的。大地震之前是否有可测量的、明显的前兆异常来警示我们?一直以来,前震被认为是地震预测最有希望的指标。至少一半以上的大地震有前震,但这些前震很难从非前兆地震活动中区分出来。2014年4月1日智利地震及近期其他大地震的前震活动表明,大地震前可能存在可观测的前兆异常。地震相互作用的统计模型表明,当区域  相似文献   

Closed Circuit Television (CCTV) Earthquake Behaviour Coding Methodology: analysis of Christchurch Public Hospital video data from the 22 February Christchurch earthquake event     

Emily S. Lambie  Thomas M. Wilson  Erik Brogt  David M. Johnston  Michael Ardagh  Joanne Deely  Steven Jensen  Shirley Feldmann-Jensen 《Natural Hazards》2017,86(3):1175-1192

Earthquake epidemiological research indicates that the behavioural response influences the nature and severity of injuries sustained. However, there is no observational evidence of the actions individuals engage in during and immediately following earthquake shaking, and the context in which earthquake injuries and deaths are caused. Closed Circuit Television Earthquake Behaviour Coding Methodology has been developed as a tool to classify human behaviour during and immediately following earthquake shaking using real event video data. The coding methodology was applied to security video data captured during the 22 February 2011 M_w6.3 ‘Christchurch’ earthquake event from the Christchurch Public Hospital which experienced shaking intensity of MM9 lasting approximately 12–15 s. We applied this coding methodology to determine: demography, trans-event behavioural responses, post-event behavioural responses, influence of social context on behaviour, and influence of behaviour on injuries. A total of 213 individuals from 31 different camera views were analysed. Sixty-six per cent of the individuals were adult-aged females. The primary trans-event responses were to hold (26%) onto furniture, walls, and/or other people close to them and to look around (30%). No individuals were observed to perform all ‘Drop, Cover, Hold’ actions, the recommended action during strong earthquake shaking in New Zealand. Post-event behaviour included: running, walking, providing assistance, moving towards others, visual communication, and some individuals gave instructions. Social contextual behaviour varied depending on the role of the adult. There were no serious injuries linked to behaviour. The results of this initial study indicate the coding methodology can record the distribution of and variation in human behaviours. Therefore, objective observation of earthquake video data can provide a useful quantitative measure of human behaviour. Significantly, the process will enable researchers to look more closely at behaviours, as well as the social and physical contexts associated with injury risk during and immediately following earthquake shaking.  相似文献   

震后快速钻探:历史、现状与未来     

Emily E.Brodsky  Kuo-Fong Ma  Jim Mori  Demian M.Saffer  李丽 《国际地震动态》2010,(4):9-18

大地震发生后立即在断层带上进行钻探可以帮助我们获取更多的地震信息,尤其是可获得决定断层动态破裂的摩擦水平和强度,观测断层的愈合过程及可能触发余震的应力变化,并可获取控制破裂过程的重要的物理和化学属性。在2008年11月由国际大陆科学钻探项目（ICDP）和南加州地震中心（SCEC）联合在日本东京举办的为期3天的“震后快速钻探：历史、现状与未来”研讨会上,  相似文献   

Analytical study on vulnerability functions for casualty estimation in the collapse of adobe buildings induced by earthquake     

Aiko Furukawa  Robin Spence  Yutaka Ohta  Emily So 《Bulletin of Earthquake Engineering》2010,8(2):451-479

Collapse of adobe buildings during an earthquakes with various earthquake intensities is analyzed using the 3-dimensional distinct element method code developed by the first author. Firstly, we evaluate structural damage with damage index, interior-space damage with w score, and human casualties in the collapsing buildings with three casualty criteria. Secondly, we investigate relationships between the earthquake intensity, the structural damage, the interior-space damage, and the casualties. It is found that the casualties have stronger correlation with the interior-space damage than the structural damage, and three vulnerability functions, namely, structural, interior-space and casualty vulnerability functions, are proposed. Effects of reinforcing methods on these functions are also examined. Finally, a series of analytical procedures to develop vulnerability functions and to estimate casualties using the functions are described.  相似文献   

Temporal and Spatial Dynamics of Diel-Cycling Hypoxia in Estuarine Tributaries     

Robin M. Tyler  Damian C. Brady  Timothy E. Targett 《Estuaries and Coasts》2009,32(1):123-145

The distribution and intensity of hypoxia (low dissolved oxygen) in estuaries is increasing worldwide due to cultural eutrophication. This study quantifies the strength of associations between the duration of diel-cycling severe hypoxia (≤2 mg O₂ l⁻¹) in bottom water (∼15 cm above bottom) of a shallow (<2 m) coastal lagoon estuary (Delaware, USA) and abiotic environmental variables (water temperature, insolation, tide, streamflow, and wind) and predicts the duration of severe hypoxia given different combinations of these variables. The intensity and spatial extent and dynamics of diel-cycling severe hypoxia events were defined. Vertical variability in dissolved oxygen (DO) concentration during the daytime was also determined. During the summers of 2001–2005, bottom DO data were collected for periods of weeks to months at multiple sites using automated sondes. Multiple linear regression (MLR) and regression tree analysis (RTA) were used to determine the relative importance of the environmental variables in predicting the number of hours of severe hypoxia per day. Key findings of the study were that severe hypoxia events of minutes to hours in duration occurred frequently in all four tributaries sampled, primarily between 0200 and 1000 hours. Severe hypoxia duration and diel-cycling amplitudes of DO concentration increased in the up-tributary direction. Hierarchically, the duration of severe hypoxia was influenced mostly by the mean daily water temperature, then by preceding days’ total insolation, percentage of morning hours (02:00 to 10:00 a.m.) ebb tide, and daily streamflow. Collectively, the variables examined by the MLR and the RTA approaches accounted for 62% and 65% of the variability in the duration of severe hypoxia, respectively. RTA demonstrated that daily mean water temperature above 26.3°C and previous day’s total insolation below 13.6 kW m⁻² were associated with the longest lasting severe hypoxic events (9.56 h). The environmental variables and combinations of conditions that modulate or augment diel-cycling hypoxia presented in this paper enhance understanding of this widespread and growing phenomenon and provide additional insight regarding the extent to which it can impact food webs in very shallow estuarine waters that often serve as nursery habitat.  相似文献   

Conodont biostratigraphy across the Permian–Triassic boundary at the Dawen section, Great Bank of Guizhou, Guizhou Province, South China: Implications for the Late Permian extinction and correlation with Meishan     

Jun Chen  Tyler W. Beatty  Charles M. Henderson  Harry Rowe   《Journal of Asian Earth Sciences》2009,36(6):442

Several continuous Permian–Triassic boundary (PTB) sections are well exposed in the interior of the Great Bank of Guizhou (GBG) on the east limb of the Bianyang syncline, Luodian County, Guizhou Province, South China. Fourteen conodont taxa are identified, including Clarkina kazi, Clarkina lehrmanni n. sp., Clarkina taylorae, Clarkina zhejiangensis, Hindeodus eurypyge, Hindeodus inflatus, Hindeodus sxlatidentatus, Hindeodus parvus erectus, Hindeodus parvus parvus, Hindeodus postparvus, Hindeodus praeparvus, Hindeodus typicalis, Isarcicella staeschei, and Merrillina ultima based on a detailed study of the Permian-Triassic interval at the Dawen section. The first occurrence (FO) of H. parvus parvus in the lower Daye Formation, at about 7.45 m above the contact surface between the Upper Permian skeletal packstone and a calcimicrobial framestone unit, is correlated with the Permian–Triassic boundary; the occurrence of H. eurypyge, H. praeparvus and M. ultima immediately below and H. postparvus above the interval supports this interpretation. A morphometric analysis of 31 Hindeodus specimens helped distinguish H. parvus erectus from H. parvus parvus and H. postparvus. Correlation with the Meishan section (PTB GSSP) using both conodont biostratigraphy and carbon isotopes, indicates that the major extinction at the two localities is simultaneous and coincides with the top of the skeletal packstone at Dawen. The contact between the skeletal packstone and the calcimicrobialite is very irregular and has previously been interpreted as a dissolution surface and correlated with a surface in the lower part of bed 27 at Meishan. Our results confirm this interpretation and reveal that the dissolution event postdated the extinction.  相似文献   

A Review of: “From Urban Enclave to Ethnic Suburb: New Asian Communities in Pacific Rim Countries”     

Emily Skop 《The Professional geographer》2013,65(1):152-154

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Organic micropollutants in marine plastics debris from the open ocean and remote and urban beaches   总被引：2，自引：0，他引：2  

Hirai H  Takada H  Ogata Y  Yamashita R  Mizukawa K  Saha M  Kwan C  Moore C  Gray H  Laursen D  Zettler ER  Farrington JW  Reddy CM  Peacock EE  Ward MW 《Marine pollution bulletin》2011,62(8):1683-1692

To understand the spatial variation in concentrations and compositions of organic micropollutants in marine plastic debris and their sources, we analyzed plastic fragments (∼10 mm) from the open ocean and from remote and urban beaches. Polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), dichloro-diphenyl-trichloroethane and its metabolites (DDTs), polybrominated diphenyl ethers (PBDEs), alkylphenols and bisphenol A were detected in the fragments at concentrations from 1 to 10,000 ng/g. Concentrations showed large piece-to-piece variability. Hydrophobic organic compounds such as PCBs and PAHs were sorbed from seawater to the plastic fragments. PCBs are most probably derived from legacy pollution. PAHs showed a petrogenic signature, suggesting the sorption of PAHs from oil slicks. Nonylphenol, bisphenol A, and PBDEs came mainly from additives and were detected at high concentrations in some fragments both from remote and urban beaches and the open ocean.  相似文献   

Unexpected post-settlement freshening and increase in charophytes in Bombah Broadwater (Myall Lakes,New South Wales,Australia)     

Emily?LeydenEmail author  John?Tibby  Adriana?García  Atun?Zawadzki 《Journal of Paleolimnology》2011,46(4):637-647

Bombah Broadwater is a shallow coastal lake within the Ramsar-listed Myall Lakes system on the mid-north coast of New South Wales, Australia. Increased nutrient and sediment loads resulting from catchment modification are thought to have instigated the loss of aquatic plants in the lake, causing it to “switch” from a clear, macrophyte dominated system (similar to the conditions in present day Myall Lake) to a turbid, phytoplankton dominated system. To assess this hypothesis, charophytes, foraminifera and aquatic fauna remains from an 800 year sediment record were examined. The sediment chronology was established using ¹⁴C, ²¹⁰Pb and ¹³⁷Cs radiometric dating and sediment composition. Interestingly, a clear increase in charophytes since European arrival conflicted with the hypothesised aquatic plant loss. Hence, it appears Bombah Broadwater has not undergone a change in stable state since European arrival. An additional and unexpected finding in the patterns of the foraminifera and testate amoeba suggest that Bombah Broadwater has freshened substantially since European arrival. This freshening may have resulted from increased catchment run off as a result of the clearance of catchment vegetation. Since catchment vegetation clearance is widespread in Australia, this finding raises the possibility that post-settlement freshening of coastal lakes may be a common occurrence.  相似文献   

V. Bojňanský and A. Fargašová: Atlas of seeds and fruits of Central and East-European flora. The Carpathian Mountains region.     

Emily E. Coffey 《Journal of Paleolimnology》2009,42(2):299-300

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