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91.
On 3 December 1828 at half past six in the evening, the border region between Belgium and Germany was stricken by a moderate earthquake. Up to now, the available information on this event has been essentially provided by a few contemporaneous scientific studies. To better evaluate its impact, location and magnitude, we have searched for new original historical reports. We collected 57 additional witness testimonies, which complete those previously collected about the earthquake effects. Among the testimonies, we also retrieved a questionnaire sent by the Prussian government to local authorities with the purpose of quickly obtaining information on the earthquake effects in the western part of the kingdom of Prussia. This inquiry is the oldest of its kind that has been discovered to date in this part of Europe, suggesting a rare concern by a national authority about the seismic hazard, and prefiguring the seismic inquiries that scientific institutions use today. The analysis of these new data made it possible to evaluate the intensity in 50 cities out of the 75 where the earthquake was observed. From these intensity data, we determine that the epicentre was in the Hautes-Fagnes region [lat. 50.38°N/long. 6.19°E?±?30 km] where moderate damage, corresponding to EMS-98 intensity VI–VII, was observed. At large distances, the earthquake was felt as far as Düsseldorf to the north, Brussels to the west, Metz to the south and Wiesbaden to the east. These distances correspond to a perceptibility radius of about 150 km. The magnitude of this earthquake is evaluated to be ML?=?4.7 (?0.2/+0.5) and MW?=?4.2 (+0.4/?0.2).  相似文献   
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93.
Temporal and spatial information on land use/cover is a prerequisite for effective planning decisions in the context of social and economic development. Satellite remote sensing data have become increasingly important in the study of land use/cover changes. This paper uses multitemporal satellite data to measure and spatially characterize land use/cover changes in the Jaffna Peninsula, northern Sri Lanka over the two decades from 1984 to early 2004 in terms of potential drivers. Over this period, the Jaffna Peninsula has been impacted severely by armed conflict between the government of Sri Lanka and the Liberation Tigers of Tamil Eelam. A postclassification method is used to compare land use/cover classes from satellite images using Geographical Information Systems (GIS) to analyze the spatial pattern of land use/cover changes over the study period. Results indicate that the land use/cover pattern has been very dynamic since early the 1980s, showing a remarkable decrease in agricultural land use and concomitant increase in non-agricultural land uses. The ethnic conflict and its consequences, particularly large-scale population migrations, have been the main driving forces for such land use/cover changes in the Jaffna Peninsula. The results of this study are not only important in aiding efforts to reconstruct this area after decades of physical and socioeconomic devastation, but should also prompt similarly urgent studies in other inaccessible war-torn areas of the world.  相似文献   
94.
The present work investigates a mountain front within the Plio-Quaternary deposits belonging to the sedimentary fill of the Guadix-Baza Basin (Betic Cordillera, Southern Spain). This 30 km-long front, developed in soft sediments and within a context of high erosion, is generated by the recent activity of the Baza Normal Fault. The mountain front is the natural limit between the western and eastern sectors, corresponding to the two sub-basins of Guadix and Baza. The two main glacis described in previous works in the area of the Baza Fault – the Old Glacis in the Guadix Sub-basin and the Recent Glacis in the Baza Sub-basin – are interpreted here as a single one, displaced by the fault. Using this Glacis as a marker we deduced that its age and the transition of the basin from endorheic to exorheic must be much older than previous estimations. The Baza Fault may be considered as one of the most active faults of the central part of the Betic Cordillera, according to the results of the general quantitative analysis of the mountain front relief using the Smf/Vf ratio and the SL index.  相似文献   
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96.
A 12-year period experimental data, from 1 January 1995, to 20 August 2007, have been examined for possible correlations between Seismic Electric Signals (SES) of the VAN method and source parameters of the corresponding earthquakes in Western Greece. During that period 13 earthquakes of magnitude M W ≥ 5 with epicenters in the area 19–24°E, 36–41°N and available the CMT solutions (Centroid Moment Tensor focal mechanism solutions) have been found to be preceded by a SES each time at one of the three VAN stations of IOA, PIR or PAT. The results of IOA and PIR stations are compared to those reported by Uyeda et al. 1999, for the previous period 1983–1994. The IOA station seems to be sensitive to earthquakes with thrust type mechanisms being mainly consistent to its past behavior. The PIR station, which is moved from its previous position by few kilometers, exhibits some changes. It detects now both strike slip and thrust type earthquakes and becomes sensitive to new areas indicating probably the strong dependence of the SES station detection ability upon its location.  相似文献   
97.
Study of a longshore transect off Southern California suggests that the length scales (22 to 27 km) of phytoplankton species patches may be related to those of low-frequency currents. The patch boundaries were independent of shelf width but they were probably not independent of changes in chlorophyll fluorescence, temperature, and bottom topography.  相似文献   
98.
A sequence of 25 bread-kiln floors was sampled for archaeomagnetic measurements in a bakehouse in the old town of Lübeck, Germany. Due to archaeological dating this kiln floor sequence has been built up presumably from the late 13 th to the 18 th century. The primary magnetisation component is carried by magnetite (maghemite) and is very stable. Small viscous magnetisation components could be removed easily. The preliminary results of characteristic remanent magnetisation for 23 of the kiln-floor layers show clearly the trend of the geomagnetic secular variation expected for that time interval. By comparison with French and British master curves, the kiln-floor sequence started around 1425 and lasted until 1775 AD. Presently, confidence circles are relatively large and need refineing by measuring more samples, which have already been collected. Together with 14 C dating that can be determined from the charcoals found in the lowest layers and thermoluminescence dating of the layers, we expect to obtain, for the first time, a secular variation curve for Northern Germany covering the time interval from 1400 to 1800 years AD.  相似文献   
99.
Aquatic organisms are extensively exposed to phthalate esters. We have investigated in trout the effects of diethylhexylphthalate (DEHP) and dibutylphthalate (DBP) on xenobiotic metabolizing enzymes which have been suggested as possible environmental biomarkers. Rainbow trout (Oncorhynchus mykiss) were waterborne exposed to DEHP (1 mg/l) or DBP (0.1 or 1 mg/l) for 72 h. Another group of rainbow trout received daily for 3 days an intraperitoneal injection of 50 mg/kg of DEHP or DBP. Laurate hydroxylation, ethoxyresorufin-o-deethylation, UDP-glucuronyltransferase activity and glutathione-S-transferase activity were measured in liver and extrahepatic tissues. The phthalate esters have been found not to induce these enzymes; in particular, the results do not support the previously described induction of lauric acid hydroxylase in sea bass treated with DEHP [Comp. Biochem. Physiol. B122 (1999) 253.].  相似文献   
100.
There is increasing evidence that natural disasters can trigger technological accidents and damage. These so-called Natech accidents can pose a significant risk to regions that are unprepared for responding to them. The European Commission’s Joint Research Centre has recognised the risk associated with Natech events and has started systematic research into Natechs and their underlying dynamics. This work investigates the risk associated with the flooding of industrial installations through an analysis of past case histories and using expert judgement. The potential impact of three levels of flood severity on selected industrial facilities storing and/or processing (eco-)toxic, flammable or explosive materials is analysed qualitatively and a scale is developed that links the flood intensity to the level of potential damage. Our analysis indicates that natural disasters have the potential for triggering hazmat releases and other types of technological accidents. Hence, natural disasters should be considered as separate accident-triggering events in the planning, design and operating stages of industrial facilities that process or store hazardous substances. Our work revealed a lack of detailed information on the occurrence of Natech events which indicates not necessarily a scarcity of Natechs but rather a lack of standardised reporting and record keeping.  相似文献   
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