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191.
The added value of the joint pre-stack inversion of PP (incident P-wave and reflected P-wave) and PS (incident P-wave and reflected S-wave) seismic data for the time-lapse application is shown. We focus on the application of this technique to the time-lapse (four-dimensional) multicomponent Jubarte field permanent reservoir monitoring seismic data. The joint inversion results are less sensitive to noise in the input data and show a better match with the rock physics models calibrated for the field. Further, joint inversion improves S-impedance estimates and provides a more robust quantitative interpretation, allowing enhanced differentiation between pore pressure and fluid saturation changes, which will be extremely useful for reservoir management. Small changes in reservoir properties are expected in the short time between the time-lapse seismic acquisitions used in the Jubarte project (only 1 year apart). The attempt to recover subtle fourth-dimensional effects via elastic inversion is recurrent in reservoir characterization projects, either due to the small sensitivity of the reservoirs to fluid and pressure changes or the short interval between the acquisitions. Therefore, looking for methodologies that minimize the uncertainty of fourth-dimensional inversion outputs is of fundamental importance. Here, we also show the differences between PP only and joint PP–PS inversion workflows and parameterizations that can be applied in other projects. We show the impact of using multicomponent data as input for elastic seismic inversions in the analysis of the time-lapse differences of the elastic properties. The larger investment in the acquisition and processing of multicomponent seismic data is shown to be justified by the improved results from the fourth-dimensional joint inversion.  相似文献   
192.
Doklady Earth Sciences - This research dealt with the topic of modeling the soil lost in a semi-arid desert area in the Ma’an watershed and its surroundings in Ma’an Governorate using...  相似文献   
193.
Acta Geotechnica - This article presents an experimental program under the constant volume condition to investigate the influence of over-consolidation on flow instability of clean and silty sand...  相似文献   
194.
Li  Zhenya  Ali  Zulfiqar  Cui  Tong  Qamar  Sadia  Ismail  Muhammad  Nazeer  Amna  Faisal  Muhammad 《Natural Hazards》2022,111(1):547-566
Natural Hazards - The increase of frequency and severity of extreme weather events due to climate change gives evidence of severe challenges faced by infrastructure systems. Among them, the...  相似文献   
195.
Natural Hazards - Landslides can cause extensive damage, particularly those triggered by earthquakes. The current study used back propagation of an artificial neural network (ANN) to conduct risk...  相似文献   
196.
Onuşluel Gül  Gülay  Gül  Ali  Najar  Mohamed 《Natural Hazards》2022,110(2):1389-1404

In the context of major outcomes of a steadily changing climate, extreme climatic conditions and the associated events in various forms of weather-related natural disasters, e.g. droughts, floods, and heat waves, are more frequently experienced on the global scale in recent years. In support of this argument, there are adequate numbers of explicit signals over such a persistent outlook, which is greatly illustrated by historical data and observations. This study, which is mainly oriented to investigating the drought behaviour in Thracian, Aegean and Mediterranean transects of Turkey's major river basins, is actually inspired by the foreseen potential of using annual maximum drought severity series (based on drought definition through the standardized precipitation index (SPI)) within a framework that resembles the use of flood discharge directly from flow measurements in a river basin. To this end, a series of spatial analyses were employed to identify different aspects of flood appearance in the study extent, including trend views on annual average drought severity series, shifts in the starting time of the annually most severe flood periods, and changes in spatial coverage views of average drought conditions under different drought severity categories. The framework of the analytical approaches depends greatly on validated international datasets and open-source computational algorithms. The results from the analyses that were conducted in two consecutive periods of 1958–1980 and 1981–2004 revealed that Turkey's western and southern river basin systems seemed to have experienced quite different behaviours between the two periods in terms of drought severity magnitudes, drought durations and annual occurrence times.

  相似文献   
197.
Pham  Quoc Bao  Ali  Sk Ajim  Bielecka  Elzbieta  Calka  Beata  Orych  Agata  Parvin  Farhana  Łupikasza  Ewa 《Natural Hazards》2022,113(2):1043-1081
Natural Hazards - Advances in the availability of multi-sensor, remote sensing-derived datasets, and machine learning algorithms can now provide an unprecedented possibility to predict flood events...  相似文献   
198.
Geotechnical and Geological Engineering - Rock abrasivity index (RAI) and uniaxial compressive strength (UCS) are two key parameters for assessing abrasivity and durability of building stones,...  相似文献   
199.
Omar  Kh.  Chorozoglou  D.  Mohamed  E. K.  El Rayess  M. 《Geotectonics》2022,56(2):257-263
Geotectonics - The monitoring of network measures, such as degree centrality, betweenness centrality, and clustering coefficient is performed, aiming to identify the periods that the earthquake...  相似文献   
200.
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