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951.
Houben Georg J. Wachenhausen Julia Guevara Morel Carlos R. 《Hydrogeology Journal》2018,26(4):1285-1294
Hydrogeology Journal - Well ageing is mostly caused by mechanical and biogeochemical clogging processes, which affect the gravel pack, screen slots and casing. Clogging deposits increase head... 相似文献
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Machaček Jan Staubach Patrick Tavera Carlos Eduardo Grandas Wichtmann Torsten Zachert Hauke 《Acta Geotechnica》2022,17(11):5253-5273
Acta Geotechnica - This paper presents an approach for the automatic parameter calibration (AC) of a hypoplastic constitutive soil model. The calibration software developed in this work simplifies... 相似文献
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Carlos Roberto Sanquetta Ana Paula Dalla Corte Allan Libanio Pelissari Margarida Tomé Greyce Charllyne Benedet Maas Mateus Niroh Inoue Sanquetta 《Carbon balance and management》2018,13(1):20
Background
We analyzed the dynamics of carbon (C) stocks and CO2 removals by Brazilian forest plantations over the period 1990–2016. Data on the extent of forests compiled from various sources were used in the calculations. Productivities were simulated using species-specific growth and yield simulators for the main trees species planted in the country. Biomass expansion factors, root-to-shoot ratios, wood densities, and carbon fractions compiled from literature were applied. C stocks in necromass (deadwood and litter) and harvested wood products (HWP) were also included in the calculations.Results
Plantation forests stocked 231 Mt C in 1990 increasing to 612 Mt C in 2016 due to an increase in plantation area and higher productivity of the stands during the 26-year period. Eucalyptus contributed 58% of the C stock in 1990 and 71% in 2016 due to a remarkable increase in plantation area and productivity. Pinus reduced its proportion of the carbon storage due to its low growth in area, while the other species shared less than 6% of the C stocks during the period of study. Aboveground biomass, belowground biomass and necromass shared 71, 12, and 5% of the total C stocked in plantations in 2016, respectively. HWP stocked 76 Mt C in the period, which represents 12% of the total C stocked. Carbon dioxide removals by Brazilian forest plantations during the 26-year period totaled 1669 Gt CO2-e.Conclusions
The carbon dioxide removed by Brazilian forest plantations over the 26 years represent almost the totality of the country´s emissions from the waste sector within the same period, or from the agriculture, forestry and other land use sector in 2016. We concluded that forest plantations play an important role in mitigating GHG (greenhouse gases) emissions in Brazil. This study is helpful to improve national reporting on plantation forests and their GHG sequestration potential, and to achieve Brazil’s Nationally Determined Contribution and the Paris Agreement.954.
Silva Vitor Taherian Amir Oliveira Carlos Sousa 《Bulletin of Earthquake Engineering》2022,20(11):5545-5565
Bulletin of Earthquake Engineering - In the last five centuries, Portugal was affected by several earthquakes of strong magnitude (M > 7) that caused widespread destruction and a... 相似文献
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Foko Tamba Carlos Kengni Lucas Tematio Paul Manefouet Bertile Ilalie Kenfack Jean Victor 《Geotechnical and Geological Engineering》2022,40(8):4195-4215
Geotechnical and Geological Engineering - Early surface and structural deterioration of new pavements are becoming increasingly perceptible in Cameroon. This raises serious concerns regarding the... 相似文献
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Anisotropic P-wave attenuation measured from a multi-azimuth surface seismic reflection survey 总被引:2,自引:0,他引:2
Roger A. Clark Philip M. Benson rew J. Carter Carlos A. Guerrero Moreno 《Geophysical Prospecting》2009,57(5):835-845
A system of aligned vertical fractures produces azimuthal variations in stacking velocity and amplitude variation with offset, characteristics often reported in seismic reflection data for hydrocarbon exploration. Studies of associated attenuation anisotropy have been mostly theoretical, laboratory or vertical seismic profiling based. We used an 11 common‐midpoint‐long portion of each of four marine surface‐seismic reflection profiles, intersecting each other at 45° within circa 100 m of a common location, to measure the azimuthal variation of effective attenuation, Q−1eff and stacking velocity, in a shallow interval, about 100 m thick, in which consistently orientated vertical fracturing was expected due to an underlying salt diapirism. We found qualitative and quantitative consistency between the azimuthal variation in the attenuation and stacking velocity, and published amplitude variation with offset results. The 135° azimuth line showed the least apparent attenuation (1000 Q−1eff= 16 ± 7) and the fastest stacking velocity, hence we infer it to be closest to the fracture trend: the orthogonal 45° line showed the most apparent attenuation (1000Q−1eff= 52 ± 15) and slowest stacking velocity. The variation of Q−1eff with azimuth φ is well fitted by 1000Q−1eff = 34 − 18cos[2(φ+40°)] giving a fracture direction of 140 ± 23° (±1SD, derived from ‘bootstrapping’ fits to all 114 combinations of individual common‐midpoint/azimuth measurements), compared to 134 ± 47° from published amplitude variation with offset data. The effects of short‐window spectral estimation and choices of spectral ratio bandwidth and offset ranges used in attenuation analysis, individually give uncertainties of up to ±13° in fracture direction. This magnitude of azimuthal variation can be produced by credible crack geometries (e.g., dry cracks, radius 6.5 m, aspect ratio 3 × 10−5, crack density 0.2) but we do not claim these to be the actual properties of the interval studied, because of the lack of well control (and its consequences for the choice of theoretical model and host rock physical properties) and the small number of azimuths available here. 相似文献
959.
This paper briefly reviews the main topics developed in the last 15 years dealing with advances on predicting earthquake scenarios for the Lisbon Region. These developments, which have been reverted into seismic scenario simulators, include the entire earthquake process, as different modules, from the seismic source to vulnerability modelling. Recent achievements in several modules are presented, describing the level of uncertainties associated with the source, attenuation, soil effect, typology classification and inventory of the building stock, and vulnerability assessment of each typology. One simplified model is shown, and results of other models are compared for two selected occurrence scenarios. The paper ends with a brief appointment on the selection of scenario types, a key point in the application of simulators, and highlights the issues where more research and development should be made to optimize the gains in knowledge and to reduce overall uncertainties. 相似文献
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