Improving the Representation of the Nocturnal Near-Neutral Surface Layer in the Urban Environment with a Mesoscale Atmospheric Model     

Syed Zahid Husain  Stéphane Bélair  Jocelyn Mailhot  Sylvie Leroyer 《Boundary-Layer Meteorology》2013,147(3):525-551

A new approach to improve the representation of surface processes in the Global Environmental Multiscale (GEM) atmospheric model associated with the exchanges between the urban canopy and the atmosphere is presented. Effects of the urban canopy on the evolution of surface-layer wind, temperature, moisture, and turbulence are directly parametrized in order to allow realistic interactions between the canopy elements (i.e., roofs, roads, and walls) and the atmosphere at GEM’s multiple vertical levels that are positioned inside the canopy. Surface energy budgets as implemented in the Town Energy Balance (TEB) scheme have been used to determine temperatures of the urban canopy elements for the proposed multilayer scheme. Performance of the multilayer scheme is compared against standard implementations of the TEB scheme for one nighttime intensive observation period of the Joint Urban 2003 experiment held in Oklahoma City, USA. Although the new approach is found to have a negligible impact on urban surface-layer wind profiles, it improves the prediction of near-neutral nocturnal profiles of potential temperature close to the surface. The urban heat island effect is simulated with a better accuracy by the multilayer approach. The horizontal temperature gradient across the central business district of the city along the direction of flow is also reasonably well captured by the proposed scheme.  相似文献   

Cenozoic denudation in the Marrakech High Atlas,Morocco: insight from apatite fission‐track thermochronology     

Yves Missenard  Omar Saddiqi  Jocelyn Barbarand  Pascale Leturmy  Geoffrey Ruiz  Fatima‐Zahra El Haimer  Dominique Frizon de Lamotte 《地学学报》2008,20(3):221-228

In North Africa, the High Atlas belt culminates at more than 4000 m. In Morocco, recent work shows that a lithospheric thinning explains about 1000 m of the mean topography, the remaining topography being related to crustal shortening. We combine regional geology with new apatite fission‐track (AFT) ages to constrain the timing of these events in the Marrakech High Atlas (MHA). In the inner belt, 10 AFT ages are comprised between 9 ± 1 and 27 ± 3 Ma. These Neogene ages indicate that the MHA underwent significant denudation during that time. In the southern foreland domain of the belt, three samples give scattered AFT ages between 27 ± 2 and 87 ±5 Ma. Geological evidences allow us to constrain the age of a major denudation event during Middle Miocene age. We propose that it is linked to the thermal doming highlighted in the whole Moroccan Atlas domain.  相似文献   

Detailed mineralogy and petrology of manganese oxyhydroxide deposits of the Imini district (Morocco)     

A. Dekoninck  A. Bernard  J. Barbarand  B. Saint-Bezar  Y. Missenard  R. Lepretre  O. Saddiqi  J. Yans 《Mineralium Deposita》2016,51(1):13-23

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Ore and Alteration Types of the Gold and Copper Mineralization in the Lascogon Project, Surigao del Norte, Mindanao Island, Philippines     

Jonelle Nikolai Crisostomo    Jeddalyn Parian    Daizo Ishiyama    Redempta Baluda    Sonia Eguia    Jocelyn Galapon    Gerry Comia    Jessie Segura    Maureen Laroco    Noel Oliveros  Victor B. Maglambayan 《Resource Geology》2007,57(2):241-247

Two ore and three alteration types were identified in the Lascogon Project of Philex Gold Philippines, in Surigao del Norte, Mindanao Island, Philippines. The jasperoid ore is the host to the Carlin‐like gold mineralization in the Lascogon and Danao prospects. The ore occurs in a decalcified and silicified horizon, with minor chlorite and goethite, stibnite, pyrite and quartz crystals ranging from cryptocrystalline to botryoidal. The stringer–stockwork type Cu‐Au mineralization in the Suyoc prospect is hosted in argillized andesitic rocks of the Mabuhay Formation. The primary ore minerals are chalcopyrite with minor amounts of sphalerite. The alteration types identified are propylitic alteration, argillic alteration and silicification. The propylitized basaltic and andesitic flows of the Bacuag Formation bound the jasperoid mineralization in the Lascogon prospect. Stratigraphically, the relationship between propylitized basalts and stringer–stockwork Cu‐Au is not clear but a lateral change can be inferred from jasperoid in the center and stringer–stockwork towards the east.  相似文献   

Fiamme textures in volcanic successions: Flaming issues of definition and interpretation     

Katharine F. Bull  Jocelyn McPhie 《Journal of Volcanology and Geothermal Research》2007

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Accurate time–frequency–wavenumber analysis to study coda waves     

Estelle Schisselé  Jocelyn Guilbert  Stéphane Gaffet  Yves Cansi 《Geophysical Journal International》2004,158(2):577-591

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Sustainability,development and rural aboriginal communities     

Jocelyn Davies  Elspeth Young 《The Australian geographer》1995,26(2):150-155

Aborigines, because of their population numbers and increasing control over land and resources, are crucial to the sustainable development of rural Australia. However, appropriate Aboriginal development requires the replacement of the ‘top‐down’ approaches generally adopted by government agencies by ‘bottom‐up’ approaches reflecting the needs and aspirations of rural Aboriginal people. Past experience demonstrates that Aborigines have faced many frustrations in reconciling these concepts. But some approaches now being adopted in the use and management of Australia's rangelands provide interesting alternatives which may be more generally applicable in enhancing rangeland sustainability. Examples include land‐use practices conducted by Aborigines living in remote homeland centres on their own freehold land, and the diversity of land uses introduced on pastoral stations now under Aboriginal ownership. Broader recognition of the value of these approaches will depend on widespread acknowledgment of the overall worth of Aboriginal land management knowledge in rural restructuring  相似文献   

Laboratory scale study of an industrial phosphate and thermal treatment for polluted dredged sediments   总被引：1，自引：0，他引：1  

Souhila KRIBI  Jocelyn RAMAROSON  Ange NZIHOU  Patrick SHARROCK  Guy DEPELSENAIRE 《国际泥沙研究》2012,27(4):538-546

Dredged sediments are being chemically treated with phosphoric acid on an industrial scale.The effectiveness of the treatment was evaluated by performing the chemical reaction in a tubular reactor, followed by convective drying and maturation of the treated sediment at ambient temperature and finally thermal destruction of the organic matter by calcinations(500℃-900℃).The influence of acid concentration and calcination temperature on the specific surface area of the sediment was investigated. The stabilization of the heavy metals was evaluated by leaching tests and sequential extraction procedures.The phosphoric acid treatment is effective in reducing heavy metal mobility,a prerequisite for recycling the sediments in various construction materials.  相似文献   

Compositional characteristics and geodynamic significance of late Miocene volcanic rocks associated with the Chah Zard epithermal gold–silver deposit,southwest Yazd,Iran          下载免费PDF全文

Majid Ghaderi  Mohammad Hashem Emami  Sebastien Meffre  Vadim Kamenetsky  Jocelyn McPhie  Khin Zaw  Rasoul Nasiri Bezenjani 《Island Arc》2018,27(1)

Whole‐rock geochemical and Sr–Nd isotopic data are presented for late Miocene volcanic rocks associated with the Chah Zard epithermal Au–Ag deposit in the Urumieh‐Dokhtar Magmatic Arc (UDMA), Iran, to investigate the magma source, petrogenesis and the geodynamic evolution of the study area. The Chah Zard andesitic to rhyolitic volcanic rocks are characterized by significant Large Ion Lithophile Element (LILE) and Light Rare Earth Element (LREE) enrichment coupled with High Field Strength Element (HFSE) depletion. Our geochemical data indicate an adakitic‐like signature for the volcanic rocks (e.g. SiO₂ > 62 wt%, Al₂O₃ > 15 wt%, MgO < 1.5 wt%, Sr/Y > 70, La/Yb > 35, Yb < 1 ppm, and Y < 18 ppm, and no significant Eu anomalies), distinguishing them from the other volcanic rocks of the UDMA. The Chah Zard volcanic rocks have similar Sr and Nd isotopic compositions; the ⁸⁷Sr/⁸⁶Sr(i) ratios range from 0.704 902 to 0.705 093 and the ε_Nd(i) values are from +2.33 to +2.70. However, the rhyolite porphyry represents the final stage of magmatism in the area and has a relatively high ⁸⁷Sr/⁸⁶Sr ratio (0.705 811). Our data suggest that the andesitic magmas are from a heterogeneous source and likely to result from partial melting of a metasomatized mantle wedge associated with a mixture of subducted oceanic crust and sediment. These melts subsequently underwent fractional crystallization along with minor amounts of crustal assimilation. Our study is consistent with the model that the volcanic host rocks to epithermal gold mineralization in the UDMA are genetically related to late Miocene Neo‐Tethyan slab break‐off beneath Central Iran.  相似文献   

The 1995–96 decline of R Coronae Borealis: high-resolution optical spectroscopy     

N. Kameswara Rao  David L. Lambert  Mark T. Adams  David R. Doss  Guillermo Gonzalez  Artie P. Hatzes  C. Renée James  C. M. Johns-Krull  R. Earle Luck  Gajendra Pandey  Klaus Reinsch  Jocelyn Tomkin  Vincent M. Woolf 《Monthly notices of the Royal Astronomical Society》1999,310(3):717-744

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