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The assessment of net rainfall, defined as the intermediate hydrological variable linked in between the hillslope and the river network, is a challenge. This paper presents a method for net rainfall estimation, using inverse modelling associated to a geomorphology-based transfer function. The analysis is carried out in semi-arid Tunisia, with a dataset from event discharges in a mesoscale dryland basin. A complete sensitivity analysis is developed, along with a discussion of validity limits for simplifying assumptions and the identification of paths for improvement. This work could be relevant for data-scarce areas, thanks to the use of simple dynamic conceptualization and being based on observable geomorphological features, adjusted to the available data and knowledge. 相似文献
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Eric?HellebrandEmail author Jonathan?E.?Snow Smail?Mostefaoui Peter?Hoppe 《Contributions to Mineralogy and Petrology》2005,150(5):486-504
Clinopyroxenes (cpx) in abyssal and ophiolitic peridotites are commonly analyzed for lithophile trace element abundances in
order to estimate degrees of melting and porosity conditions during melt extraction, assuming that these data reflect near-solidus
conditions. During cooling, however, cpxs always exsolve into parallel lamellae of low-Ca enstatite and high-Ca diopside.
This may potentially lead to redistribution of the initial trace element budget. Since orthopyroxene (opx) cannot significantly
host most incompatible trace elements, exsolution will lead to an enrichment in the cpx lamellae. In order to address a possibly
exsolution-controlled partitioning between cpx and opx, we have obtained major and trace element mineral compositions on 14
plagioclase-free ocean floor mantle rocks. They cover the entire abyssal peridotite compositional spectrum from very fertile
to highly depleted compositions. The mean volume proportion of opx lamellae in cpx porphyroclasts lies around 15% of the original
cpx. For the light to middle rare earth elements, the enrichment in the measured cpx exsolution is exclusively controlled
by these phase proportions. Relative to these highly incompatible trace elements, solely Ti and Yb partition significantly
into opx. Lamellar interpyroxene partition coefficients, estimated from NanoSIMS analyses, are around three times as high
as the ones for near-solidus bulk pyroxene. The equilibration temperatures for the exsolution lamella are slightly higher
than 800°C. The bulk cpx can be reconstructed using the lamellar proportions and their relative partitioning. The implication
of such a reconstruction is that the cpx rare earth element patterns shift almost in parallel to lower values. These shifts,
however, do not affect mantle melting models proposed thus far for mid-ocean ridges.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
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R. J. Ivison Ian Smail A. J. Barger J.-P. Kneib A. W. Blain F. N. Owen T. H. Kerr L. L. Cowie 《Monthly notices of the Royal Astronomical Society》2000,315(2):209-222
We present extensive observations of a sample of distant, submillimetre (submm) galaxies detected in the field of the massive cluster lens Abell 1835, using the Submm Common-User Bolometer Array (SCUBA). Taken in conjunction with earlier observations of other submm-selected sources, we now have detailed, multiwavelength observations of seven examples of the submm population, having exploited the combination of achromatic amplification by cluster lenses and lavish archival data sets. These sources, all clearly at z ≳1, illustrate the wide range in the radio and optical properties of distant submm-selected galaxies. We include detailed observations of the first candidate 'pure' starburst submm galaxy at high redshift, a z =2.56 interacting galaxy which shows no obvious sign of hosting an AGN. The remaining sources have varying degrees of inferred AGN activity (three out of seven of the most luminous show some evidence of the presence of an AGN), although even when an AGN is obviously present it is still not apparent whether reprocessed radiation from this source dominates the submm emission. In contrast with the variation in the spectral properties, we see relatively homogeneous morphologies for the population, with a large fraction of merging or interacting systems. Our study shows that virtually identical spectral energy distributions are seen for galaxies that exhibit strikingly different optical/UV spectral-line characteristics. We conclude that standard optical/UV spectral classifications are misleading when applied to distant, highly obscured galaxies, and that we must seek other means of determining the various contributions to the overall energy budget of submm galaxies and hence to the far-infrared extragalactic background. 相似文献
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R. J. Ivison T. R. Greve J. S. Dunlop J. A. Peacock E. Egami Ian Smail E. Ibar E. van Kampen I. Aretxaga T. Babbedge A. D. Biggs A. W. Blain S. C. Chapman D. L. Clements K. Coppin D. Farrah M. Halpern D. H. Hughes M. J. Jarvis T. Jenness J. R. Jones A. M. J. Mortier S. Oliver C. Papovich P. G. Pérez-González A. Pope S. Rawlings G. H. Rieke M. Rowan-Robinson R. S. Savage D. Scott M. Seigar S. Serjeant C. Simpson J. A. Stevens M. Vaccari J. Wagg C. J. Willott 《Monthly notices of the Royal Astronomical Society》2007,380(1):199-228
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Ian Smail 《Astrophysics and Space Science》2002,281(1-2):453-456
I present a brief summary of the results from extensive multi-wavelength observations of the submillimetre-selected galaxies.
I discuss the properties of this population, in particular their interpretation within the framework of our understanding
of galaxy formation and evolution.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献