Trace Element Analysis of Geochemical Reference Samples by Energy Dispersive X-ray Fluorescence Spectrometry     

P.C. WEBB  P.J. POTTS  J.S. WATSON 《Geostandards and Geoanalytical Research》1990,14(3):361-372

A critical evaluation of trace element data derived by energy dispersive X-ray fluorescence (ED-XRF) analysis of over 40 geochemic reference samples shows that results for Rb, Sr, Y, Zr, Nb, and Th can be at least as good in terms of precision (better than ± 2 ppm (2s) or ± 3 % (2s relative), accuracy, and 3s detection limits (2 to 4 ppm) as those obtainable by other routine multi-element analytical techniques. Data obtained simultaneously for Ni, Cu, Zn, Ga, Pb and U are less precise because excitation conditions are less well optimised (with 3s detection limits of 6 to 12 ppm). The quality of data and the efficiency of simultaneous analysis of both sets of elements is well-suited to most geological applications. Following a critical appraisal of calibration accuracy, new trace element data are presented for 15 reference samples from the Geological Survey of Japan.  相似文献   

Variations in wind velocity and sand transport on the windward flanks of desert sand dunes   总被引：1，自引：0，他引：1  

ANDREW WATSON 《Sedimentology》1987,34(3):511-520

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CENTRALITY AND CITIES. By James Bird.     

M. K. WATSON 《New Zealand geographer》1977,33(2):97-97

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Short-term morphological change and sediment dynamics in the intertidal zone of a macrotidal beach   总被引：1，自引：0，他引：1  

GERHARD MASSELINK  NIGEL AUGER†  PAUL RUSSELL†  TIM O'HARE† 《Sedimentology》2007,54(1):39-53

This paper describes the morphological and sedimentological evolution of a macrotidal beach over a 20 day period under varying hydrodynamic conditions (significant breaker heights of 0·3–2 m and tidal ranges of 2–5 m). During the field campaign, an intertidal bar developed around the mid‐tide level, migrated onshore, welded to the upper beach and was then flattened under energetic wave conditions. The bar had a wave breakpoint origin and its formation was triggered by a reduction in tidal range, causing more stationary water‐level conditions, rather than an increase in wave height. Most of the onshore bar migration took place while the bar was positioned in the inner to mid‐surf zone position, such that the bar moved away from the breakpoint and exhibited ‘divergent’ behaviour. The depth of disturbance over individual tidal cycles was 10–20% of the breaker height. Such values are more typical of steep reflective beaches, than gently sloping, dissipative beaches, and are considered to reflect the maximum height of wave‐generated ripples. The grain size distribution of surficial sediments did not vary consistently across the beach profile and temporal changes in the sedimentology were mostly unrelated to the morphological response. The lack of clear links between beach morphology and sedimentology may be in part due to shortcomings in the sampling methodology, which ignored the vertical variability in the sediment size characteristics across the active layer.  相似文献   

Critical perspectives on integrated water managementEditorial     

NIGEL WATSON  GORDON WALKER  WILL MEDD 《The Geographical journal》2007,173(4):297-299

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The role of Southern Ocean mixing and upwelling in glacial-interglacial atmospheric CO₂ change     

ANDREW J. WATSON  ALBERTO C. NAVEIRA GARABATO † 《Tellus. Series B, Chemical and physical meteorology》2006,58(1):73-87

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The sensitivity of atmospheric CO₂ concentrations to input of iron to the oceans     

ANDREW J. WATSON  NATHALIE LEFÈVRE 《Tellus. Series B, Chemical and physical meteorology》1999,51(2):453-460

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A comparison of multiple regression and neural network techniques for mapping in situ pCO₂ data     

NATHALIE LEFÈVRE †  REW J. WATSON  ADAM R. WATSON 《Tellus. Series B, Chemical and physical meteorology》2005,57(5):375-384

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