Folding of Viscous Plumes Impinging On A Density Or Viscosity Interface   总被引：1，自引：0，他引：1  

R. W. Griffiths  J. S. Turner 《Geophysical Journal International》1988,95(2):397-419

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Book review     

Allen F. Glazner  John C. Griffiths  Betty L. Gibbs 《Mathematical Geology》1988,20(6):753-761

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Deflection of plumes by mantle shear flow: experimental results and a simple theory   总被引：4，自引：0，他引：4  

Mark A. Richards  Ross W. Griffiths 《Geophysical Journal International》1988,94(3):367-376

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THE REMANENT MAGNETISM OF VARVED CLAYS FROM SWEDEN     

D. H. Griffiths 《Geophysical Journal International》1955,7(S3):103-114

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Multi-indicator conductivity transfer functions for Quaternary palaeoclimate reconstruction     

Jane M. Reed  Francesc Mesquita-Joanes  Huw I. Griffiths 《Journal of Paleolimnology》2012,47(2):251-275

Diatoms (Bacillariophyceae; single-celled algae) and ostracods (Ostracoda; shelled microcrustacea) are known for their sensitivity to salinity. In palaeolimnology, the potential has yet to be tested for quantifying past salinity, lake level, and by inference, climate change, by application of multiple-indicator transfer functions. We used weighted averaging techniques to derive diatom (n = 91; r ²  = 0.92) and ostracod (n = 53; r ²  = 0.83) conductivity transfer functions from modern diatom, ostracod and water chemistry data collected in lakes of central, western and northern Turkey. Diatoms were better represented across the full gradient than ostracods, at intermediate levels of conductivity in particular, but both transfer functions were statistically robust. Because transfer functions are not infallible, we further tested the strength and simplicity of salinity response and the potential for identifying characteristic associations of diatom and ostracod taxa in different parts of the salinity gradient, to improve palaeoclimate reconstruction. We identified a subset of 51 samples that contained both diatoms and ostracods, collected at the same time from the same habitat. We used Two-Way Indicator Species Analysis of a combined diatom-ostracod data set, transformed to achieve numerical equivalence, to explore distributions in more detail. A clear ecological threshold was apparent at ~3 g l⁻¹ salinity, rather than at 5 g l⁻¹, the boundary used by some workers, equating to the oligosaline-mesosaline boundary. Other salinity boundaries were poorly defined, indicating lack of a simple, well-defined salinity response. We did, however, define characteristic associations of taxa, to facilitate the distinction to be drawn between a hydrologically open, fresh lake and an oligosaline lake, in palaeoenvironmental reconstruction. Over the rest of the salinity gradient, we highlighted the potential for the multi-proxy approach to strengthen ostracod-based reconstruction in particular, to overcome the problem of broad apparent tolerance ranges in common halophilic taxa such as Limnocythere inopinata, which often dominate in low-diversity fossil assemblages. The combination of multi-proxy quantitative reconstruction, complemented by qualitative understanding of ecological responses generated by the analysis, remains a powerful tool in Quaternary palaeoclimate research.  相似文献   

RXTE monitoring observations of Markarian 3     

I. Georgantopoulos  I. Papadakis  R. S. Warwick  D. A. Smith  G. C. Stewart  R. G. Griffiths 《Monthly notices of the Royal Astronomical Society》1999,307(4):815-820

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Middle Pleistocene deposits at Frog Hall Pit,Stretton-on-Dunsmore,Warwickshire, English Midlands,and their implications for the age of the type Wolstonian     

D. H. Keen  G. R. Coope  R. L. Jones  M. H. Field  H. I. Griffiths  S. G. Lewis  D. Q. Bowen 《第四纪科学杂志》1997,12(3):183-208

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A personal memorial: Peter Zoutendyk (born 23 April 1934; died 15 June 2017)     

John Field  Charles Griffiths 《African Journal of Marine Science》2017,39(2):233-234

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Spatial and temporal influences of in-stream factors on the chemistry and epilithic biomasses of upland stream metal deposits     

Katrina Ann Macintosh  David Griffiths 《Aquatic Sciences - Research Across Boundaries》2014,76(3):331-338

The density and composition of stream bed metal deposits are affected by physical, chemical and biological processes. In this paper we investigate the importance of these processes and their relation to algal and non-photosynthetic detrital (NPD) biomass in a set of upland streams in Northern Ireland. Deposit density and Fe, Mn, Al and P concentrations varied with stream pH across sites but not seasonally. No effects of stream bed erosion or photoreduction were detected on deposit densities. Seasonal variation in stream water metal concentrations was correlated with rainfall. NPD biomass was a significant predictor of both spatial and seasonal variation in deposit concentrations. There were strong, non-linear, relations between NPD biomass and deposit metal concentrations, with Fe and Mn becoming relatively more important and algal biomass declining above threshold deposit/NPD densities. The results suggest that NPD biomass influences deposit density and reduces the biomass of photosynthetic autotrophs above a threshold deposit density.  相似文献   

The morphology and hydrology of small spring-dominated channels     

Ronald E. Griffiths  Diana E. Anderson  Abraham E. Springer   《Geomorphology》2008,102(3-4):511-521

Small, low order channels located in wet meadows along the Mogollon Rim of northern Arizona that receive the bulk of their flow from spring discharge exhibit a morphology that differs markedly from channels that receive the bulk of their flow from runoff. These small, spring-dominated channels generally have dense vegetation cover, vertical (or near vertical) banks with flat channel beds that are armored with clasts up to 60 mm. Clasts armoring the spring-dominated channels become mobile at 45 to 85% of the bankfull depth. The lack of fine-grained material in the bed of the spring-dominated channels reflects the small drainage size, lack of fine grain input from the spring, and winnowing affect of the consistent discharge. Minor amounts of large woody debris were present in some of the spring-dominated channels, however, unlike previous studies it does not appear to play a role in the spring-dominated channel morphology. Sinuosity values for spring-dominated channels averaged 1.19, while the average sinuosity values for the runoff-dominated channels, 1.08, were significantly lower. Measured width-to-depth ratios averaged 2.4 in the spring-dominated channels, much lower than the average ratio of 11.6 found for the runoff-dominated channels. The standard deviation of width-to-depth ratios was higher for runoff-dominated channels, reflecting a more variable channel profile. A third channel type, here referred to as hybrid channels, receive significant flow from both springs and runoff. These channels have characteristics that fall between spring-dominated and runoff-dominated channels.Elevation, gradient, organic matter content, and sediment grain size distribution of the wet meadows in which the channels are formed do not exhibit significant differences between channel types, suggesting that these factors are not responsible for the observed differences in channel morphologies. The major differences in controls on the channel morphology found between the spring-dominated and runoff-dominated channels are the discharge regime and the sediment input. The hydrology unique to the spring-dominated channels and the lack of fine-grained sediment input combine to create the observed differences.  相似文献