The Total Internal Reflection of SH Waves     

J. A. Hudson 《Geophysical Journal International》1962,6(4):509-531

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Paleolimnological investigations of anthropogenic environmental change in Lake Tanganyika: VII. Carbonate isotope geochemistry as a record of riverine runoff     

David?L.?DettmanEmail author  Manuel?R.?Palacios-Fest  Hudson?H.?Nkotagu  Andrew?S.?Cohen 《Journal of Paleolimnology》2005,34(1):93-105

Evaporation dominates the removal of water from Lake Tanganyika, and therefore the oxygen isotope composition of lake water has become very positive in comparison to the waters entering the lake. The surface water in Lake Tanganyika has remained relatively unchanged over the last 30 years with a seasonal range of +3.2 to +3.5 VSMOW. Water from small rivers entering the lake seems to have a ¹⁸O value between –3.5 and –4.0, based on scattered measurements. The two largest catchments emptying into the lake deliver water that has a ¹⁸O value between these two extremes. This large contrast is the basis of a model presented here that attempts to reconstruct the history of runoff intensity based on the ¹⁸O of carbonate shells from Lake Tanganyika cores. In order to use biogenic carbonates to monitor changes in the ¹⁸O of mixing-zone water, however, the oxygen isotope fractionation between water and shell carbonate must be well understood. The relatively invariant environmental conditions of the lake allow us to constrain the fractionation of both oxygen and carbon isotope ratios. Although molluskan aragonitic shell ¹⁸O values are in agreement with published mineral-water fractionations, ostracode calcite is 1.2 more positive than that of inorganic calcite precipitated under similar conditions. Ostracode shell ¹⁸O data from two cores from central Lake Tanganyika suggest that runoff decreased in the first half of this millennium and has increased in the last century. This conclusion is poorly constrained, however, and much more work needs to be done on stable isotope variation in both the waters and carbonates of Lake Tanganyika. We also compared the ¹³C of shells against predicted values based solely on the ¹³C of lake water dissolved inorganic carbon (DIC). The ostracode Mecynocypria opaca is the only ostracode or mollusk that falls within the predicted range. This suggests that M. opaca has potential for reconstructing the carbon isotope ratio of DIC in Lake Tanganyika, and may be a useful tool in the study of the history of the lakes productivity and carbon cycle.  相似文献   

The WISERD Geoportal: A Tool for the Discovery,Analysis and Visualization of Socio‐economic (Meta‐) Data for Wales     

Richard Fry  Robert Berry  Gary Higgs  Scott Orford  Sam Jones 《Transactions in GIS》2012,16(2):105-124

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Abundance ratios in red-sequence galaxies over a wide mass range: the 'X-planes' for magnesium, calcium, carbon and nitrogen     

Russell J. Smith  John R. Lucey  Michael J. Hudson  Terry J. Bridges 《Monthly notices of the Royal Astronomical Society》2009,398(1):119-132

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The Jurassic Coast Story Book: An approach to geoheritage interpretation from the Jurassic Coast World Heritage Site     

Sam Scriven 《Proceedings of the Geologists' Association. Geologists' Association》2019,130(3-4):493-506

The World Heritage status of the Jurassic Coast has important implications for how the geoheritage of the site is communicated to audiences. UNESCO defines World Heritage Sites as places with Outstanding Universal Value to all people that must be preserved for future generations. Building relationships between people and place is key to conservation and on the Jurassic Coast that is delivered by providing audiences with physical, intellectual and emotional access to the Site. Heritage interpretation offers an effective way to develop these connections and create diverse ways for people to engage with the unique Earth Science stories that underpin the World Heritage Status of the Dorset and East Devon Coast. This paper reflects on the approach to interpretation taken by the Jurassic Coast Team and explores the ways in which geoheritage is a challenging subject to interpret. Practitioners on the Jurassic Coast have more recently developed an interpretive approach to help overcome these difficulties. Three categories of geoheritage stories were identified (Landscape, Cultural geology and Earth History) and three interpretive principles were devised (perspective, intimacy and imagination) as a way of scoping out a relevant emotional context for interpretive content. This approach laid the foundation for the development of a new interpretation framework for the Jurassic Coast – The Jurassic Coast Story Book, which will be subject to ongoing testing and evaluation by the new organisation leading on the protection and promotion of the Jurassic Coast World Heritage Site; Jurassic Coast Trust.  相似文献   

The reflection of charged particles by rotational discontinuities     

P.D. Hudson 《Planetary and Space Science》1974,22(11):1571-1577

This paper investigates the reflection and transmission of charged particles incident on a rotational discontinuity whose thickness is small compared to their Larmor radius. This is done for the full range of parameters likely to occur for rotational discontinuities in the solar wind. Usually the proportion of particles reflected is similar to that predicted by adiabatic theory, except when the magnetic field ratio is close to unity, or the bend in the fieldlines is large.  相似文献   

The general geology and topography of the Harrogate district     

R.G.S. Hudson 《Proceedings of the Geologists' Association. Geologists' Association》1938,49(3):295-305

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“The scenery and geology of the Yorkshire Dales.”     

R.G.S. Hudson 《Proceedings of the Geologists' Association. Geologists' Association》1933,44(3):1-5

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The Yorkshire Dales. The summer field meeting, 1933     

R.G.S. Hudson  W.B.R. King 《Proceedings of the Geologists' Association. Geologists' Association》1933,44(4):428-IN5

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The carboniferous of the Craven Reef Belt: The Namurian Uncomformity at Scaleber,Near Settle     

R.G.S. Hudson 《Proceedings of the Geologists' Association. Geologists' Association》1930,41(3):290-IN8

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