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871.
Susan Stirling 《New Zealand geographer》2008,64(1):68-71
Abstract: This paper considers three questions: Why are fieldtrips used in geography? How does this mesh with the geographers’ own understandings of geography? What do lecturers hope to achieve on fieldtrips? Understandings are gleaned from interviews with those who run fieldtrips. There has been a tradition of fieldtrips in New Zealand and this very tradition helps to maintain them. Fieldtrips are shaped by geographers’ particular philosophical approaches to geography and take different approaches according to their aims. 相似文献
872.
Resin‐impregnated sediment blocks are a by‐product of micromorphological sample processing. These blocks can be further studied using a variety of destructive, nondestructive, and minimally destructive geochemical techniques. X‐ray fluorescence microanalyses conducted on sediment blocks yield semiquantitative major and trace elemental abundances that can be used to generate compositional maps, and to illustrate compositional change within or between archaeological strata and features. Sediment blocks can also be drilled to obtain small sediment samples for stable oxygen and carbon isotopic analyses. Both elemental and isotopic analyses can be conducted in conjunction with micromorphological analyses to yield a holistic picture of archaeological sediment composition, source, and depositional processes. The integration of micromorphological, compositional, and isotopic analyses is used here to aid in the differentiation of calcareous ash and lime plasters from the Neolithic site of Asıklı Höyük, Turkey. 相似文献
873.
Susan H. Treagus 《Geological Journal》1982,17(1):49-64
Traditional methods of studying natural folds are reviewed. A new method of describing cleavage attitude in folds is presented; the β plot. The combined graph of dip isogon angle ϕ (Hudleston 1973) and cleavage angle β is proposed as a linked classification of fold and cleavage geometry. Plots of β and βϕ are given for three natural fold examples. The classification is extended to the geometry and strain attitude (βϕ5) of two finite-element models and the classical folding models. Results are compared and some tentative conclusions drawn on the relationship of cleavage, the XY plane of strain and dip isogons. 相似文献