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Prof. Dr. Eugéne Wegmann 《International Journal of Earth Sciences》1964,53(1):314-324
The study of comparative tectonics needs, among other things, a complete catalogue of cataclastic phenomena: not only of their petrographic features, but also of their function and cinematic signification. Every example and case-history added to the presently incomplete list is welcome; and a rarely described variety is here described and placed in the classification. The type-locality is a part of the northern border of the crystalline massif of Alger. In this area the mylonitic breccias have originated relatively near the surface as products of the general movement represented by the elevation of the massif and the depression of the Mediterranean basin along the continental flexure. The general effect is one of extension, but it was accomplished by a series of co-ordinated individual movements. The porosity of the mylonites is greatly increased relative to that of the country rocks. This style of fracturing is important for many geological problems; and some examples are discussed: comparison with similar features in crystallized and granitized regions shows that some phenomena are inherited mylonites from an earlier stage; evolution of volcanic and subvolcanic hybrid rocks and of regenerated metalliferous deposits are only possible in tectonic bodies containing superposed levels or storeys, in these the style of the cataclastic level is especially important. The relationships between folded cover series and “décollements” on the one hand, and the movements of the basement on the other, depend largely on the type of cataclasis which, in turn, may be recognised from its style. 相似文献
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Influence of transient storage on stream nutrient uptake based on substrata manipulation 总被引：3，自引：0，他引：3
Alba Argerich Eugènia Martí Francesc Sabater Roy Haggerty Miquel Ribot 《Aquatic Sciences - Research Across Boundaries》2011,73(3):365-376
Quantification of the transient storage zone (As) has become critical in stream biogeochemical studies addressed to examine factors controlling nutrient uptake. It is expected
that higher As may enhance the interaction between nutrients and biota and thus, increase nutrient uptake. However, results from the literature
are controversial. We hypothesized that besides of the size of As, the intrinsic physical and biological characteristics of stream structures that generate As are also relevant for nutrient uptake. We performed 24 additions of phosphate, ammonium, and chloride in four reaches of
a man-made channel where we introduced three types of naturally colonized substrata packs (mud, sand and cobbles) to modify
As. We estimated ammonium and phosphate uptake coefficients in both the main channel and As using a solute transport model (OTIS-P) and compared the results among reaches with different substrata types. The introduction
of substrata packs decreased water velocity and increased As similarly among treatments. Nutrient uptake coefficients in the main channel were similar among reaches with different type
substrata packs; however, nutrient uptake coefficients measured in As differed among them as well as the ratio between ammonium and phosphorus uptake coefficients in As, which were 1.6 in reaches with mud packs and 0.02 in reaches with sand or cobble packs. Results obtained in this study suggest
that the contribution of As in nutrient uptake not only depends on the size of As but on the type of materials used to increase As, and thus, have biogeochemical implications on restoration projects aimed to modify channel morphology. 相似文献
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