| Summary: | Geochemistry and mineralogy work have been taken out on selected shale samples from Siri Canyon in Danish-Norwegian Basin and on Nexø sandstone and basement granite at Bornholm, Denmark. The Late Palaeocene to Early Eocene shales are widely distributed in Siri Canyon located in Danish-Norwegian Basin. Geochemical study on the Late Paleocene-Early Eocene shales has revealed a common provenance of intermediate rocks, and the Rogaland anorthosite complex located in the southwestern Norway is supposed to provide the source materials. The litho-components of Late Paleocene shales were exposed to mediumstrong weathering, and a decrease of weathering degree that probably accompanied with a shift to less oxic depositional environment was observed for the Lower Eocene shales. The change could be related to continental rift that associated with the opening of North Atlantic rifting zone at ~56 Ma. Spatially, there is little elemental variability among the shales from different oil fields, except distinct lower Na contents in shales from the Cecilie field. The transformation of smectite to illite at greater depth in Cecilie filed may release more Na which acts as an interlayer cation in the smectite. The relationships among the weathered Precambrian basement granite, the intercalated pegmatite dykes and the overlying Cambrian Nexø sandstone at Bornholm were defined. The weathered basement granite, pegmatite dyke and sandstone share similar mineralogical compositions of quartz, microline, illite, a small amount of muscovite, hematite and anatase, but vary in mineral proportions. The granite basement has endured medium-strong degree of weathering by comparing to the fresh proto. Mafic minerals and plagioclase have almost totally been decomposed or altered, and primary Fe-Ti minerals were oxidized to hematite and anatase. Major elements show significant depletion in the following order: Na>Ca>Mg; Al and Ti are immobile and stay almost the same amount as those in the fresh rocks; K and Fe show slight enrichment. Trace elements are depleted in the following order: Pb>Sr>U>Ba; Rb shows similar degree of enrichment to K. The pegmatite dyke in the basement granite share similar trace element distribution patterns to those for the basement granite, suggesting a common magma source. In Early Cambrian, the initial flooding at Bornholm started the in-situ deposition of the lower part of Gadeby Member of Nexø sandstone, but the provenance was shifted to distal areas in the local felsic batholith afterwards. Weathering of the Precambrian basement granite was probably involved in a wet and warm climate, and the deposition of Gadeby Member was in an oxic condition that can be related to a shallow fluvial environment. The basement granite plots as A2-type indicative of emplacement in a post-collisional setting at ~1.4Ga, and the Nexø sandstone was deposited in a tectonic setting of passive margin at the early Cambrian. A mineral growth pattern on the surface of Al plate, which is similar to the nucleation process for cements in diagenetic environment, was created in a spray system to protect the substrate more environmentally. Coatings on Al alloy 6060 composed of LiAl-(NO3) hydrotalcite were formed. The coating constitutes of crystals with a typical hydrotalcite structure. Dense and uniform, blade-like flakes completely cover the surface of the Al substrate. The coatings display a multi-layer structure, with a thickness of around 1000 nm. The hydrotalcite coated samples gave better performance than those without coatings in salt spray test, and further treatment with sealing of Mg acetate and dipping into a H2O2+Ce based solution improved the corrosion resistance significantly.
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