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91.
介绍了硫铝酸盐“S”型瞬凝水泥干法者漏时使用的配方,阐述了输送工具和扫孔钻具的设计以及灌注工艺技术。 相似文献
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Fazle KARIM 《国际泥沙研究》1999,(2)
1INTRODUCTIONThesouthwesternregionoftheUnitedStates,includingSoutheastArizona,ischaracterizedbyasemiaridclimatewithhotsummers,mildwinters,andephemeralstreamsdrainingsparselyvegetatedareas.ChannelmorphologyoftheephemeralstreamsinSoutheastArizonaisinfluencedbybothlateralandverticalchannelchangesoccurringduringmajorfloods.Lateralchannelchangesoccurinthreewaysbankerosion,meandermigration,andchannelavulsion.Verticalchannelchangesinclude,beddegradationoraggradation,andmayoccurseparatelyorinco… 相似文献
94.
分析了浅埋藏砂岩的成岩环境,并从岩石学、矿物学、同位素及质量平衡估算方面论证硅质碎屑砂岩中的胶结物主要来源于砂岩浅埋藏期间的地下水,进而分析浅埋藏带内地下水的流动机制及早期胶结作用对晚期成岩作用的影响。 相似文献
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Marine cements in mid-Tertiary cool-water shelf limestones of New Zealand and southern Australia 总被引:1,自引:0,他引:1
Large areas of southern Australia and New Zealand are covered by mid‐Tertiary limestones formed in cool‐water, shelf environments. The generally destructive character of sea‐floor diagenesis in such settings precludes ubiquitous inorganic precipitation of carbonates, yet these limestones include occasional units with marine cements: (1) within rare in situ biomounds; (2) within some stacked, cross‐bedded sand bodies; (3) at the top of metre‐scale, subtidal, carbonate cycles; and (4) most commonly, associated with certain unconformities. The marine cements are dominated by isopachous rinds of fibrous to bladed spar, interstitial homogeneous micrite and interstitial micropeloidal micrite, often precipitated sequentially in that order. Internal sedimentation of microbioclastic micrite may occur at any stage. The paradox of marine‐cemented limestone units in an overall destructive cool‐water diagenetic regime may be explained by the precipitation of cement as intermediate Mg‐calcite from marine waters undersaturated with respect to aragonite. In some of the marine‐cemented limestones, aragonite biomoulds may include marine cement/sediment internally, suggesting that dissolution of aragonite can at times be wholly marine and not always involve meteoric influences. We suggest that marine cementation occurred preferentially, but not exclusively, during periods of relatively lowered sea level, probably glacio‐eustatically driven in the mid‐Tertiary. At times of reduced sea level, there was a relative increase in both the temperature and the carbonate saturation state of the shelf waters, and the locus of carbonate sedimentation shifted towards formerly deeper shelf sites, which now experienced increased swell wave and/or tidal energy levels, fostering sediment abrasion and reworking, reduced sedimentation rates and freer exchange of sediment pore‐waters. Energy levels were probably also enhanced by increased upwelling of cold, deep waters onto the Southern Ocean margins of the Australasian carbonate platforms, where water‐mass mixing, warming and loss of CO2 locally maintained critical levels of carbonate saturation for sea‐floor cement precipitation and promoted the phosphate‐glauconite mineralization associated with some of the marine‐cemented limestone units. 相似文献
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98.
Petroleum drill cuttings are usually treated by techniques suitable for particular contaminant groups. The significance of this study consists in the development of a treatment technology that can simultaneously handle the hydrocarbon and metal constituents of drill cuttings. Bioaugmentation is combined with stabilisation/solidification (S/S), within S/S monoliths and in granulated S/S monoliths. Portland cement was used for S/S treatment at 30% binder dosage. Bioaugmentation treatment involved two bacterial densities of a mixed culture bio-preparation. The effects of inclusion of compost, fertiliser and activated carbon were also evaluated. After 28 days, the combined S/S and bioaugmentation treatments recorded up to 15% higher total petroleum hydrocarbon (TPH) loss than control S/S treatment without bioaugmentation. Embedding fertiliser, activated carbon and higher bacterial density within S/S monoliths resulted in the highest (99%) TPH reduction but higher concentrations of metals. The addition of compost and lower bacterial density to granulated S/S monoliths led to similar (98%) TPH degradation and lower amounts of metals. The results suggest that with better mixture optimisation, combining S/S and bioaugmentation could engender more sustainable treatment of drill cuttings. 相似文献
99.
通过对硫氧镁水泥材料进行改性,使其试块在空气中性质稳定,同时获得具有较高的抗压强度。为了对比外加剂对硫氧镁水泥试块抗水性能的影响,试块水养护和空气养护同时进行,并测试3 d、7 d、28 d龄期的抗压强度,试块空气养护28 d后转置入水中养护,取得水对硫氧镁水泥的软化影响(K)。对龄期为28 d样品进行扫描电子显微镜(SEM)微观形貌分析和X-射线衍射(XRD)物相分析。实验结果显示两种外加剂能够有效提高硫氧镁水泥材料的稳定性和抗压性能,同时对提高材料抗水性能有一定的效果。 相似文献
100.
Controlling factors of volumetrically important marine carbonate cementation in deep slope settings 总被引:1,自引:0,他引:1
BRAM VAN DER KOOIJ ADRIAN IMMENHAUSER THOMAS STEUBER JUAN RAMON BAHAMONDE RIONDA OSCAR MERÍNO TOMÉ 《Sedimentology》2010,57(6):1491-1525
The controlling parameters of early marine carbonate cementation in shoal water and hemipelagic to pelagic domains are well‐studied. In contrast, the mechanisms driving the precipitation of early marine carbonate cements at deeper slope settings have received less attention, despite the fact that considerable volumes of early marine cement are present at recent and fossil carbonate slopes in water depths of several hundreds of metres. In order to better understand the controlling factors of pervasive early marine cementation at greater water depths, marine carbonate cements observed along time‐parallel platform to basin transects of two intact Pennsylvanian carbonate slopes are compared with those present in the slope deposits of the Permian Capitan Reef and Neogene Mururoa Atoll. In all four settings, significant amounts of marine cements occlude primary pore spaces downslope into thermoclinal water depths, i.e. in a bathymetric range between some tens and several hundreds of metres. Radial, radiaxial and fascicular optic fibrous calcites, and radiaxial prismatic calcites are associated with re‐deposited facies, boundstones and rudstones. Botryoidal (formerly) aragonitic precipitates are common in microbially induced limestones. From these case studies, it is tentatively concluded that sea water circulation in an extensive, near‐sea floor pore system is a first‐order control on carbonate ion supply and marine cementation. Coastal upwelling and internal or tidal currents are the most probable mechanisms driving pore water circulation at these depths. Carbonate cements precipitated under conditions of normal to elevated alkalinity, locally elevated nutrient levels and variable sea water temperatures. The implications of these findings and suggestions for future work are discussed. 相似文献