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Abdolrahim JAVAHERIAN 《地震学报(英文版)》1994,7(1):23-31
Theoptimumsource-timefunctionforgeneratingfinite-differencesyntheticseismogramsAbdolrahimJAVAHERIAN(InstituteofGeophysics,the... 相似文献
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Wolfgang Horst Michael Börngen Ernst R. flueh 《International Journal of Earth Sciences》1994,83(1):161-169
Out of a dense network of seismic reflection lines for hydrocarbon exploration in the North-east German Basin, several lines were recorded to 12 s TWT to obtain information about the structure of the crust and the crust-mantle transition. One of these profiles is presented here. This stretches for 110 km in a NNE direction between Neustrelitz and the island of Usedom. It reaches from the External Variscides in the south across the North German Massif into the Rügen-Pomorze Terrane in the Baltic Sea. Below Cenozoic-Mesozoic-Paleozoic cover with clear reflections down to base Zechstein, the reflectivity varies considerably with depth and also laterally. The Paleozoic and Precambrian sediments and basement are generally void of reflections, but the lower crust and the Moho show strong reflections. To the north the reflectivity decreases, and the Moho depth increases to beyond the bottom of the record section at 12 s. There are no direct indications for deep-reaching faults such as the Trans-European Fault in the north. The North German Massif acted as a ramp towards the Variscan Orogeny, similar to the London-Brabant Massif further west. 相似文献
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火电厂排放出的粉煤灰,通常作为制砖材料,但若作精加工,可大大提高其经济价值。其中微珠耐高温,可作高温保温充填粉;碳灰含碳量达70%以上,可加工成碳素产品。 相似文献
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The 2-D crustal velocity model along the Hirapur-Mandla DSS profile across the Narmada-Son lineament in central India (Murty et al., 1998) has been updated based on the analysis of some short and discontinuous seismic wide-angle reflection phases. Three layers, with seismic velocities of 6.5–6.7, 6.35–6.40 and 6.8 km s–1, and upper boundaries located approximately at 8, 17 and 22 km depth respectively, have been identified between the basement (velocity 5.9 km s–1) and the uppermost mantle (velocity 7.8 km s–1). The layer with 6.5–6.7 km s–1 velocity is thin and is less than 2-km deep between the Narmada north (at Katangi) and south (at Jabalpur) faults. The upper crust shows a horst feature between these faults, which indicates that the Narmada zone acts as a ridge between two pockets of mafic intrusion in the upper crust. The Moho boundary, at 40–44 km depth and the intra-crustal layers exhibit an upwarp suggesting that the Narmada faults have deep origins, involving deep-seated tectonics. A smaller intrusive thickness between the Narmada faults, as compared to those beyond these faults, suggests that the intrusive activities on the two sides are independent. This further suggests that the two Narmada faults may have been active at different geological times. The seismic model is constrained by 2-D gravity modeling. The gravity highs on either side of the Narmada zone are due to the effect of the high velocity/high density mafic intrusion at upper crustal level. 相似文献
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基于属性数学的工程测量职业技能鉴定综合评价 总被引:1,自引:0,他引:1
探讨了工程测量职业技能鉴定的内容,并建立了鉴定的指标体系,将属性综合评价法应用于技能鉴定评价中,使职业技能鉴定工作科学化、准确化、智能化。 相似文献
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