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51.
Predrill overpressure prediction is important for well planning and migration modeling for prospect evaluation. The Eaton (Journal of Petroleum Technology, 24 , 1972, 929) and Bowers (SPE Drilling & Completion, 10 , 1995, 89) methods are used worldwide for postdrill overpressure prediction using sonic log and predrill overpressure prediction using seismic interval velocity. In this research, these two methods were used for overpressure prediction using 3D anisotropic prestack depth‐migrated seismic interval velocity in a field of the Malay Basin. In the shallow overpressured zone, where the mechanism of overpressure is undercompaction, the onset of overpressure was predicted reasonably well using the Eaton and Bowers methods with their standard parameters (i.e., Eaton exponent 3 and Bowers loading curve) for seismic velocity. However, in the deep overpressured zone, where fluid expansion is the cause of overpressure generation, these methods underpredicted the high overpressure. In the deep overpressured zone, the overpressures were better predicted by applying a correction to the Eaton method. On the other hand, the Bowers unloading parameters for the fluid expansion mechanisms did not show any significant effect on overpressure prediction. Hence, in the study area, the Bowers method is not effective for 3D overpressure prediction using seismic velocity, whereas the Eaton method is more robust and can be used for 3D overpressure prediction from seismic velocity. 相似文献
52.
Jase Sitton Christopher Stenzel Briggs Buchanan Metin I. Eren Brett Story 《Archaeometry》2023,65(3):463-479
Many factors governed the penetration efficacy of prehistoric projectile weaponry. Archaeologists broadly focus their efforts on understanding the effect of stone weapon tips because these specimens are often the only part of the weapon system that survives in the archaeological record. The tip cross-sectional area (TCSA) and perimeter (TCSP) of stone weapon tips have been shown to correlate with target penetration depth. Here, using results from both static and dynamic penetration testing, we compare TCSA and TCSP against other tip geometry metrics: lateral surface area (LSA) and volume (V). Our analyses broadly show that using a single-point geometry metric evaluated at multiple locations along the length of the point, or using multiple geometry metrics evaluated at a single location, better predicts required energy than using a single-point geometry metric evaluated at a single location. Our results also show that in the case where a single geometry metric evaluated at multiple locations is used LSA provided the most robust prediction models. Finally, our results show that for the case where all geometry metrics evaluated at a single location are used the location that provides the most robust prediction model is dependent on how far the point penetrated the target. 相似文献
53.
Cities are considered to be the major drivers of the global economy for many reasons, including their creative and innovative potential in generating sustainable economic growth. Istanbul is one of the global cities searching for a long-term growth strategy. This paper starts with a modest effort of composing an index to be used in the evaluation of the creative potential of cities. Our proposed index, “global creative index”, consists of five main criteria: (1) creativeness, (2) innovativeness, (3) intellectual development, (4) global network connectivity and (5) world cityness emphasizing multinational corporate economy, international division of labour and high intensity of producer and financial services. The use of the index is illustrated through the comparison of nine cities: Hong Kong, Istanbul, London, Los Angeles, Moscow, New York, Shanghai, Singapore and Toronto. The analysis of these nine cities shows that Istanbul is building an innovation environment, but it still lacks research and development infrastructure, technical support and investment in higher education. This comparison offers guidelines for policy-makers to sketch the growth of Istanbul along the lines of creativity and innovativeness. 相似文献
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