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This study investigates the evolution of supra-salt faults in the Eastern Hammerfest Basin using high–quality seismic reflection data. Traditional techniques of displacement analysis, including the variation of fault displacement (throw) against distance (x), depth (z), expansion and growth indices were adopted. Fault reactivation was assessed using bivariate plots of a) cumulative throw vs. age and b) throw (t) vs. depth of nine (9) representative faults.The interpreted faults are supra-salt crestal and synclinal faults striking NE, E and SE. These faults have complicated t-x and t-z plots and are characterized by considerable stratigraphic thickening in their downthrown section. Faults in the study area have developed over the salt structure since latest Paleozoic times; some of them were reactivated by Early to Middle Triassic through dip linkage of initially isolated fault sets. Along strike, the fault exhibit complex segmentation through coalescence of several subunits linked by local throw/displacement minima. Expansion and growth indices show that the faults of the study area developed during the deposition of Paleozoic to Early Cretaceous sediments by polycyclic growth involving both blind and syn-sedimentary activity.An important piece of information from this study is that fault propagation is controlled by lithological heterogeneity and that both lateral and vertical segmentation of faults are important for hydrocarbon migration within the Triassic to Late Cretaceous interval. 相似文献
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《Marine Policy》2015
While there is considerable international research focused on the conservation outcomes of marine protected areas (MPAs) and marine reserves (MRs) there is little information on the economic cost to establish and manage these protected areas. This study estimated the MR pre-establishment and establishment costs for the Taputeranga Marine Reserve (TMR) in New Zealand (NZ) and determined the annual management costs for this reserve and four further NZ MRs. Finally, the cost to local rock lobster fishers resulting from the displaced fishing effort once the TMR had been established was estimated. This research found that the TMR pre-establishment cost was approximately NZ$508,000, and the establishment process cost was approximately NZ$353,000. The annual management costs across the five reserves ranged between NZ$43,200 and NZ$112,500 between 2008/09 and 2010/11. The annual fishers displacement cost at TMR was approximately NZ$22,000 per annum. This research showed that on a unit area basis, small MRs in NZ are just as expensive to maintain as large MRs. This study also highlighted how volunteer effort helped to considerably reduce the monetary cost of the MR pre-establishment process. This research increases our understanding of establishment and management costs, and supports future planning of MRs both within NZ and internationally. 相似文献
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海底管线是海洋油气输运系统的重要组成成分,其稳定性和安全性尤为重要。通过有限元软件ABAQUS,应用Mohr-Coulomb模型,模拟海底裸置与埋置管线自沉过程。通过平衡初始地应力,设置管土接触,考虑重力和浮力作用,进行土体固结分析,计算裸置与埋置管线的土体与管线竖直位移,并进行管线悬跨研究。计算结果显示,对于裸置管线,参数的改变使土体更容易发生塑性屈服,土体的竖直位移量更大;对于埋置管线,当管线埋深较浅、管线上方土体重量不大时,参数的改变使管线平均密度与周围土体密度相差越大土体越容易发生塑性屈服,土体的竖直位移量越大。当管线悬空时,悬跨长度过大易使管线两端支撑土体被压溃,管线易产生大变形而失稳,因此在管线安装与维护过程中,一定要采取措施降低悬跨长度,保证管线运营安全。 相似文献
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以具体的沉降观测项目和水平位移观测项目为示例,探讨了建筑物变形分析系统ST 5.5在建筑物变形测量中的应用。对该系统的功能和使用方法做了详细的阐述说明,并对使用心得做了详尽的介绍,对遇到的一些问题提出了相应的解决方法。 相似文献
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This study's objective was to investigate the Guguan-Xiangong Fault, which lies in the southern Liupanshan area, through satellite image interpretation and field observations. Guguan-Xiangong Fault is divided into five subsegments; among these, the Badu-Longwei segment has been the most recently active. The geomorphic features of the Badu-Longwei segment are clearly displayed, including multiple high fault scarps with fresh bedrock free faces. There is significant evidence for Holocene activity of the three fault sections, located in Renhuashu, Tianjiagou, and Xinjiecun respectively. The three sections feature distinct episodic deposition and fault scratches. Based on 14 Cdating and field observations on the three fault sections, two or more paleoearthquakes across the Badu-Longwei fault segment are ascertained, between 5874±116 and 5430±140 a BP, and after 2037±83 a BP respectively. The Badu-Longwei segment of the Guguan-Xiangong Fault is preliminarily extrapolated as the seismogenic structure of the 600 A.D. Qin-Long earthquake. 相似文献