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排序方式: 共有159条查询结果,搜索用时 218 毫秒
71.
为明确陆梁油田储集层排驱压力对油气成藏及分布的影响作用,基于油田地质条件及成藏模式,设计实验模型,运用成藏物理模拟方法,模拟断层输导下的油气成藏过程,观察现象、 分析结果,揭示了陆梁油田不同储盖组合成藏性能受排驱压力控制,即在注入一定压力下,与断层对接储集层排驱压力较小的储盖组合优先成藏,且含油饱和度较高;与断层对接排驱压力较大的储盖组合成藏较晚难度较大,含油饱和度较低。未与断层对接的储集层,无论其排驱压力大小,均难以成藏。物理模拟实验再现了陆梁油田侏罗系-白垩系成藏过程。 相似文献
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74.
Johnston EL Marzinelli EM Wood CA Speranza D Bishop JD 《Marine pollution bulletin》2011,62(10):2137-2144
Boat harbours are an increasingly common form of artificial habitat. This paper presents a comparative study of contaminants and foulers of a habitat-forming native kelp (Saccharina latissima) in four marinas and four reference locations along the south-west coast of the UK. Fouling of algal laminae was light (<2% cover) in reference locations, while epibiota cover ranged from 25% to 80% of laminae in marinas. Metals associated with antifouling paints were up to six times more concentrated in algal tissues from marinas than from the reference locations. Marinas also carried the greatest cover and diversity of non-indigenous epibiota on the kelp laminae. This indicates not only a potential stress to kelps in these environments, but also the possibility that detached laminae will act as vectors for the dispersal of non-indigenous species. The development of boat harbours creates habitats that are high risk source localities for pollution-tolerant fouling organisms. 相似文献
75.
Concentrations of tributyltin (TBT) and its breakdown products, dibutyltin (DBT) and monobutyltin (MTB), were measured in tissues of male turbot Scophthalmus maximus from the Gulf of Gdańsk (GDA) and the Pomeranian Bay (POM) in the southern Baltic Sea. The fish (n = 206) were collected during the spawning seasons of 2008-2009. All specimens were at the same maturity stage and in full breeding condition. The ripe testes of the turbot appeared to be a target tissue for TBT accumulation. We report that TBT is extensively eliminated at the specific whole-body level and that the males from TBT-contaminated location (GDA) reach this specific level at 23-24 cm in total length. 相似文献
76.
Knowledge of peatland initiation, accumulation, and decline or cessation is critical in understanding peatland development and the related carbon source/sink effect. In this study, we investigated the development of three peat profiles along the eastern margin of the Tibetan Plateau (ETP) and compared the results with those of our previous work along this transect. Our work showed that the initiation over the northern ETP is later and the slowdown/cessation earlier than in the middle to southern ETP. The timing of optimum peatland formation over the northern ETP lags the Holocene climatic optimum. These spatio-temporal differences are likely to be related to the intensity of Asian summer monsoon. Our work suggests that some peatlands along the ETP transect have returned or are now returning their previously captured carbon to the atmosphere and thus act as carbon sources. Some peatlands still have net accumulation at present, but the rates have been reduced concomitant with the decreasing summer monsoon intensity. We speculate that more of the previously stored carbon in the ETP peatlands will be re-emitted to the atmosphere if the aridity continues, as might occur under a continuous global-warming scenario. 相似文献
77.
三塘湖盆地属西部典型的改造型叠合盆地,火山岩油气藏主要分布于石炭系、二叠系火山岩中。本文结合盆地构造演化史与生烃史,分析了三塘湖盆地石炭-二叠纪火山岩油气藏形成的动态过程。火山岩油气藏主要形成于二叠纪末-三叠纪海西印支期和侏罗纪末-白垩纪末期的燕山期,油气藏的形成及后期调整与构造运动密切相关。火山岩油气藏具多期运聚、多期成藏和多期调整改造成藏特征,其成藏模式为以火山岩风化壳为储集层、下覆湖相泥岩为烃源岩,油气在构造背景下,沿不整合面聚集成藏,形成下生上储地层型油藏组合模式。本文结合构造演化史分析三塘湖盆地火山岩油气成藏过程,对西部沉积盆地下组合火山岩油气藏的勘探具有良好借鉴与指导意义。 相似文献
78.
Yan-wu Zhou 《Marine pollution bulletin》2010,60(8):1319-1324
To investigate the influence of mangrove reforestation on heavy metal accumulation and speciation in intertidal sediments, core sediments from a restored mangrove forest and adjacent mud flat in Yifeng Estuary (southeastern China) were analyzed. The chemical speciation of heavy metals (Pb, Zn, Cu, Cr and Ni) was determined according to a sequential extraction procedure. Special attention was paid to the upper 20 cm of sediment, in which metal accumulation was enhanced and speciation was obviously modified. Mangrove reforestation decreased the concentrations of all metals in the acid-soluble fraction and increased metal concentrations in the oxidizable fraction. Increased Pb, Zn and Cu concentrations and decreased Ni and Cr concentrations were observed in the reducible fraction. These results suggest that mangrove reforestation facilitated the accumulation of heavy metals in the upper sediment layers but decreased their bioavailability and mobility. 相似文献
79.
Ahmed A. Abdelhafez Hassan H. Abbas Rafat S. Abd‐El‐Aal Nabil F. Kandil Jianhua Li Wahballah Mahmoud 《洁净——土壤、空气、水》2012,40(4):356-363
Excessive amounts of mineral fertilizers are unnecessarily applied to agricultural soils in Egypt to increase crop yield. The current study aims at assessing the impacts of fertilization with different mineral fertilizers for different cultivation periods on the accumulation of heavy metals in soils and plants grown thereon. In addition, human risks resulted due to the exposure to these metal ions through ingestion, and dermal routes were evaluated. Soil and plant samples were collected from several locations in El‐Behira Governorate, Egypt and their heavy metal contents were measured. The result indicated that there is a continuous accumulation of heavy metals in the soils and the plants grown thereon. Calculation of the hazard index (HI) revealed that humans, especially children, have a potential health risk for both Pb and Cd, which have levels greater than the safe level (1). Finally, the obtained results showed that the continuous application of mineral fertilizers containing high levels of heavy metals pose a potential health threat. 相似文献
80.
An investigation of the geotechnical properties of sediments from 57 boreholes drilled in West Delta and South Pass OSC Lease Areas, offshore Louisiana, indicated that sediment texture, shear strength, water content, and liquid limit vary significantly laterally and with depth. Samples are predominantly soft, fine‐grained sediments with high water content and medium to high plasticity. Firm, coarser‐grained sediments were obtained near the shoreline in South Pass OCS Lease Area and in the northern and eastern parts of West Delta OCS Lease Area. Trends in the distribution of geotechnical properties appear to be influenced by sediment texture and rate of sedimentation. 相似文献