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21.
A dielectric logging tool, electromagnetic propagation tool (EPT), was deployed in 2007 in the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well (Mount Elbert Well), North Slope, Alaska. The measured dielectric properties in the Mount Elbert well, combined with density log measurements, result in a vertical high-resolution (cm-scale) estimate of gas hydrate saturation. Two hydrate-bearing sand reservoirs about 20 m thick were identified using the EPT log and exhibited gas-hydrate saturation estimates ranging from 45% to 85%. In hydrate-bearing zones where variation of hole size and oil-based mud invasion are minimal, EPT-based gas hydrate saturation estimates on average agree well with lower vertical resolution estimates from the nuclear magnetic resonance logs; however, saturation and porosity estimates based on EPT logs are not reliable in intervals with substantial variations in borehole diameter and oil-based invasion.EPT log interpretation reveals many thin-bedded layers at various depths, both above and below the thick continuous hydrate occurrences, which range from 30-cm to about 1-m thick. Such thin layers are not indicated in other well logs, or from the visual observation of core, with the exception of the image log recorded by the oil-base microimager. We also observe that EPT dielectric measurements can be used to accurately detect fine-scale changes in lithology and pore fluid properties of hydrate-bearing sediments where variation of hole size is minimal. EPT measurements may thus provide high-resolution in-situ hydrate saturation estimates for comparison and calibration with laboratory analysis. 相似文献
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重磁3D物性反演技术在金属矿勘探中的应用 总被引:1,自引:0,他引:1
解反演问题是地球物理资料处理解释的主要环节.反演就是依据已获得异常特征,结合地质和其他资料,求解地下源体的空间位置、形状及物性特征参数.随着对地质体全方位精细结构研究要求的提高,重磁等反演技术已发展到3D反演阶段.重磁反演主要有两种方法,即形态反演(建立场源模型形态单元)和物性反演(构建物性模型单元).在物性模型构建中... 相似文献
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In order to know about the rheological properties of rock in a long range of the time scale,method of increasing temperature was brought forward to accelerate the rheological process of rock,which could extend the time scale of experimental test data.Firstly,based on the generalized linear viscoelastic constitutive equation with temperature variable,the creep behavior of rock was divided into three types according to the different strain dependences of the time,that is,Hookean deformation,Newtonian flow,and retarded elasticity.Then the general equivalence relationship between time parameter and temperature parameter was derived for each type of strain.Finally,the relation between time parameter and temperature parameter in the whole creep was considered and the general theory of time-temperature equivalence effect(TTEE) of rock was established.This research reveals: ①The temperature effect on the instantaneous strain could be modified through vertical shift.②The key point of the TTEE of Newtonian flow depends on whether in the study of linear viscoelastic behavior of rock change of temperature is completely equivalent to a shift of the logarithmic time scale or not.③By plotting the results of a creep experiment performed at different temperatures and comparing the curves obtained,one can decide whether the rock considered have TTEE.④The TTEE of the whole creep should satisfy that the horizontal shift function of Newtonian flow and retarded elasticity is consentaneous. 相似文献
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竖向质量分布对框架结构动力特性影响的研究 总被引:2,自引:0,他引:2
在框架结构动力分析中,往往是把填充墙质量集中在楼层处进行求解.文中考虑填充墙实际分布对结构自振特性的影响,通过传递矩阵法求解结构自振频率和振型,并进一步分析了高阶频率的分布规律.结果表明,与采用集中质量模型的振型叠加法相比,填充墙的竖向质量分布会对框架结构高阶频率产生很大影响;框架结构的高阶模态具有局部性和密集分组的特... 相似文献
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针对火山岩风化壳储层控制因素和成因复杂的难题,以三塘湖盆地石炭系卡拉岗组为例,在搞清晚石炭世构造环境和岩性特征基础上,提出风化淋滤和断裂改造是火山岩风化壳形成有利储层的主要控制因素.不同火山岩岩性经风化淋滤后储层物性均增大并能形成有利储层,储集层孔隙类型以次生溶蚀孔隙和裂缝为主,具双峰分布特征.建立了5层结构模型,并提... 相似文献
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《Marine Policy》2015
Recent changes in marine policy in Panama are closely related to sustained expansion of the Panamanian economy in the past ten years. Important drivers of economic growth such as the Panama Canal expansion, tourism, and real estate development directly involve marine and coastal areas. Therefore, maintaining the quality of these environments, as well as the sustainability of the human communities that depend on them, calls for the implementation of adequate management and planning policies. In light of a complex history of marine and coastal policy in Panama, current institutional restructuring processes, and a growing recognition of the importance of marine and coastal geographies, the authors aim to document the current status of, and community response to, marine and coastal policy in Panama, analyzed in terms of three important cross-cutting sectors: tourism, fishing, and conservation. To do so, the authors introduce two case studies: one in the Pearl Islands Archipelago and one in Bocas del Toro, each with varying degrees of participation or involvement in each sector, to illustrate the range of adaptations to change occurring in coastal communities. Based on an in-depth policy analysis and the case studies, the authors suggest that there are important administrative and structural gaps in the legislation and institutions that enforce them, as well as a lack of integration across institutions. In particular, the authors highlight the lack of clear marine and coastal property regimes as an obstacle to the implementation of integrative marine policies in Panama. 相似文献
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绿泥石包壳对碎屑岩储层物性的影响及其形成环境--以鄂尔多斯盆地大牛地气田上古生界为例 总被引:1,自引:0,他引:1
以大牛地气田含绿泥石胶结物样品为研究对象,结合国内外研究现状,研究绿泥石包壳的成因及其对储层物性的影响,并探讨其环境指示意义.大牛地气田的绿泥石包壳形成于成岩作用早期,厚10~20 μm,由原生粒间孔的边缘向中心晶形渐好,颗粒渐大.据铁质来源绿泥石包壳可分为原地和异地成因,原地成因由先体黏土矿物和岩屑溶解未排出的富铁流体生成,一般以混层黏土和晶体较小的包壳形式存在;异地成因是富铁矿物及岩屑溶蚀、溶解形成的富铁流体通过河流异地絮凝沉淀生成,结晶充分、晶形好.绿泥石包壳的储层保护机理为:①抑制石英次生加大;②增加矿物颗粒间抗压实强度,抑制压溶作用;③抑制碳酸盐胶结,促进溶蚀作用.大牛地气田的绿泥石包壳主要发育于盒一段(63%)和山二段,当其含量在15%以下时,孔隙度随绿泥石含量的增高呈线性递增.绿泥石包壳可作为三角洲(辫状河三角洲)前缘水下分流河道(水下辫状河道)等强水动力条件的微观相标志. 相似文献
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车镇北带古近系砂砾岩储层成岩作用特征及其对物性的影响 总被引:1,自引:1,他引:0
综合利用岩芯资料、铸体薄片、物性资料及相关分析测试资料,对车镇北带砂砾岩成岩作用特征及其对储层物性的影响进行了研究。研究表明:工区砂砾岩储层成岩作用主要有压实作用、胶结作用、溶蚀作用、灰泥重结晶作用和交代作用;成岩环境经历了中性/弱碱性→酸性→碱性→酸性→碱性的变化,相应的成岩作用序列为:压实作用→长石溶蚀/早期石英加大→碳酸盐胶结/石英溶蚀→长石溶蚀/碳酸盐胶结物溶蚀/晚期石英加大→黄铁矿胶结;区内砂砾岩储集物性较差,储集空间以次生孔缝为主;不同亚相岩相和成岩作用的差异使其储集物性有所不同,扇根主要发育颗粒支撑和杂基支撑砾岩,成岩作用以压实和灰泥重结晶为主,物性较差,发育无效储层;扇中亚相溶蚀作用较为发育,储集物性得到很好地改善,有效储层比例较高;扇缘亚相以胶结作用为主,使物性变差,局部溶蚀作用发育,可成为有效储层。 相似文献