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81.
孤岛油田属稠油疏松砂岩油藏,生产过程中油井出砂严重,现有的涂敷砂人工井壁防砂注蒸汽后强度较低,造成防砂成功率低,注汽后高强度采液生产周期较短。为此,通过室内试验,优选出耐高温树脂、高强度骨架颗粒、偶联剂、固化剂,进行室内配方优化试验,评价固结体耐高温性能,测定其渗透率,研制出一种适用于疏松砂岩油藏注蒸汽热采井的HD-1注汽井新型防砂材料。在孤岛油田稠油注蒸汽热采区共试验72口井,成功率为91.0%,截止目前,累计产油为121 572 t,单井平均有效期为233 d。现场应用表明:HD-1注汽井新型防砂材料耐高温、强度高,防砂成功率高,有效期长,能够有效改善注蒸汽热采井的防砂效果。  相似文献   
82.
为了解决广西岩溶石山区人畜饮水和农田用水问题 ,需对丰富的地下水资源进行详细勘查和合理开发 ,采取有效措施 ,就能实现岩溶石山区人民的脱贫目标。  相似文献   
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84.
The added value of the joint pre-stack inversion of PP (incident P-wave and reflected P-wave) and PS (incident P-wave and reflected S-wave) seismic data for the time-lapse application is shown. We focus on the application of this technique to the time-lapse (four-dimensional) multicomponent Jubarte field permanent reservoir monitoring seismic data. The joint inversion results are less sensitive to noise in the input data and show a better match with the rock physics models calibrated for the field. Further, joint inversion improves S-impedance estimates and provides a more robust quantitative interpretation, allowing enhanced differentiation between pore pressure and fluid saturation changes, which will be extremely useful for reservoir management. Small changes in reservoir properties are expected in the short time between the time-lapse seismic acquisitions used in the Jubarte project (only 1 year apart). The attempt to recover subtle fourth-dimensional effects via elastic inversion is recurrent in reservoir characterization projects, either due to the small sensitivity of the reservoirs to fluid and pressure changes or the short interval between the acquisitions. Therefore, looking for methodologies that minimize the uncertainty of fourth-dimensional inversion outputs is of fundamental importance. Here, we also show the differences between PP only and joint PP–PS inversion workflows and parameterizations that can be applied in other projects. We show the impact of using multicomponent data as input for elastic seismic inversions in the analysis of the time-lapse differences of the elastic properties. The larger investment in the acquisition and processing of multicomponent seismic data is shown to be justified by the improved results from the fourth-dimensional joint inversion.  相似文献   
85.
小口径绳索取心钻探技术在页岩气地质调查井中具有不可替代的优势,同时也存在较大的局限性。结合小口径绳索取心工艺在10余口页岩气调查井的应用情况,从地质条件、技术要求、设备及配套机具等方面归纳总结了施工中的难点,从井身结构、设备配置、取心工艺、泥浆体系、复杂情况预防等方面提出了优化方案。依据优化后的施工技术措施,在后续施工的页岩气调查井中取得了良好的效果,岩心采取率保持在97%以上,台月进尺超过了400 m,复杂发生频次控制在2次以下。对下一步小口径页岩气调查井施工具有一定的借鉴意义。  相似文献   
86.
岩溶塌陷监测内容及方法概述   总被引:2,自引:0,他引:2  
岩溶塌陷是影响和制约岩溶地区社会、经济发展的主要环境地质问题之一,在我国也不例外.岩溶塌陷监测是岩溶塌陷地质灾害防治中重要内容之一.通过岩溶塌陷监测,可以掌握溶洞随时间的发展变化过程,包括大小、位置、应力强度等,进而为岩溶塌陷预测提供基础数据支撑,避免造成人员和财产损失.本文系统地介绍了目前国内外针对岩溶塌陷问题开展的主要监测工作.从岩溶塌陷的分布规律和形成的3大条件出发,总结出岩溶塌陷监测的内容和相对应的监测技术、方法和手段,为系统性地开展岩溶塌陷监测工作提供技术和方法参考,为更深入地研究岩溶塌陷机理等提供基础支撑.最后,文章指出未来岩溶塌陷监测工作的重点是新兴技术手段和传统监测方法相结合,互补优劣.  相似文献   
87.
The Ramsar-listed wetlands of the Magela Creek floodplain, situated in the World Heritage Kakadu National Park, in northern Australia are recognised for their biodiversity and cultural values. The floodplain is also a downstream receiving environment for Ranger uranium mine, which is entering closure and rehabilitation phases. Vegetation on the floodplain is spatially and temporally variable which is related to the hydrology of the region, primarily the extent and level of inundation and available soil moisture. Time-series mapping of the floodplain vegetation will provide a contemporary baseline of annual vegetation dynamics to assist with determining whether change is natural or a result of the potential impacts of mine closure activities such as increased suspended sediment moving downstream. The research described here used geographic object-based image analysis (GEOBIA) to classify the upper Magela Creek floodplain vegetation from WorldView-2 imagery captured over four years (2010–2013) and ancillary data including a canopy height model. A step-wise rule set was used to implement a decision tree classification. The resulting maps showed the 12 major vegetation communities that exist on the Magela Creek floodplain and their distribution for May 2010, May 2011, June 2012 and June 2013 with overall accuracies of over 80% for each map. Most of the error appears to be associated with confusion between vegetation classes that are spectrally similar such as the classes dominated by grasses. Object-based change detection was then applied to the maps to analyse change between dates. Results indicate that change between dates was detected for large areas of the floodplain. Most of the change is associated with the amount of surface water present, indicating that although imagery was captured at the same time of year, the imagery represents different stages of the seasonal cycle of the floodplain.  相似文献   
88.
Adaptive management of the marine environment requires an understanding of the complex interactions within it. Establishing levels of natural variability within and between marine ecosystems is a necessary prerequisite to this process and requires a monitoring programme which takes account of the issues of time, space and scale. In this paper, we argue that an ecosystem approach to managing the marine environment should take direct account of climate change indicators at a regional level if it is to cope with the unprecedented change expected as a result of human impacts on the earth climate system. We discuss the purpose of environmental monitoring and the importance of maintaining long-term time series. Recommendations are made on the use of these data in conjunction with modern extrapolation and integration tools (e.g. ecosystem models, remote sensing) to provide a diagnostic approach to the management of marine ecosystems, based on adaptive indicators and dynamic baselines.  相似文献   
89.
Diffuse CO<Subscript>2</Subscript> degassing at Vesuvio,Italy   总被引:1,自引:0,他引:1  
At Vesuvio, a significant fraction of the rising hydrothermal–volcanic fluids is subjected to a condensation and separation process producing a CO2–rich gas phase, mainly expulsed through soil diffuse degassing from well defined areas called diffuse degassing structures (DDS), and a liquid phase that flows towards the outer part of the volcanic cone. A large amount of thermal energy is associated with the steam condensation process and subsequent cooling of the liquid phase. The total amount of volcanic–hydrothermal CO2 discharged through diffuse degassing has been computed through a sequential Gaussian simulation (sGs) approach based on several hundred accumulation chamber measurements and, at the time of the survey, amounted to 151 t d–1. The steam associated with the CO2 output, computed assuming that the original H2O/CO2 ratio of hydrothermal fluids is preserved in fumarolic effluents, is 553 t d–1, and the energy produced by the steam condensation and cooling of the liquid phase is 1.47×1012 J d–1 (17 MW). The location of the CO2 and temperature anomalies show that most of the gas is discharged from the inner part of the crater and suggests that crater morphology and local stratigraphy exert strong control on CO2 degassing and subsurface steam condensation. The amounts of gas and energy released by Vesuvio are comparable to those released by other volcanic degassing areas of the world and their estimates, through periodic surveys of soil CO2 flux, can constitute a useful tool to monitor volcanic activity.Editorial responsibility: H. Shinohara  相似文献   
90.
Spis Castle, a monument included in the UNESCO World Heritage Site list (Eastern Slovakia) is built on a travertine mound overlying soft Paleogene rocks. Lateral spreading resulting from the subsidence of strong upper travertine into soft claystone strata has fractured and separated the castle rock into several cliffs. The differential movement of individual cliff faces is the primary influence on the stability of the monument. In order to monitor and quantify the movement, two techniques were adopted: a mechanical-optical TM-71 crack gauge and a demec gauge (demountable mechanical—SOMET type crack gauge). This paper presents the results and interpretation of medium and short-term monitoring at the site.  相似文献   
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