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971.
分析了影响风动潜孔锤钻进效率的影响因素,利用实验数据建立了数学模型,然后根据灰色关联分析法对各影响因素进行敏感性分析,得到各个影响因素与钻进速度的关联程度。利用敏感性分析结果可以针对提高风动潜孔锤钻进效率采取科学措施,更有利于规范管理。  相似文献   
972.
Present Geothermal Fields of the Dongpu Sag in the Bohai Bay Basin   总被引:2,自引:0,他引:2  
The Dongpu sag is located in the south of the Bohai Bay basin, China, and has abundant oil and gas reserves. To date, there has been no systematic documentation of its geothermal fields. This study measured the rock thermal conductivity of 324 cores from 47 wells, and calculated rock thermal conductivity for different formations. The geothermal gradient and terrestrial heat flow were calculated for 192 wells on basis of 892 formation-testing data from 523 wells. The results show that the Dongpu sag is characterized by a medium-temperature geothermal field between stable and active tectonic areas, with an average geothermal gradient of 32.0°C/km and terrestrial heat flow of 65.6 mW/m2. The geothermal fields in the Dongpu sag is significantly controlled by the Changyuan, Yellow River, and Lanliao basement faults. They developed in the Paleogene and the Dongying movement occurred at the Dongying Formation depositional period. The geothermal fields distribution has a similar characteristic to the tectonic framework of the Dongpu sag, namely two subsags, one uplift, one steep slope and one gentle slope. The oil and gas distribution is closely associated with the present geothermal fields. The work may provide constraints for reconstructing the thermal history and modeling source rock maturation evolution in the Dongpu sag.  相似文献   
973.
区域气象干旱评估分析模式   总被引:1,自引:0,他引:1  
为应对全球范围内日益严重的干旱问题,对区域气象干旱相对完整的评估分析模式开展了探讨。提出了从区域气象干旱识别到干旱特征值计算,再到干旱特征多变量分析的3个分析评估步骤。并以渭河流域为例,对研究区域进行了矩形干旱评估单元划分,选取了RDI(Reconnaissance Drought Index)为评估指标对区域内各单元各时段的干旱状态进行了识别,结果与历史记载的干旱年份吻合较好。分别采用了分布拟合、相关系数和Copula函数等统计学方法对区域干旱的干旱特征值(干旱历时、干旱面积、干旱强度和干旱频率)进行了特征分析,得出了一系列的单变量、双变量及多变量特征分析对比结果。通过对各类分布函数的计算和绘图,得到了渭河流域干旱事件发生的条件概率和重现期,形成了一套相对完整的区域干旱评估分析模式。  相似文献   
974.
Harlahu Depression is basically a geological blank area now. Few studies on the formation and distribution of natural gas hydrate have been published, especially the research and understanding of natural gas hydrate reservoir in this area. The borehole QH-2 is located in the western part of Harlahu Depression of South Qilian Basin, and it was the first deep drilling hole for natural gas hydrate investigation in this area, in which Quaternary,Neogene—Paleogene and Triassic strata were drilled. The authors took the core of Triassic reservoir in well QH-2 as the research object to study the reservoir characteristics of Harlahu Depression, through the thin section observation of rock, porosity, permeability, rock density, casting thin section and other physical property tests, as well as the logging data. The research shows that Triassic reservoir of well QH-2 is widely distributed with great thickness. However, the physical property of the reservoir is poor, and most parts of the reservoir were unconventional reservoirs. The fractures are not developed, so it is difficult to form fracture type hydrate and pore type hydrate in the consolidated rock stratum similar to Muli area. While, the thick Quaternary loose sediments and Tertiary strata with relatively developed fissures were developed under the permafrost regions in this area, which may provide a better reservoir space for the formation of natural gas hydrate.  相似文献   
975.
土壤水分是连接地表水循环和能量循环的关键参量,精确获取该参量对于理解气候变化、地表水文过程、地气间能量交换机理等具有重要意义。微波遥感由于其较为合适的探测深度和坚实的理论基础在观测地表浅层土壤水分上具有很大优势,结合反演方法可以获取空间连续的土壤水分含量,有助于更加客观认知土壤水分的时空演变机理。随着微波遥感数据的不断丰富,多种微波遥感土壤水分反演方法相继涌现,为了更好地了解其发展和趋势,本文总结了当前土壤水分微波反演常用的卫星遥感数据并分析其发展趋势,后从主动微波反演、被动微波反演和多源协同反演3个方面梳理了各类土壤水分微波反演方法的原理、发展和优缺点,最终总结出目前微波遥感土壤水分反演方法的发展趋势:即土壤水分微波反演方法的时空普适性逐渐增强、面向高时空分辨率的土壤水分微波协同反演方法快速发展以及土壤水分微波反演方法的智能化水平不断提高。  相似文献   
976.
面向新时期水利行业“补短板”和“强监管”的应用需求,遥感的前沿技术高光谱遥感凭借较高的光谱分辨率和图谱合一等优势,在水生态、水环境等水利行业的应用中发挥了重要作用,同时在水灾害、水资源等层面中也存在着一定的应用潜力。本文介绍了高光谱遥感的成像原理,回顾了成像光谱仪的发展,列举了目前国内外典型的高光谱载荷。重点介绍了高光谱遥感在水利行业的应用进展,包括水华及水生植物监测、水华和水草精确区分、叶绿素浓度反演、悬浮物浓度和泥沙含量定量估算等具体工作。指出高光谱遥感在实时大范围洪涝灾害应急监测、陆表水文参数定量反演等工作存在一定的发展潜力。最后对高光谱遥感在水利行业的应用存在的瓶颈问题进行总结分析并提出展望:多平台高光谱水利要素立体监测与集成技术研发;水利典型地物要素标准波谱数据库构建;水利高光谱遥感信息智能挖掘的理论方法研究。为拓宽高光谱遥感在水利应用中的研究提供参考。  相似文献   
977.
应用地表露头样品的常规有机地球化学分析资料,从有机质丰度、类型、成熟度等方面,对新疆北部布龙果尔地区下石炭统黑山头组暗色泥岩进行评价.研究表明:黑山头组有机碳含量高,经风化校正后达中等烃源岩标准.有机显微组分由腐泥组、镜质组和惰质组组成,有机质类型为Ⅰ、Ⅱ1、Ⅲ型,处于高成熟演化阶段.虽然样品分析结果受地表风化作用影响严重,但该区下石炭统黑山头组暗色泥岩具一定的生烃能力.  相似文献   
978.
Abstract: Three new species of Chresmodidae are described. They belong to two different genera: Chresmoda multinervis sp. nov., Chresmoda shihi sp. nov. and Jurachresmoda sanyica sp. nov.. A study of the forewing venation is provided. Longitudinal veins are mostly parallel; costal area is broad at the basal and narrowing distally; ScP is probably extending close to the wing apex; R is parallel at length to ScP; MA is running close to R, with two long parallel branches; MA branched-off basally; while MP is not branched until the middle of the wing. However, the important basal part of MP and CuP is poorly preserved. In addition, unique fringing hairs on the mid legs of C. shihi sp. nov. and J. sanyica sp. nov. are described and compared with Jurachresmoda gaskelli Zhang, Ren and Shih, 2008.  相似文献   
979.
<正>Superimposed basins in West China have experienced multi-stage tectonic events and multicycle hydrocarbon reservoir formation,and complex hydrocarbon reservoirs have been discovered widely in basins of this kind.Most of the complex hydrocarbon reservoirs are characterized by relocation,scale re-construction,component variation and phase state transformation,and their distributions are very difficult to predict.Research shows that regional caprock(C),high-quality sedimentary facies(Deposits,D),paleohighs(Mountain,M) and source rock(S) are four geologic elements contributing to complex hydrocarbon reservoir formation and distribution of western superimposed basins.Longitudinal sequential combinations of the four elements control the strata of hydrocarbon reservoir formation,and planar superimpositions and combinations control the range of hydrocarbon reservoir and their simultaneous joint effects in geohistory determine the time of hydrocarbon reservoir formation.Multiple-element matching reservoir formation presents a basic mode of reservoir formation in superimposed basins,and we recommend it is expressed as T-CDMS. Based on the multiple-element matching reservoir formation mode,a comprehensive reservoir formation index(Tcdms) is developed in this paper to characterize reservoir formation conditions, and a method is presented to predict reservoir formation range and probability of occurrence in superimposed basins.Through application of new theory,methods and technology,the favorable reservoir formation range and probability of occurrence in the Ordovician target zone in Tarim Basin in four different reservoir formation periods are predicted.Results show that central Tarim,Yinmaili and Lunnan are the three most favorable regions where Ordovician oil and gas fields may have formed.The coincidence of prediction results with currently discovered hydrocarbon reservoirs reaches 97%.This reflects the effectiveness and reliability of the new theory,methods and technology.  相似文献   
980.
<正>Exploration practices show that the Jurassic System in the hinterland region of the Junggar Basin has a low degree of exploration but huge potential,however the oil/gas accumulation rule is very complicated,and it is difficult to predict hydrocarbon-bearing properties.The research indicates that the oil and gas is controlled by structure facies belt and sedimentary system distribution macroscopically,and hydrocarbon-bearing properties of sand bodies are controlled by lithofacies and petrophysical facies microscopically.Controlled by ancient and current tectonic frameworks,most of the discovered oil and gas are distributed in the delta front sedimentary system of a palaeo-tectonic belt and an ancient slope belt.Subaqueous branch channels and estuary dams mainly with medium and fine sandstone are the main reservoirs and oil production layers,and sand bodies of high porosity and high permeability have good hydrocarbon-bearing properties;the facies controlling effect shows a reservoir controlling geologic model of relatively high porosity and permeability.The hydrocarbon distribution is also controlled by relatively low potential energy at the high points of local structure macroscopically, while most of the successful wells are distributed at the high points of local structure,and the hydrocarbon-bearing property is good at the place of relatively low potential energy;the hydrocarbon distribution is in close connection with faults,and the reservoirs near the fault in the region of relatively low pressure have good oil and gas shows;the distribution of lithologic reservoirs at the depression slope is controlled by the distribution of sand bodies at positions of relatively high porosity and permeability.The formation of the reservoir of the Jurassic in the Junggar Basin shows characteristics of favorable facies and low-potential coupling control,and among the currently discovered reservoirs and industrial hydrocarbon production wells,more than 90%are developed within the scope of faciespotential index FPI0.5,while the FPI and oil saturation of the discovered reservoir and unascertained traps have relatively good linear correlation.By establishing the relation model between hydrocarbonbearing properties of traps and FPI,totally 43 favorable targets are predicted in four main target series of strata and mainly distributed in the Badaowan Formation and the Sangonghe Formation,and the most favorable targets include the north and east of the Shinan Sag,the middle and south of the Mobei Uplift,Cai-35 well area of the Cainan Oilfield,and North-74 well area of the Zhangbei fault-fold zone.  相似文献   
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