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21.
高精度层序地层学已被证明是寻找隐蔽圈闭行之有效的理论方法.运用该理论对南阳凹陷进行了研究,对地震剖面中反射界面的追踪,在古近系中识别出了各级别的层序界面,结合周缘露头、钻井、测井等资料,分析了主要目的层序内体系域的构成及高频单元变化规律,建立了层序地层模式,在此基础上预测南部陡崖式断坡带和北部缓坡式弯折带是低位域砂体和隐蔽岩性油气藏形成的有利区带.  相似文献   
22.
论油气化探精查技术及其应用   总被引:4,自引:1,他引:4  
油气化探精查技术是在盆地有利聚集区(带)进行化探和石油地质详查的基础上,对圈闭进行含油气性评价并优选钻探目标的化探精细调查技术.它是包含样品采集、实验测试、信息提取和解释评价等为一体的系列技术.简述精查技术产生的背景,在论述化探精查技术及其在中国中东部地区的应用效果的基础上,展望该项新技术在西部油气勘探中的应用前景.  相似文献   
23.
Based on characteristics and trap types of gas reservoirs in large and medium gas fields in China, 4 gas reservoir models have been established:(i) structural trap gas reservoir model I, formed earlier than or simutaneously with generating of gases; (ii) structural trap gas reservoir model II, formed later than generating of gases; (iii) fossil weathered residuum gas reservoir model; and (iV) mud diapir abnormal temperature and pressure gas reservoir model. Distribution patterns of large-medium gas fields are described with the concept of “sealed compartment”. It is concluded that the inner-compartment area, marginal area of the compartment and the areas between two overlapped sealed compartments are the most favourable areas for discovering large-medium gas fields. Project supported by the “85–102” Chinese National Key Science and Technology Project.  相似文献   
24.
油气圈闭与鄂尔多斯盆地北部铀成矿关系探讨   总被引:11,自引:2,他引:11  
鄂尔多斯盆地北部的伊盟隆起区 ,特别是杭锦旗至东胜一带的地层发育大量的圈闭 ,它们是油气聚集成藏的场所。本文剖析了这些圈闭的类型和成因 ,指出它们是盆地北部天然气运移的有利指向区 ,是还原性气体的储存库和重要的扩散源 ;油气渗出和含氧含铀水渗入的交汇部位是铀成矿的有利场所。因此 ,查明圈闭和断裂构造 ,对分析油气运移方向及砂岩型铀矿预测具有实际意义  相似文献   
25.
Resuspension estimates given by two different trap methods in a shallow lake were compared. The sensitivity of the methods to errors in estimates of gross sedimentation and organic fraction of trapped material was explored. The methods were label method, in which resuspension is estimated by determining the organic fraction of surface sediment, suspended seston and trapped material, and SPIM/SPM method, where the relationship between settling particulate inorganic matter (SPIM) and total settling particulate matter (SPM) is used. During the whole 111 day study period, according to the label method, at a sheltered station 1949 g m−2 dry weight of sediment was resuspended, whereas SPIM/SPM gave an estimate of 1815 g m−2. The difference in the estimates was probably due to mineralization loss of organic material in the traps during the two week exposure periods. Sensitivity analysis showed that of the two methods, the label method was more sensitive to variations in the organic content of trapped material. At a wind-exposed station, the total amounts of resuspended matter given by the label method and by the SPIM/SPM method were 4966 g m−2 and 4971 g m−2, respectively. Due to wind effects, escape of trapped material took place, which caused underestimation of gross sedimentation and compensated the effects of mineralization loss to diminish the difference between the methods. Of the two methods, the SPIM/SPM method seems thus more suitable for lakes, where bacterial activity is high. If cyanobacterial blooms take place, the label method is probably more reliable, providing that the exposure time of sediment traps is kept adequately short.  相似文献   
26.
便携式Li-K分析仪的研制及其在锂辉石中锂的分析应用   总被引:1,自引:1,他引:0  
我国锂钾主要矿产资源大多分布在西部偏远地区,其勘查找矿或综合利用迫切需要现场快速分析技术的支持。本文介绍了自行开发的便携式Li-K分析仪的主要性能及其在锂辉石中锂的分析应用。Li-K分析仪是一种基于大气压的液体阴极辉光放电光谱仪,以待测液体为放电阴极,实现了样品中Li、K等元素的原子化和激发。该仪器以光纤传导CCD光谱仪作为检测器,其波长范围为345~1015 nm,分辨率3 nm;以Li 670.78 nm和K 769.90 nm分析谱线,在仪器最佳工作条件下测定Li、K的精密度(RSD,n=14)均低于2%,检出限为0.03μg/m L,检测范围0.1~10μg/m L。研究表明,不同酸度和酸的类型对谱线强度影响较大,且存在显著的样品基体效应,标准曲线法分析锂辉石中Li的结果偏差高达267%;而标准加入法可克服基体效应的影响,获得与ICP-OES一致性较好的分析结果,为现场开展固体样品中Li的测定奠定了基础。  相似文献   
27.
晚白垩世晚期—新生代发育的高邮凹陷,是苏北盆地南部典型富含油气的半地堑式断陷盆地,自南向北分为南断阶、深凹带与北斜坡。该凹陷复杂断裂构造系统与相应的沉积格局受印支期NEE向逆冲基底断层系与晚侏罗世伊泽纳崎板块高速斜向俯冲形成的NNE向左行平移基底断层系影响,同时受古近纪期间区域近SN向拉张应力状态控制。北斜坡东部花瓦构造带主体EW向正断层与NNE向隐蔽性断层发育了限制型、连接型、复合型3类隐蔽性断块圈闭模式,同时在平面上形成多种组合样式。通过研究花瓦区隐蔽性断块圈闭实例与有限差分法数值模拟,分析总结出高邮凹陷NNE向隐蔽性断层的成因机制与构造特征,并推断了5条隐蔽性断层发育带。  相似文献   
28.
Under real sea conditions, the hydrodynamic performance of floating vertical-axis tidal current turbines is affected by waves and currents. The wave circular frequency is a significant factor in determining the frequencies of the wave-induced motion responses of turbines. In this study, the ANSYS-CFX software (manufacturer: ANSYS Inc., Pittsburgh, Pennsylvania, United States) is used to analyse the hydrodynamic performance of a vertical-axis turbine for different yawing frequencies and to study how the yawing frequencies affect the main hydrodynamic coefficients of the turbine, including the power coefficient, thrust coefficient, lateral force coefficient, and yawing moment coefficient. The time-varying curves obtained from the CFX software are fitted using the least-squares method; the damping and added mass coefficients are then calculated to analyse the influence of different yawing frequencies. The simulation results demonstrate that when analysing non-yawing turbines rotating under constant inflow, the main hydrodynamic coefficient time-varying curves of yawing turbines exhibit an additional fluctuation. Furthermore, the amplitude is positively correlated with the yawing frequency, and the oscillation amplitudes also increase with increasing yawing frequency; however, the average values of the hydrodynamic coefficients (except the power coefficient) are only weakly influenced by yawing motion. The power coefficient under yawing motion is lower than that under non-yawing motion, which means that yawing motion will cause the annual energy production of a turbine to decrease. The fitting results show that the damping term and the added mass term exert effects of the same level on the loads and moments of vertical-axis turbines under yawing motion. The results of this study can facilitate the study of the motion response of floating vertical-axis tidal current turbine systems in waves.  相似文献   
29.
建立了利用高效液相色谱-电喷雾离子阱质谱(HPLC-ESI-IT-MS)测定海洋微藻藻粉中8种典型脂溶性毒素的分析方法。藻粉样品经超声细胞破碎后,采用超声波辅助提取法对藻毒素进行提取,用HPLC-ESI-IT-MS多反应离子监测(MRM)模式对各种毒素(包括大田软海绵酸(OA)、鳍藻毒素1(DTX-1)、扇贝毒素2(PTX-2)、虾夷扇贝毒素(YTX)、原多甲藻酸1(AZA1)原多甲藻酸2(AZA2)、罗环内酯毒素(SPX),米氏裸甲藻毒素(GYM))进行测定。8种脂溶性藻毒素均在线性范围内线性关系良好(R2均在0.991以上),检出限均介于0.085~1.315 pg之间,加标回收率在88.5%~111.4%之间,方法重复性相对标准偏差(RSD)在4.82%~10.17%范围。应用该方法对利玛原甲藻干藻粉中的毒素进行了测定,分析结果良好,说明本方法是海洋微藻藻粉中脂溶性藻毒素测定的有效方法。  相似文献   
30.
Sediment traps are an important tool for studying the source, composition and sedimentation processes of sinking particulate matter in the ocean. An in situ observational mooring(TJ-A-1) is located in the northern South China Sea(20.05°N, 117.42°E) at a water depth of 2 100 m and equipped with two sediment traps deployed at 500 m and 1 950 m. Samples were collected at 18-day intervals, and 20 samples were obtained at both depths from May 2014 to May 2015. Large amounts of fecal matter and marine snow were collected in the lower trap. The fluxes of marine snow and fecal pellets exhibited a fluctuating decrease between May 2014 and early August 2014 and then stabilized at a relatively low level. Scanning electron microscopy observations revealed that the main components of the marine snow and fecal pellets were diatoms, coccolithophores, radiolarians, and other debris, all of which are planktons mostly produced in photic zone. Used in conjunction with the particle collection range estimates from the lower trap and data on ocean surface chlorophyll, these marine snow and fecal pellets were related to the lateral transport of deep water and not vertical migrations from overlying water column. Moreover, the source area might be southwest of Taiwan.  相似文献   
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