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131.
合肥盆地石炭系—二叠系具有油气勘探潜力,但研究薄弱。根据盆地中部安参1井石炭系—二叠系储层中流体包裹体的岩相学分析及显微测温,主要讨论了油气运移特征。结果表明,储层石英微裂隙及次生加大边中与油气包裹体伴生的盐水包裹体均一温度主要在145.2~150.2℃,155.6~160℃及169.9~177.9℃等三个温度区间。结合储层埋藏史-热史,发现储层主要经历了3期流体充注,时间在162.1~157.2 Ma之间(晚侏罗世)。通过包裹体冰点的测定,得到每一期流体的盐度特征,结合构造演化、烃源岩发育背景,推测油气主要是在石炭系—二叠系地层内部运移,同时也可能有新元古界、下古生界等深部的热液通过深大断裂运移到石炭系—二叠系,参与了油气的运聚,这在研究区今后的油气成藏研究中需要注意。  相似文献   
132.
陆相致密油和页岩油同属低孔低渗油气藏,二者具有很大相似性,常具有共生关系,然而其成藏特征存在较大的差异,不加区分极易误导油气勘探.利用系统取心、测井、录井和各类测试化验分析资料,综合分析渤海湾盆地黄骅坳陷孔店组、沙河街组,梳理致密油和页岩油的成藏条件及其富集规律差异性,进一步探讨致密油与页岩油勘探选区评价方法.研究结果...  相似文献   
133.
Based on analysis of geophysical data such as core observation, rock slices identification, physical property, scanning electron microscope, X-ray diffraction, logging data etc., 16 factors of sedimentation, diagenesis, fluid pressure, and their relationships with reservoir physical property were analyzed, and the results indicate sedimentation is the internal factor controlling the reservoir property, diagenesis is the external and final decisive factor and abnormal fluid pressure is an important factor preserving the deep reservoir property. Quantitative characterization of diagenesis indicates that compaction and dissolution are more important than cementation and they respectively cause porosity change of ?23.6% and 7.7% and ?6.2%. Through optimizing 11 main controlling factors and constructing reservoir evaluation index (REI) according to the hierarchical cluster and principal component analysis, reservoir classification standard was established and reservoirs were divided into four classes. The studies show that Es32SQ4 consists mainly of class I and II, while Es32SQ6 is mainly of class III and II; the favorable zone is the north and south slope of Qibei sub-sag and the Liujianfang fault-nose. The successful application of the quantitative and comprehensive evaluation in the Qibei area verifies the advanced, practicable method of less artificial factor is suitable for the low porosity and permeability reservoir.  相似文献   
134.
The long‐term and large‐scale soil moisture (SM) record is important for understanding land atmosphere interactions and their impacts on the weather, climate, and regional ecosystem. SM products are one of the parameters used in some Earth system models, but these records require evaluation before use. The water resources on the Qinghai–Tibet Plateau (QTP) are important to the water security of billions of people in Asia. Therefore, it is necessary to know the SM conditions on the QTP. In this study, the evaluation metrics of multilayer (0–10, 10–40, and 40–100 cm) SM in different reanalysis datasets of the European Centre for Medium‐Range Weather Forecasts interim reanalysis (ERA‐Interim [ERA]), National Centers for Environmental Prediction Climate Forecast System and the Climate Forecast System version 2 (CFSv2), and China Meteorological Administration Land Data Assimilation System (CLDAS) are compared with in situ observations at 5 observation sites, which represent alpine meadow, alpine swamp meadow, alpine grassy meadow, alpine desert steppe, and alpine steppe environments during the thawing season from January 1, 2011, to December 31, 2013, on the QTP. The ERA SM remains constant at approximately 0.2 m3?m?3 at all observation sites during the entire thawing season. The CLDAS and CFSv2 SM products show similar patterns with those of the in situ SM observations during the thawing season. The CLDAS SM product performs better than the CFSv2 and ERA for all vegetation types except the alpine swamp meadow. The results indicate that the soil texture and land cover types play a more important role than the precipitation to increase the biases of the CLDAS SM product on the QTP.  相似文献   
135.
In this study, the Alaska pollock protein isolate(APPI) was hydrolyzed by Neutrase for 20, 40, 80, 120, 160, 200, and 240 min. Hydrolysates with different molecular weights were produced and they were named as H1–H7. Furthermore, the effects of hydrolysis on the average molecular weights, functional properties(solubility, oil-holding capacities, foaming activities, and emulsifying properties), and antioxidant activities(1, 1-diphenyl-2-picrylhydrazyl, superoxide, and hydroxyl free radical-scavenging activities) were determined. It was found that when the degree of hydrolysis(DH) increased, the average molecular weights of the hydrolysates decreased significantly. The functional properties of APPI were also significantly improved. The hydrolysates of APPI exhibited better solubility, emulsifying activities, and foaming activities. Hydrolysates with low molecular weights(1 kDa) had better solubility, oil-holding capacities, and emulsifying activities, while hydrolysates with higher molecular weights(1 kDa) had better foaming activities. In addition, the hydrolysates exhibited excellent antioxidant properties, while the inhibition values of 1, 1-diphenyl-2-picryl hydroxyl(DPPH), superoxide, and hydroxyl free radical-scavenging activities, were 85.22%, 53.56%, and 75.00% respectively, when the concentration of the hydrolysates was 5.0 mg mL~(-1). The lower the average molecular weight was, the higher was the antioxidant activity. These results indicated that hydrolysis with Neutrase is an effective method for improving the functional and antioxidant properties of APPI. The hydrolysates of APPI displayed great potentials to be used as natural antioxidants in protein-rich aqueous foods such as nutrient supplements and sports beverages.  相似文献   
136.
The 3D structure of the tide-induced Lagrangian residual current was studied using the particle image velocimetry (PIV) technique in a long shallow narrow tank in the laboratory. At the mouth of the tank, a wave generator was used to make periodic wave which represents the tide movement, and at the head of the tank, a laterally sloping topography with the length of one fifth of the water tank was installed, above which the tide-induced Lagrangian residual current was studied. Under the weakly nonlinear condition in the present experiment setup, the results show that the Lagrangian residual velocity (LRV) field has a three-layer structure. The residual current flows inwards (towards the head) in the bottom layer and flows outwards in the middle layer, while in the surface layer, it flows inwards along the shallow side of the sloping topography and outwards along the deep side. The depth-averaged and breadth-averaged LRV are also analyzed based on the 3D LRV observations. Our results are in good agreement with the previous experiment studies, the analytical solutions with similar conditions and the observational results in real bays. Moreover, the volume flux comparison between the Lagrangian and Eulerian residual currents shows that the Eulerian residual velocity violates the mass conservation law while the LRV truly represents the inter-tidal water transport. This work enriches the laboratory studies of the LRV and offers valuable references for the LRV studies in real bays.  相似文献   
137.
本文介绍了朝鲜民主主义人民共和国安州煤矿页岩的矿物成分和膨胀性质试验结果。测试结果表明,该页岩具有密度大、孔隙比小和亲水性粘土矿物含量高的特点。这种矿物组成和物理性质决定了它将表现出膨胀变形和膨胀力大的工程特性。因此,认为减少扰动和保持原始含水量可能是防止围岩破坏性膨胀的有效途径。本文是我所和朝鲜同行之间的第一次实质性合作研究成果。  相似文献   
138.
盐湖相烃源岩单体烃硫同位素分布特征和影响因素研究薄弱.采用气相色谱-电感耦合等离子体质谱,结合色谱/质谱、微量元素以及碳氧同位素技术,对东濮凹陷北部盐湖相烃源岩进行了分析.结果 表明,不同单体含硫化合物的δ34S值有较大差异,以δ34S=25.00‰为界,将烃源岩分成了两类,第一类:δ34S>25.00‰,主要为卫城地...  相似文献   
139.
140.
谭耀华  王长委 《测绘通报》2019,(5):113-115,154
为了满足城市森林资源精细化管理的需求,需要不断拓展国产高分辨率遥感卫星数据的应用范围。本文对国产高分辨率遥感卫星数据进行真实性检验并分析其数据特性,在此基础上开展基于国产高分辨率遥感卫星数据的城市森林资源监测的应用研究,并开发了相应的软件系统,对实现城市森林资源的自动化监测具有较高的实用价值和研究意义。  相似文献   
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