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171.
南堡凹陷潜山是油田近年来勘探开发、增储上产的重点区域,但其储层横向变化快、类型多、流体复杂的特征,为提高油气勘探成功率,开展了针对碳酸盐岩叠前、叠后流体检测的综合研究,形成一套实用性强的流体检测技术系列.在高保真的逆时偏移数据体和叠前CRP道集的基础上,运用叠前AVO分析、衰减梯度属性、低频能量属性以及多属性综合分析技术在南堡凹陷潜山开展流体检测,在此基础上,优选有利储层发育区,部署探井,取得较好的勘探效果,证实该技术系列的准确、可靠、实用性. 相似文献
172.
Geospatial-temporal analysis of land-use changes in the Yellow River Delta during the last 40 years 总被引:5,自引:0,他引:5
Qinghua?YeEmail author Gaohuan?Liu Guoliang?Tian Shenliang?Chen Chong?Huang Shupeng?Chen Qingshen?Liu Jun?Chang Yanan?Shi 《中国科学D辑(英文版)》2004,47(11):1008-1024
Research on land use/land cover changes (LUCC)has been the core project of the Global EnvironmentalChanges since the 1990s[1—6]. Scientists at home andabroad have been laying emphasis on integrationstudies on land-use change by “space and process”features[7—10] as researches on LUCC are in a greatdeal. It is of paramount important for us to studyLUCC at various spatial-temporal scales and build aquantitative assessment of land-use conversion by in-tegrated spatial-temporal features. … 相似文献
173.
To investigate whether the biological toxicity of aquatic hypercapnia is due to the direct effects of CO2 or to the effects of acidification of seawater by CO2, the Japanese flounder (Paralichthys olivaceus) was subjected to seawater equilibrated with a gas mixture of air containing 5% CO2 (pH 6.18) or seawater acidified to the same pH with 1 N H2SO4. All the fish died within 72 h in the CO2 exposure group, whereas no mortality occurred in the acid group. Acid-base parameters as well as plasma ion concentrations were severely perturbed in the CO2 exposure group, whereas they were minimally affected in the acid group. These results clearly demonstrate that the mortality in the CO2 group is a direct result of the elevated levels of dissolved CO2 and not to the effects of the reduced water pH. 相似文献
174.
175.
Lian-Teng Song Zhong-Hua Liu Can-Can Zhou Jun Yu Li-Jun Xiu Zhong-Chun Sun Hai-Tao Zhang 《应用地球物理》2017,14(1):10-20
Tight sandstone has a certain anisotropy. Using ultrasonic measurements of samples in three different directions and related matched experiments, this study systematically analyzes the pore structure and anisotropy of tight sandstone samples obtained from oil fields and compares results with those of shale. Results firstly show that the anisotropy of tight sandstone is mainly related to the compositional layering and thin interbedding which occur in different sedimentary environments. Tight sandstone has typical transverse isotropic medium characteristics, Young’s modulus increases in different directions with increasing confining pressure, Poisson’s ratio change is not obvious, anisotropic coefficients decrease with increasing effective pressure, and a certain linear relationship exists between ε, γ, and δ. This article finally summarizes anisotropy in different areas, thereby providing a foundation for the use of suitable appraisal models in different regions. This research can be used as an experimental reference for logging evaluation, seismic data interpretation, and fracturing develop of tight sandstones. 相似文献
176.
Jun Guo Jianzhong Zhou Lixiang Song Qiang Zou Xiaofan Zeng 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(4):985-1004
Assessment of parameter and predictive uncertainty of hydrologic models is an essential part in the field of hydrology. However, during the past decades, research related to hydrologic model uncertainty is mostly done with conceptual models. As is accepted that uncertainty in model predictions arises from measurement errors associated with the system input and output, from model structural errors and from problems with parameter estimation. Unfortunately, non-conceptual models, such as black-box models, also suffer from these problems. In this paper, we take the artificial neural network (ANN) rainfall-runoff model as an example, and the Shuffled Complex Evolution Metropolis algorithm (SCEM-UA) is employed to analysis the parameter and predictive uncertainty of this model. Furthermore, based on the results of uncertainty assessment, we finally arrive at a simpler incomplete-connection artificial neural network (ICANN) model as well as with better performance compared to original ANN rainfall-runoff model. These results not only indicate that SCEM-UA can be a useful tool for uncertainty analysis of ANN model, but also prove that uncertainty does exist in ANN rainfall-runoff model. Additionally, in some way, it presents that the ICANN model is with smaller uncertainty than the original ANN model. 相似文献
177.
Vertical profiles of fluid velocity and suspended sediment concentration in nearshore 总被引:2,自引:0,他引:2
Based on the power function of velocity and the friction velocity,a velocity profile is obtained.By solving the Schmidt’s diffusion equation,an equilibrium suspended sediment concentration profile is further deduced.The profiles of velocity and suspended sediment concentration agree well with the field data,and the profile of suspended sediment concentration avoids the unreasonableness of the classical Rouse profile such as a zero value at the water surface.According to these profiles,an expression which is easy to use for calculating the suspended sediment transport rate is derived. 相似文献
178.
179.
基于《中国震例》记录的1966年以来的震例, 按异常测项和变化类型分类统计了与地下流体相关的异常数量与震级、 震中距、 持续时间的相关性。 结果显示: 中国大陆M6.5以下地震的地下流体异常数量与震级无相关性, M6.5以上地震异常数量随震级的增大而增多, 二者呈指数关系; 地下流体异常多集中于距震中300 km范围内, 且各测项间无明显区别, 异常数量与震中距之间呈Gamma分布特征; 地下流体异常时空演化主要表现为 “向震中收缩”、 “构造控制”和“相对集中”三种典型特征, 震前异常数量主要表现为“持续增长”型和“先增后减”型两类, 且以“先增后减”型居多。 本文统计得到的地下流体前兆信息特征, 可为今后地震预报实践提供一定参考。 相似文献
180.