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131.
塔河油田下奥陶统碳酸盐岩储层对比及储层剖面模型 总被引:5,自引:2,他引:5
塔河油田奥陶系储层为岩溶缝洞型的碳酸盐岩储层,缝洞储层的形成与古岩溶作用密切相关,风化壳期岩溶作用对储集空间的发育程度有明显的控制作用。不同的储集空间类型受控于不同的岩溶古地貌单元。裂缝性储层主要分布于风化壳型岩溶不发育地区,或褶皱和断裂构造较发育的变化强烈部位;裂缝-孔洞型储层的分布与古岩溶发育带和岩溶斜坡地区密切相关;裂缝-溶洞型储层其分布与裂缝及古岩溶发育带密切相关,常常是在古岩溶高地边缘或部分岩溶斜坡区,多位于多组构造线的交汇处及褶皱的轴部等。为进一步探讨研究区缝洞型碳酸盐岩储层的空间展布规律,根据暴露区淡水岩溶作用发育特点,依据碳酸盐岩储层的波阻抗响应特征、测井曲线、测试成果及开发动态资料,在恢复古岩溶地貌的基础上,对塔河油田(6区)的岩溶值得层进行了划分与对比。研究结果显示高产井多位于古岩溶地貌相对较高部位,而产量较少或没有出油气的井,则位于岩溶地貌相对较低部位。表明早期的古地貌形态对奥陶系碳酸盐岩溶蚀孔洞的发育具有明显的控制作用。岩溶储层的垂向发育和分布主要受碳酸盐岩古岩溶风化壳垂向分带性的影响,纵向上由风化壳顶面向下储层发育逐渐变差。以奥陶系古风化壳顶面为界,向下每60m为单位,对深度0-60m、60-120m、120-180m、180-240m岩溶储层的纵横向分布特征进行了分析,并建立了相应的储层剖面结构模型。 相似文献
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133.
对1966~1984年邢台地震目录进行了整理,应用基于MATLAB的Z-MAP软件分析了地震目录的完整性,将目录划分为地震活跃时段、地震活动过渡时段、地震活动相对稳定时段。主要分析了各时段地震深度b值、沿断层深度剖面扫描b值,根据深度b值变化对邢台地震演化特点进行了分析。 相似文献
134.
Field measurement and scaled-down wind-tunnel model measurement of airflow field over a barchan dune
Airflow is measured over a barchan dune in the field and over a scaled-down model in a wind tunnel. The change of the flow speed over the stoss side is represented by the change of speed-up ratio. According to the field measurement, the wind profiles within 0-3m above the stoss can be divided into two segments. The lower segment, about 0.66 m thick, is the inner-boundary layer, within which the friction velocities derived from the wind profiles increase from the upwind inter-dune region to the upper stoss, and then decrease near the dune top. This change, together with the changes of airflow field, speed-up ratio and sand flux, is related to the morphological change and contributes to the stable shape and height of a barchan dune. In the wind tunnel, airflow varies in a similar way as in the field, with the speed-up ratios constantly higher than 1.0 and increasing along the stoss slope. While the segmentation of wind profiles also occurs in the wind tunnel, friction velocities derived from the wind profiles decrease along the stoss, indicating a very thin inner-boundary layer above the wind tunnel model where the detailed wind-speed change becomes difficult to measure using the present instruments. 相似文献
135.
JIANGDong WANGNai-bin YANGXIao-huan WANGJi-hua 《中国地理科学(英文版)》2003,13(1):62-65
Daily and ten-day Normalized Difference Vegetation Index(NDVI) of crops were retrieved from meteorological statellite NOAA AVHRR images ,The temporal variations of the NDVI were analyzed during the whole growing season,and thus the principle of the interaction between NDIV profile and the growing status of crops was discussed,As a case in point,the relationship between integral NDVI and winter wheat yield of Henan Province in 1999 had been analyzed.By putting integral NDVI values of 60 sample counties into the winter wheat yield-integral NDVI coordination,scattering map was plotted. It demonstrated that integral NDVI had a close relation with winter wheat yield.These relation could be described with linear,cubic polynomial ,and exponential regression,and the cubic polynomial regression was the best way,In general ,NDVI reflects growing status of green vegetation ,so crop monitoring and crop yield estimation could be realized by using remote sensing technique on the basis of time serial NDVI data together with agriculture calendars. 相似文献
136.
A theoretical model for wind‐sand flow is developed by considering the coupling between wind flow and sand particle motion, the latter subject to the Magnus effect, under different atmospheric stability conditions. Using this model, the characteristics of the wind‐sand flow are discussed in detail. The results show that the atmospheric stability and the Magnus effect both have a strong influence on wind profiles and on the trajectories of sand particles. This approach produces results with characteristics that differ from those previously reported; the latter only applying to atmospheric conditions of neutral stability. The saltating sand reaches a greater height under non‐neutral stability than under neutral stability, while the maximum horizontal distance is greater under unstable conditions and is smaller under stable conditions than under conditions of neutral stability. 相似文献
137.
采用“三小三高二绝招”的工作方法,通过静校正、多域多方法联合噪音衰减和精细的速度分析获得较高分辨率的地震时间剖面,揭示苏码头断裂的展布位置、构造形态及变形样式等。结果表明,区域构造以冲起式为主,在反冲断层与逆冲断层之间形成冲起构造或逆冲三角构造,在地震剖面上有明显的楔状特征。通过地震测线的断层走向以NE为主,倾向以SE为主,部分断层倾向为NW。 相似文献
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139.
The physical retrieval algorithm of atmospheric temperature and moisture distribution from the Atmospheric InfraRed Sounder (AIRS) radiances is presented. The retrieval algorithm is applied to AIRS clear-sky radiance measurements. The algorithm employs a statistical retrieval followed by a subsequent nonlinear physical retrieval. The regression coefficients for the statistical retrieval are derived from a dataset of global radiosonde observations (RAOBs) comprising atmospheric temperature, moisture, and ozone profiles. Evaluation of the retrieved profiles is performed by a comparison with RAOBs from the Atmospheric Radiation Measurement (ARM) Program Cloud And Radiation Testbed (CART) in Oklahoma, U. S. A.. Comparisons show that the physically-based AIRS retrievals agree with the RAOBs from the ARM CART site with a Root Mean Square Error (RMSE) of 1K on average for temperature profiles above 850 hPa, and approximately 10% on average for relative humidity profiles. With its improved spectral resolution, AIRS depicts more detailed structure than the current Geostationary Operational Environmental Satellite (GOES) sounder when comparing AIRS sounding retrievals with the operational GOES sounding products. 相似文献
140.