A novel method for detecting abrupt dynamic change based on the changing Hurst exponent of spatial images     

Wen-Ping He  Qun-Qun Liu  Bin Gu  Shan-Shan Zhao 《Climate Dynamics》2016,47(7-8):2561-2571

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A study of internal solitary waves observed on the continental shelf in the northwestern South China Sea   总被引：3，自引：1，他引：2  

XU Zhenhu  YIN Baoshu  HOU Yijun  FAN Zhisong  Antony K LIU 《海洋学报(英文版)》2010,29(3):18-25

Based on in-situ time series data from the acoustic Doppler current profiler (ADCP) and thermistor chain in Wenchang area, a sequence of internal solitary wave (ISW) packets was observed in September 2005, propagating northwest on the continental shelf of the northwestern South China Sea (SCS). Corresponding to different stratification of the water column and tidal condition, both elevation and depression ISWs were observed at the same mooring location with amplitude of 35 m and 25 m respectively in different days. Regular arrival of the remarkable ISW packets at approximately the diurnal tidal period and the dominance of diurnal internal waves in the study area, strongly suggest that the main energy source of the waves is the diurnal tide. Notice that the wave packets were all riding on the troughs and shoulders of the internal tides, they were probably generated locally from the shelf break by the evolution of the internal tides due to nonlinear and dispersive effects.  相似文献   

基于光谱复原的NMF遥感图像融合改进算法          下载免费PDF全文

马一薇  冯伍法  祝鹏飞  张斌 《海洋测绘》2010,30(1):41-43

在研究了非负矩阵分解(NMF)用于遥感图像融合技术的基础上,改进了一种基于光谱复原的NMF遥感图像融合算法,首先利用矩阵非负性分解求取图像的基向量矩阵,然后综合考虑图像融合后的光谱特性和波形变化情况,对基向量矩阵进行直方图规则化处理,最后得到融合后的图像。实验结果表明,该方法具有较好保持原始图像的光谱信息和空间信息的优点。  相似文献   

一种嵌入式空间数据引擎的设计与实现     

张韵  曹晓航  徐晋晖 《测绘科学》2010,35(4):187-189

空间数据引擎是实现高效空间数据访问和管理的关键技术之一。本文提出一种基于内存映射文件和改进堆组织表方式的嵌入式空间数据引擎设计与实现方法,分析了该数据引擎的组成部分和关键算法,并在其基础上讨论了日志及事务的实现方法。通过对实际数据的实验对比,其结果表明:基于本文方法开发的系统和目前主流嵌入式数据库相比,具有数据访问速度快,占用内存少的特点,适合于空间数据的编辑环境。  相似文献   

Multiple overpressure systems and their relationship with hydrocarbon accumulation in the Qikou Depression of the Bohai Bay Basin,China     

Xue‐Bin Du  Xi‐Nong Xie  Yong‐Chao Lu  Liang Zhang  Wei Peng  Yun‐Peng Li 《Geological Journal》2015,50(4):465-476

Pressure measurements using drill stem tests and estimates from log data calculation indicate that three vertically stacked regional pressure compartments exist in the Qikou Depression of Bohai Bay Basin, N. China. The compartments comprise hydrostatic, upper weak, and lower overpressure systems. Laterally, overpressure (pressure coefficient > 1.2) occurs in the deeper areas and weakens gradually from the centre to the margin of the depression. The accumulation of oil and gas exhibits the interesting characteristics of oil‐bearing layers above gas‐bearing layers in the Qikou Depression. The pattern can be accounted for by the evolution of overpressure system, the maturity process of the source rock and the main fault activity. In the late Dongying Formation (Ed, 30 Ma), the lower overpressure system began to form shape, and the hydrocarbon sources generated a large volume of oil. However, because there was no migration pathway, the oil only accumulated in the original strata. In the late Guantao Formation (Ng, 12 Ma), the gas was generated, the upper overpressure system formed gradually, and the activity of the main fault gradually increased. Then, the overpressure pushed the early gathered oil to flow from the lower overpressure system into the upper overpressure system. Afterwards, the activity of the main fault decreased again and remains weak until now. Thus, later generated natural gas cannot keep migrating along the main fault and can only accumulate in the lower overpressure system. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

鄂尔多斯盆地中北部重力场及基底特征分析     

徐梦龙  杨亚斌  邓友茂  苏振宁  冯楚豪  施苏利 《地质论评》2024,70(S1):125-126

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西太平洋维嘉海山埋藏型富钴结壳生长速率初步研究     

赵斌  何高文  马维林 《地质论评》2024,70(S1):101-103

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川滇黔相邻区沉积型稀土富集规律与成因研究     

田恩源  肖斌  龚大兴 《地质论评》2024,70(S1):260-260

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沙南凹陷古近系中深层砂岩储层特征与岩性油气藏勘探          下载免费PDF全文

胡贺伟  许鹏  于海波  连豪杰  姬新元  丁熠然  邵龙义 《地质论评》2024,70(1):2024010018-2024010018

渤海湾盆地沙南凹陷陡坡带古近系沙河街组二段发育辫状河三角洲相砂岩储集层,该储层受构造位置、埋藏速率、古地温变化、断裂作用的影响,在不同构造区特别是中深层,其物性具有明显的差异性。笔者等利用钻井、测井、地震及分析化验等资料,对中深层砂岩储层沉积相、成岩作用及孔隙演化特征进行研究,提出优质储层的主控因素及演化规律。结果表明,研究区中深层砂岩以岩屑长石砂岩为主,孔隙以粒间溶孔、粒内溶孔为主,储层存在中孔中渗型、中孔低渗型、低孔低渗型和低孔特低渗型4类,且以中孔低渗型为主。储层孔隙总体比较发育,储层整体表现为中等孔隙度、中等渗透率,储层物性较好。对区内优质储层发育的控制因素进行研究表明,富含石英、长石的物源区母岩是区内优质储层发育的物质基础,三角洲分流河道沉积相是优质储层发育的主要沉积相类型,成岩晚期方解石胶结物经过强溶蚀作用是优质储层发育的关键因素。对中深层优质储层时空演化规律分析表明,沙南凹陷南次洼曹妃甸14- e构造区发育辫状河三角洲相砂体,且这些砂体都位于有效烃源岩内,油气运聚条件优越,所以岩性油气藏勘潜力较大。已钻井也证明了区内厚油层的存在,说明该区是沙南凹陷岩性油气藏勘探最有利场所。  相似文献   

基于A- CGAN的深反射地震数据随机噪声压制方法研究          下载免费PDF全文

韩建光  王卿  许媛  刘志伟 《地质论评》2024,70(1):228-238

基于深度学习的地震数据噪声压制方法是当前地震数据去噪处理的重要方向。深度学习方法突破了传统滤波处理的局限,在对常规地震数据的噪声压制中表现出效率高、信噪分离效果好的特点。但针对深部弱有效反射数据,当前的深度学习方法特征提取能力有限,难以取得较好的去噪效果。笔者等结合深反射地震数据特点,针对当前深度学习噪声压制方法在特征提取及对数据集依赖上的局限,提出了基于注意力循环生成对抗网络(Attention Cycle- Consistent Generative Adversarial Networks,A- CGAN)的深反射地震数据随机噪声压制方法。借助循环一致生成对抗网络(Cycle- Consistent Generative Adversarial Networks,Cycle- GAN)的域映射思想,降低对数据集的要求。为了构建适用于深反射地震数据的去噪网络,从3个方面对Cycle- GAN进行改进：在Cycle- GAN的生成器（去噪器）中加入残差结构和注意力机制,用于加深网络深度和提高其特征提取能力;在Cycle- GAN的鉴别器中使用块判决,提高鉴别精度和准确度;在损失函数部分加入感知一致性损失函数,提升网络模型恢复纹理细节信息的能力。通过合成地震数据和实际深反射地震数据测试,验证了优化算法的有效性,体现了良好的应用价值。  相似文献