中文摘要：

在碎屑岩薄砂体油气储层勘探中,由于目标区选择和井位部署的需要,落实薄砂体的横向展布至关重要。北黄海盆地东部坳陷下白垩统发育扇三角洲沉积相,物源多方向,岩性横向变化大,储层较薄,受地震资料自身频率的限制,利用叠后波阻抗反演方法难以识别薄储层,而基于匹配追踪算法的谱分解技术具有计算速度快、时频分辨率高的特点,是寻找薄砂体储层最为有利的手段。通过分析井点处下白垩统薄砂体的地震响应,再通过地震资料提频处理,高频段能够区分薄储层,然后用匹配追踪算法对地震资料进行频谱分解和地震沉积旋回分析,最后在高频层序地层上对薄砂体储层进行分频解释。结果表明,下白垩统虽为低孔、特低渗储层,但以指状分布的扇三角洲平原砂岩百分含量高,烃类检测效果好,为下白垩统砂岩储集层圈闭的有利区域。

英文摘要：

To meet the needs in selection of target area and well locations for oil and gas exploration of thin classic sand reservoirs, it is very important to disclose the three dimensional distribution of sandbodies. In the Eastern Depression of North Yellow Sea Basin, fan deltaic deposits are well developed in the Cretaceous. The sand deposits usually come from multiple sources, having sharply lateral change in lithology and thin in thickness. Restricted by the frequency of seismic data, the seismic impedance inversion method is difficult to identify the thin reservoir. The matching pursuit spectrum decomposition technique, which has the advantages of fast computing speed and high time-frequency resolution, is found in this case of study the most favorable method for thin sand reservoir identification. In this paper, by analyzing the response of thin sand body of lower Cretaceous to the seismic in the well location, through picking up of the high frequency components after seismic frequency-broadening, which may distinguish the characteristics of the thin reservoir, then we carried out the matching pursuit for 3D seismic data spectral decomposition and seismic sedimentary cycle analysis, and make frequency-division interpretation on the high-frequency sequence stratigraphy. The results show that although the Early Cretaceous sand body is low in both porosity and permeability, the contents of finger-like fan delta plain sanstone is rather high. Hydrocarbon detection based on spectrum analysis proves that it is a favorable area for reservoir traps.