天然气水合物和游离气饱和度评价方法及其在南海北部的应用

发布时间：2018-01-12 04:36

  本文关键词：天然气水合物和游离气饱和度评价方法及其在南海北部的应用　出处：《海洋地质与第四纪地质》2017年05期 　论文类型：期刊论文

  更多相关文章： 天然气水合物 饱和度 各向同性 各向异性 速度 电阻率

【摘要】：饱和度是评价天然气水合物资源量的重要参数之一,不同海域由于水合物微观赋存状态差异,评价方法不同。大量水合物钻探取心显示在珠江口盆地不同海域发现了不同类型的水合物,在东部海域发现了呈脉状、块状、结核状等裂隙内形成肉眼可视的水合物,而神狐海域发现了呈分散状充填在孔隙空间不同饱和度的水合物,两种不同类型水合物层的测井异常响应特征不同,评价饱和度方法不同。研究表明东部海域基于各向异性电阻率模型估算的水合物饱和度与压力取心吻合,近海底发育的水合物层饱和度相对较低,约为10%,而基于各向同性模型估算水合物饱和度高达60%,远大于压力取心饱和度。在碳酸盐岩层,基于未固结地层各向同性与各向异性估算水合物饱和度大于氯离子异常估算水合物饱和度,而利用胶结模式估算水合物饱和度与氯离子吻合。利用地震资料,以测井为约束利用稀疏脉冲反演地层的速度或波阻抗,结合不同岩石物理模型分析,再通过线性拟合或循环迭代方法可以估算水合物饱和度体,研究水合物的空间分布。通过沿稳定带底界提取水合物饱和度属性,发现神狐海域水合物呈不均匀分布,在局部峡谷脊部呈条带状特征。
[Abstract]:Saturation is one of the important parameters to evaluate the gas hydrate resources. A large number of hydrate drilling coring shows that different types of hydrates have been found in different sea areas of the Pearl River mouth basin, and veins and blocks have been found in the eastern sea area. In the nodule and other fractures, the visible hydrate is formed in the naked eye, while in the Shenhu sea area, the hydrates filled in the pore space with different saturation are found, and the logging abnormal response characteristics of the two different types of hydrate layers are different. The results show that the hydrate saturation estimated by anisotropic resistivity model is consistent with the pressure coring, and the saturation of hydrate layer developed near the sea floor is relatively low (about 10%). Based on the isotropic model, the hydrate saturation is estimated to be as high as 60%, which is much larger than the pressure coring saturation. The estimation of hydrate saturation based on the isotropy and anisotropy of unconsolidated strata is greater than that of chloride ion anomaly, while the cement model is used to estimate hydrate saturation in accordance with chlorine ion. The velocity or wave impedance of formation is inversed by sparse pulse with logging as constraint. Combined with different rock physical models, the hydrate saturation volume can be estimated by linear fitting or cyclic iteration method. By extracting the hydrate saturation properties along the bottom boundary of the stable zone, it is found that the hydrate distribution in Shenhu sea area is uneven, and that in the local canyon ridge, the hydrate is striped.
【作者单位】： 中国科学院海洋研究所海洋地质与环境重点实验室;海洋国家实验室海洋矿产资源评价与探测技术功能实验室;美国地质调查局丹佛能源中心;
【基金】：国家自然科学基金项目(41676041,41676040) 中国地调局南海水合物勘探项目(DD20160211)
【分类号】：P618.13;P744.4
【正文快照】： 3.美国地质调查局丹佛能源中心,丹佛,美国80225)天然气水合物是由水和碳氢气体(主要是甲烷气体)在低温、高压环境下生成的固态化合物。世界不同海域的水合物钻探发现其在自然界中存在的形态多种多样,它既可能均匀充填在沉积物的孔隙空间,也可能呈脉状、块状、层状或结核状等似，

本文编号：1412739