薄煤层PP波与PS波AVA地震响应特征  

PP- and PS-wave AVA response characteristics for thin coal seam

作　　者：杨震[1,2] 芦俊[1,2] 孟星浑 王赟[3] 

机构地区：[1]中国地质大学(北京)能源学院,北京100083 [2]中国地质大学(北京)海相储层演化与油气富集机理教育部重点实验室,北京100083 [3]中国地质大学(北京)地球物理与信息技术学院,北京100083

出　　处：《煤炭学报》2015年第6期1435-1441,共7页Journal of China Coal Society

基　　金：国家高技术研究发展计划(863)资助项目(2013AA064201);中央高校基本科研业务费专项资金资助项目(2-9-2013-093);国家自然科学基金资助项目(41104084)

摘　　要：传统的AVA特征分析基于近似Zoeppritz方程,但是近似Zoeppritz方程并不适用于薄层。为获得更准确的薄煤层地震响应特征,建立了薄煤层模型,并采用基于Brekhovskikh方程的薄层反射系数谱理论,模拟薄煤层PP波与PS波的振幅及相位随入射角、入射波主频变化的地震响应;对薄煤层模型的底板采用精确Zoeppritz方程进行了AVA模拟,并与基于薄层反射系数谱理论的AVA响应进行了对比分析。结果表明:薄煤层AVA特征受到各层弹性参数、层厚以及入射波主频等因素的影响,基于薄层的反射系数谱更适用于薄煤层AVA响应特征的分析。The approximate Zoeppritz equation is the basis of traditional AVA analysis,but it is not suitable for the study of thin layers. In order to get more accurate seismic responses of thin coal seam,the authors developed a realistic model of thin seam. According to the theory of thin reflectance spectrum based on Brekhovskikh equation,the thin seam amplitude responses and phase responses were analyzed with varying incidence angle and dominant frequency.Furthermore,the authors simulated the AVA response of the seam floor using the exact Zoeppritz equation and compared with the AVA response which was based on thin reflectance spectrum. The results show that: the AVA response of thin coal seam is affected by elastic parameters of layers,layers thickness,the dominant frequency of the incident wave,and so on,and the theory of thin reflectance spectrum is more suitable for thin coal seam AVA analysis.

关 键 词：薄煤层 AVA PP波 PS波 反射系数谱 

分 类 号：P631.4[天文地球—地质矿产勘探] P618.11[天文地球—地质学]