煤田地震勘探转换波观测系统设计与评价

为了更好地开展煤田转换波地震勘探数据采集工作，提出了纵横波联合勘探观测系统设计思路，基于双聚焦理论，计算出分辨率函数、角度与射线参数函数（AVP）、优度和采集痕迹等。结合神东矿区大柳塔煤矿地质条件和地质任务要求，设计了转换波观测系统，采用基于双聚焦理论的定量分析法和常规面元属性分析法对所设计的观测系统进行了评价。结果表明：研究区分辨率函数具有窄而高的主瓣和小的旁瓣，主瓣强度分布均匀；AVP函数在期望的空间带宽内保持平坦，且全区分布均匀；优度值高，采集脚印迹弱，覆盖次数、偏移距和方位角分布均匀，说明所设计的转换波观测系统对研究区开展煤层地质构造和进行岩性解释有利。利用所设计的观测系统进行了实际数据采集，所获得的地震单炮记录信噪比高，反射波组特征清楚，主要目的煤层有明显显示，表明所设计的观测系统适用于研究区转换波勘探，能满足构造勘探和岩性勘探的地质要求。

Design and evaluation of converted wave acquisition geometry for coalfield seismic exploration

To better carry out coalfield converted wave seismic exploration data acquisition work，design idea of seismic acquisition geometry using P wave and P-SV wave joint exploration was proposed，which was based on double focusing theory，calculates resolution function，angle versus ray-parameter(AVP) function，goodness as well as footprint，etc.，Integrating with the geologic setting and the geological task of Daliuta coal mine in Shendong mining area，specific design parameters were proposed，acquisition geometry was designed and evaluated respectively by using multi-parameter quantitative analysis and common bin attribute analysis methods based on double focusing theory.The results show that the resolution function has narrow and high main lobe as well as small side lobe，amplitude of main lobe is distributed uniformly，AVP function remains uniform within the expected space bandwidth，and all are distributed uniformly and have high goodness and weak footprint，folds，offsets and azimuths are uniformly distributed within the research area.The actual data acquisition has been carried out using the design acquisition geometry，and the obtained seismic shot records have high signal-to-noise ratio，the reflection wave group characteristics is clearly，the main coal seam has displayed obviously，it shows that the designed acquisition geometry is suitable for the converted wave exploration of the research area，and can satisfy the geological requirements of the structural and lithological interpretation.