龙口海域煤田地震资料夹矸异常分析

龙口煤矿主要为新生界古近系含煤建造,共含煤1、煤2、煤3、煤4四层煤,煤2为全区稳定可采煤层。以往的地震勘探剖面上反映煤2反射特征明显,断点干脆。在新采集的海上三维地震剖面上,煤2局部存夹矸,致使煤2反射波表现异常。通过正演模拟,总结出夹矸层厚度与频率的相互关系及其反射波特征。从实际资料的处理中,可以看出,经保幅处理后的叠前时间偏移剖面,比常规时间叠加剖面更能准确的反映出夹矸层的透镜体反射特征,特别是透镜体的上、下部同相轴反射波组强弱之分更加明显。实际采掘数据表明,地震剖面解释的夹矸分布范围,与实际情况吻合较好。

Parting Anomaly Analysis of Coalfield Seismic Data in Longkou Maritime Space

The Cenozoic Paleogene System coal-bearing formation contains four coal seams namely Nos.1, 2, 3 and 4, while the No.2 coal is stably mineable in the whole area. Reflection characteristics of No.2 coal are obvious with sound break points on previous seismic sections. On the newly acquired offshore 3D seismic sections, No.2 coal has partings locally, made the reflection wave anomalous. Through forward modeling, has summed up relationship between parting thickness and frequency, as well as reflection wave characteristics. From practical data processing find out, prestack time migration section after amplitude preservation processing can reflect reflection characteristics of parting lenses more correct than traditional time stacked sections, especially, reflection wave set lineups upon and under lenses are clearer according to their degree of strength. The mining practice demonstrated that parting distribution interpreted by seismic sections is tally with the actual situation.