CAJ | 학술논문

在塔河油田近地表微测井数据中普遍存在一段频率低、能量强、波形胖的低频段记录，一般出现在高速层顶界附近。那么，这一特殊的低频段是如何产生的，对激发井深的选择又会产生什么样的影响，是该地区地震采集时不得不面临的重要问题。以往认为该低频段是由岩性变化引起，并且在井深设计方面是选择避开低频段。笔者通过实际资料、理论分析、井深试验的结果分析，认为该低频段是由虚反射引起，在低频段中激发并不改变单炮质量；并对低频段的表现特征、产生机理及对激发井深选择的影响进行了详细的分析，在激发井深设计中可以不考虑低频段的影响。
재탑하유전근지표미측정수거중보편존재일단빈솔저、능량강、파형반적저빈단기록，일반출현재고속층정계부근。나요，저일특수적저빈단시여하산생적，대격발정심적선택우회산생십요양적영향，시해지구지진채집시불득불면림적중요문제。이왕인위해저빈단시유암성변화인기，병차재정심설계방면시선택피개저빈단。필자통과실제자료、이론분석、정심시험적결과분석，인위해저빈단시유허반사인기，재저빈단중격발병불개변단포질량；병대저빈단적표현특정、산생궤리급대격발정심선택적영향진행료상세적분석，재격발정심설계중가이불고필저빈단적영향。
There generally exists the record of a low-frequency band characterized by low frequency,strong energy and fat wave form in the near-surface micro-logging data of the Tahe oilfield,which usually occurs near the top of the high-velocity layer. The reason for the formation of this special low-frequency band and its influence on the selection of IP well depth are important problems that geologists have to face in seismic data acquisition in this area. The low-frequency band was previously considered to be produced by lithological change,and hence in well depth design,the low-frequency band was intentionally avoided.Based on practical data,theroretical analysis and well depth test,the authors hold that the low-frequency band results from ghosting,and that the IP in the low-frequency band will not change the single gun quality.The characteristics and the formation mechanism of the low-frequency band as well as its impact on the selection of IP well depth are analyzed in detail,and it is considered that the influence of the low-frequency band can be ignored in the IP well depth design.