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针对塔里木盆地库车坳陷地表和地下构造复杂、地震记录波场杂乱、资料信噪比低的问题,通常采用减小道距与炮距、增加接收道数来提高覆盖次数,但由于激发和接收条件难以改善,同时干扰波难以有效地压制和削弱,即使成倍地提高覆盖次数,二维地震采集对剖面品质也无明显改善。通过对该区地震地质条件分析,在查明地震信号信噪比低的原因基础上,提出了在观测系统设计时采用宽线采集技术,在野外施工中采用准确的近地表模型技术、分区埋置改善检波器接收条件技术、激发药量选取技术、控制环境噪音技术等方案。现场采集试验表明:与单线同区老资料对比,首次获得了较好的深层中生界地震反射,新生界的地层反射资料有明显改善,构造面貌更加清楚、构造高点断层分布情况更加可靠。
In view of the complex surface and subsurface structures in the Kuqa Depression of Tarim Basin, the seismic wavefields are cluttered and the signal-to-noise ratio is low, the number of coverage and the number of receiving channels are usually reduced by reducing the track spacing and the gun spacing. However, The receiving condition is hard to be improved, and the interference wave can not be effectively suppressed and weakened. Even if the coverage times are doubled, the 2D seismic acquisition has no significant improvement on the profile quality. Based on the analysis of the seismic geological conditions in this area, based on the reason of low signal-to-noise ratio of the seismic signal, the paper proposed a wide-line acquisition technology in the design of the observation system, an accurate near-surface model technology in the field construction, Set to improve the receiving conditions of the detector technology, to stimulate drug selection technology, control of environmental noise and other programs. The field experiment shows that compared with the single line and the old data, the seismic reflection of the deep Mesozoic is obtained for the first time. The information of the formation reflection in the Cenozoic has obviously improved. The tectonic features become clearer and the distribution of faults at the structural high point is more reliable.