【作者】 王海燕；

【导师】 王彦春； 张新华；

【作者基本信息】 中国地质大学（北京） ， 地质工程， 2009， 硕士

【摘要】 本论文针对研究区的地质特点,确定了以高分辨率三维地震资料为基础,针对低幅度构造、小断层、薄砂层研究采用的相应的技术手段。从以往资料及采集技术难点分析入手,通过对地震地质条件分析、以往施工方法分析、干扰波分析、以往剖面和单炮分析以及采集技术难点分析,详细阐述了研究区深层信噪比和分辨率的影响因素和采集技术难点;通过对大地吸收、激发以及接收方式等采集技术研究,并结合处理方法研究,总结了大地吸收衰减制约着地震分辨率的大幅度提高,进行合理的大地吸收衰减理论计算,可以指导制定合理的采集技术指标;运用运动学和动力学理论进行微测井解释,能够准确地得到表层各项参数,结合表层岩性调查,可以确定最佳激发岩性,保证较好的激发效果,增强中深有效信号能量,并拓展有效频宽;采用多井组合激发,能够增强激发下传能量,较大程度地提高高频信号的信噪比,拓展有效频宽,从而提高中深层的分辨率;采用合适的检波器类型,增强耦合效果,采用合适的串并联连接方式,提高检波器灵敏度,能较好地接收中深层高频弱信号;野外采集时采用宽频档(不加低截)、高前放增益记录,仪器记录弱信号的能力较强(仪器系统动态范围较大),且对弱信号的能量有一定程度的提高等一套适合提高辽河西部凹陷中深层地震资料信噪比和分辨率技术系列。更多还原

【Abstract】 This paper is mainly aiming at work out a technique series for improving the seismic data signal to noise ratio and resolution of middle and deep layer at Western Sag of Liaohe Basin, Northeast China.The paper is also aim at confirming corresponding research techniques and methodologies for low range formation, tiny fault and thin sandy layer based on the study of the geological features and the high resolution 3D seismic data of the research target zone.The paper started from former data and difficulties of acquisition techniques, further to the analysis of seismic geological conditions, former acquisition methodologies, noises, and acquired raw shots and stacks, also expatiate on the factors which affected the signal to noise ratio and resolution of deep layer and difficulties of acquisition techniques. Furthermore, the paper summarize that enhancement of resolution are highly restrained by absorbing of ground via researches on absorbing of ground, methodologies of source and receiver and other acquisition techniques, and along with research on methodologies of processing.So, suitable acquisition parameters could be selected by calculating with rational ground absorbing attenuation theory, every parameter of weathering layer could be acquired exactly by interpreting up-hole with kinematic and mechanical theories, prime lithology for source could be decided, and along with survey of weathering layer, better source result could be ensured, energy of valid signal could be enhanced, and valid frequency range could be expanded. By using pattern hole the sources energy propagation could be boosted, signal to noise ration of high frequency signal could be enhanced greatly, valid frequency range could be expanded, and consequently the resolution of middle and deep layers. By adopting proper geophone could improve coupling, by utilizing right geophone array could enhance its sensitivity to receive weak high frequency signal of middle and deep layers. Recording with wide frequency band (without low cut), high pre-amplification while filed operation could expand capability of recording system for recording weak signal, and enhance weak signal to a certain range.更多还原