【作者】 韩国胜；

【导师】 钱荣毅；

【作者基本信息】 中国地质大学（北京） ， 地球探测与信息技术， 2011， 硕士

【摘要】 活动断层探测是为减轻地震灾害而开展的一项重要工作。城市活动断层多为隐伏断层,与地震和地质灾害紧密相关,从而对城市和工程安全造成直接威胁,加强城市地区活动断层探测工作可以有效避免损失。近些年来,随着城市建设工程探测精度要求的逐渐增高,以多次覆盖为核心的地震探测方法在城市工程方面已经逐渐体现出了它的优势,采用地震勘探技术进行城市地区活动断层工作也得到了巨大的发展。在延庆新城地区开展地震探测工作具有其特殊性。首先,研究区城市规划范围大,区内地质构造复杂,相对于工程勘察来说,所布设的工作量并不能完成如此大范围内详实的探测;其次,研究区内第四系厚度较大,而活动断层对地表造成的巨大破坏通常是由深部发震构造带动表层的活动,因此在采用高精度探测浅层活动断裂的同时要考虑获取研究区的中、深部资料;再次,城区范围内同时存在多条断层,分布复杂,采用长剖面进行多条断层同步观测。地震测线在城区经过建筑、村庄、公路密集的地段,采集激发、接收条件较差,干扰较大,局部表层地层内含有砂卵石层,因此必要时改变常规的观测方法,来克服场地障碍带来的困难。本文针对研究区的特点,通过对地震探测采集参数优选论证,为研究区内反射地震探测活动断层工作提供参考意见。主要完成了以下工作:1、本文通过对研究区进行野外区域地质调查工作,结合理论分析有针对性地设计出适合研究区特点的采集方法。研究区城市规划范围大、区域地质构造复杂,设计采用主辅线不同道距的线形宽线方法采集,避免解释中断点组合不明问题。利用长排列接收、长剖面布线方式克服厚新生界覆盖、多断层分布的特点,同时采用中间激发,主线小道距非对称接收方式观测,在保证浅层高密度采集的同时获取中、深部各地层的资料;2、完成研究区采集方法试验工作,对试验资料进行对比工作,通过对分析结果总结出适合本研究区的采集方法;3、建立区域内二维地质模型,通过正演模拟对观测方法的各项参数进行论证优选。本文针对延庆地区活动断层探测的探测目标,进行了反射地震观测系统参数选取的研究工作,结合实际地质条件,最终确定了在延庆地区采用线形宽线观测方法,并取得了显著效果,获得了高品质地震资料,为类似地区活动断层探测工作提供参考。更多还原

【Abstract】 Active fault detection is an important work carried out to mitigate earthquake disaster. Urban active fault which related to earthquake and geological disasters are mostly buried fault, and thus a direct threat of the city and building safety, detect active faults in urban areas can avoid the loss. In recent years, with the urban construction projects gradually increased detection accuracy requirements to multiple coverage seismic methods as the core projects in the city have gradually demonstrated the advantages of its high precision, the use of seismic exploration technology for active faults in urban areas Work has also been a huge development.It is particular to carry out seismic surveys in Yanqing areas. Firstly, the study area range urban planning, and the local geological structure is complicated, relative to the engineering survey, It can’t work out for the engineering survey with such a large range of full and accurate detection; secondly, The Quaternary is deeper, The active fault damage to the surface is usually constructed by a deep structure, so detection of active faults should be considered for the shallow and deep with high-precision at the same time, thirdly, There is a number of faults in the city, with complex distribution, using a long profile for seismic surveys is a better way. Seismic line through the buildings in the city, village, road-intensive lots, with a poor reception conditions, and the shallow formation contain sand and pebble bed, so it is necessary to change the conventional observation method, to overcome the difficulties result from obstacles.In this paper, we talk of the characteristics of the study area, through the selection of seismic acquisition parameters Provide some suggestions for the study of active faults inYanqing area. Main completed the following:1. basing on the investigation of regional geologic in the area and theoretical analysis , this paper design the characteristic collection method suitable for the study area. the study area range urban planning, and the local geological structure is complicated, designed a method of wide line with different group interval from the main and auxiliary line,to avoid the problem of interpretation with an unknown breakpoint combinations. There is a long array designed to overcome the thick Cenozoic cover and the distribution of the faults, with the straddle spread and asymmetric receive mode. That is the way to ensure the data of layer with a high-density acquisition;2. the completion of the experiment for acquisition method, compared to the work of experimental data, summarized by the results of the study area for the collection methods;3. we established the 2D model of the region geology, through the method of forward modeling to optimize the parameters.In this paper, carring out the study of seismic observation system parameters Yanqing Active Fault Survey of exploration goals, of the selected research work, combined with the actual geological conditions, finalized in Yanqing district using linear wide-line observation method, and achieved remarkable results, obtained high quality seismic data for detection of active fault in similar areas to provide information.更多还原