Study On Seismic Data Acquisition Method Of Active Faults At Yanqing Area

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.