摘要
It is difficult to acquire high-quality seismic sections in Qiangtang basin because of its complex seismic geological condition and low signal-noise ratio.In order to find out suitable technique for this basin,the authors conducted tests along a seismic profile more than several hundred kilometers long on the basis of increasing signal-noise ratio.The results indicate that a single hole with the depth of at least 18 meters,16~20 kilogram charge sizes,20~40 meters trace group interval,more than 120 folds and "X" type geophone array map constitute the optimum shooting and receiving parameters suitable for the feature of Qiangtang basin.And the quality of 2D seismic profiles obtained by using these parameters and techniques can be increased greatly and is obviously superior to that of the profiles obtained in the past.The processed stacking profiles show informative reflection and reveal the features of spatial distribution of Palaeozoic basement,Triassic,middle-upper Jurassic,upper Jurassic strata and faults,thus providing high-quality data for ascertaining the layer thickness and the structural traps and boundaries.In addition,the processed stacking profile across the central uplifting belt clearly shows that this uplifting belt is an anticline structure formed recently instead of an ancient dome.