新疆准噶尔盆地乌伦古地区地震采集方法

On Seismic Acquisition Technique in Wulungu Region of Xinjiang Junggar Basin

乌伦古地区地表为戈壁砾石和沙漠区,低降速带厚度大,地下构造复杂,以往地震资料品质较差,单炮记录信噪比低,剖面效果不理想。在试验资料分析的基础上,研究大吨位可控震源在该区的激发效果,结合观测系统设计优化方法发现构造复杂地区采用针对性的观测系统设计方法可取得较好效果,采用多台震源联合激发,可提高激发能量,获得较高信噪比单炮记录。

Wulungu is located in desert region with Gobi gravel where there is a thicker low velocity layer and complex subsurface structure and where former seismic data are of poor quality, single--shot record has a low signal to noise ratio and profile result is not satisfactory. On the basis of analysis of test data, a study has been made in shooting result in this region by means of large--tonnage vibroseis. In addition, combined with recording geometry design optimization method, it is found out that the adoption of specific design method in the region with complex structure can acquire better result and the adoption of a joint shooting of more than one vibroseis can increase shooting energy and gain single--shot record with higher SNR.