本文利用北京大学宽频带流动地震台阵和新疆地震监测台网12个月连续地震记录数据,采用环境噪声层析成像方法获得了新疆地区的周期从10～35 s范围内的瑞利面波相速度异常分布图像.研究结果与地表地质构造相一致,新疆地区的天山、两盆大地构造与瑞利面波相速度异常有较好的对应关系.短周期10～20 s的图像显示两个盆地内都呈现低速异常,对应盆地较厚的沉积层.中长周期25～35 s的层析成像结果显示东西天山地区存在明显异常差异.本文获得的新疆地区地壳和上地幔相速度结果,也为进一步结合传统天然地震面波成像方法,最终获得新疆地区的三维剪切波速度结构奠定基础.%Using continuous data from Peking University Yutian broadband seismic array and Xinjiang seismic monitoring network, we have obtained phase velocity maps of Rayleigh wave in Xinjiang area between periods 10~35 s from ambient noise. The results correlate well with the surface geological features, such as the Tien Shan, Tarim Basin and Junggar Basin are well depicted by the Rayleigh wave phase velocity anomalies. The phase velocity maps at 10 ~ 20 s show comparatively low velocity anomalies in Tarim Basin and Junggar Basin, corresponding to the thick sediments. From intermediate periods to long periods, 25~35 s, the phase velocity maps manifest clear differences in the Eastern and Western Tien Shan area. We obtained the crust and upper mantle Rayleigh phase velocity maps of Xinjiang area. By combining the traditional surface wave methods, this research would be a good foundation to reveal the 3D shear wave structure of this area.
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