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分析了由Kyrgyzstan宽带台网(KNET)记录的P-SV转换震相来研究天山中部和哈萨克地盾下方上地幔中的相变特征。在几个山脉前沿台站的记录中,来自天山下方410km间断面的P-SV震相比来自哈萨克地盾的早2s。因为哈萨克地盾台站的时间延迟是正常的,而且天山这一部位下方上地幔地震波的速度明显地低(大约比哈萨克地盾北边低4％),来自410km的较早转换波波至表明了这些间断面被抬升了大约20m。410km的间断面被抬升是由于冷物质的侵入。我们的结果与以下的模型相一致:这个地区岩石层在碰撞期间形成的根后来被拆离并且现在驻留在约410km的深度。
The P-SV transition phases recorded by the Kyrgyzstan Broadband Network (KNET) were analyzed to study the phase transitions in the upper mantle beneath the Tianshan Mountains and the Kazakhstan Earthquake. In the records of several mountain front stations, the P-SV shock from the 410 km section below Tianshan is 2 s earlier than that from the Kazakh shield. Because the time delay of the Kazakhstan shield station is normal and the velocity of the upper mantle seismic waves beneath this part of the Tianshan is significantly lower (about 4% lower than the northern part of the Kazakh shield), the earlier converted wave from 410 km indicates These discontinuities were raised about 20m. The 410km section is uplifted due to the intrusion of cold matter. Our results are consistent with the model that the roots formed by the rock layers in this area during the collision are later detached and now reside at a depth of about 410 km.