华北克拉通中西部岩石圈结构研究

发布时间：2018-05-01 15:16

本文选题：接收函数 + CCP叠加　；参考：《地球物理学进展》2017年04期

【摘要】：本文选择华北中、西部两条宽频带密集流动地震台阵NCISP7和PKU作为研究对象,对南北向A-A"(NCISP7)剖面64个地震台站和东西向B-B"(PKU)剖面50个地震台站记录的远震记录提取P波和S波接收函数,然后通过共转换点叠加(CCP叠加)和偏移成像,得到了华北克拉通中西部岩石圈的精细结构.结果表明,华北克拉通西部地壳较厚,约44 km,莫霍面(Moho)起伏十分平缓,克拉通中部地壳厚度介于36~42 km,表现为西部厚,东部薄,北部厚,南部薄的特点.华北克拉通西部岩石圈厚度100~130 km,克拉通中部岩石圈厚度100~150 km与克拉通东部60~100 km普遍减薄的岩石圈相比,克拉通中西部岩石圈较厚;但与古老稳定克拉通200 km厚度的岩石圈相比,中西部华北克拉通显然也发生了岩石圈减薄现象.无论是在A-A"剖面南北方向上,还是B-B"剖面东西方向上,岩石圈厚度都存在急剧变化,岩石圈结构表现为显著的横向不均匀性.
[Abstract]:In this paper, two wide-band dense mobile seismic array NCISP7 and PKU in the middle and western North China are selected as the research object. The receiver functions of P and S waves are extracted from the remote records of the 64 seismic stations of the north and the north to the A-A "(NCISP7) section and the East West B-B" (PKU) section of 50 seismic stations, and then the co transition points superposition (CCP superposition) and migration imaging are then used. The fine structure of the lithosphere in the central and western North China Craton was obtained. The results showed that the crust of the North China Craton was thicker, about 44 km, and Moho (Moho) undulating very gently. The thickness of the crustal crust in the middle of the craton was between 36~42 km and the west is thick, the East is thin, the north is thick, and the south is thin. The thickness of the lithosphere in the western North China Craton is 100~130 km, G Compared with the lithosphere that is generally thinner in the eastern craton, the lithosphere of the lithosphere is 100~150 km in the middle of the middle of the craton, the lithosphere is thicker in the Midwest of the craton. But compared with the ancient stable craton 200 km thickness lithosphere, the north and central North and Western craton of the central and Western China obviously also has the lithosphere thinning. No matter in the A-A "the north and south direction, or the B-B" In the eastern and Western directions, the thickness of the lithosphere varies dramatically, and the lithospheric structure shows significant lateral heterogeneity.

【作者单位】：中国科学院地质与地球物理研究所;中国科学院大学;地球与空间科学学院北京大学;
【基金】：国家自然科学基金(41125015,41225016,41474040)资助
【分类号】：P315

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