• ISSN 2097-1893
    • CN 10-1855/P

    中国大陆岩石圈结构研究综述

    A review on lithospheric structures of Chinese mainland

    • 摘要: 中国大陆是在漫长地质历史时期,经过多个块体拼合形成的,不同块体的岩石圈结构差异明显,岩石圈块体之间相互作用强烈,形成了现今中国大陆地质构造活跃、地质灾害严重的基本特征. 21世纪以来地震学发展迅速,揭示了高精度的地壳和上地幔结构,本文总结了地震学获得的中国大陆莫霍面和岩石圈-软流圈边界深度的新进展,构建了一级尺度中国大陆岩石圈的基本框架. 总体上,青藏高原地壳最厚,可达70 km;中国东部地壳最薄,平均30 km左右. 但在小尺度结构上,还有进一步提升的空间:一方面,天然地震比人工地震获得的地壳厚度整体偏小,可能反映了复杂的莫霍面性质;另一方面,主要构造边界或断裂带附近地壳结构横向变化剧烈,需要在关键地区开展密集地震台阵观测与研究,从而更好地研究块体的相互作用. 岩石圈厚度的研究相对偏少,仅在若干剖面上获得了可靠结果,且与地震波速度结构和热岩石圈结构还存在明显差异,未来需要在数据和方法上进一步努力. 在一维岩石圈圈层结构的基础上,未来需要进一步揭示高精度的三维岩石圈结构,以便更好地约束中国大陆岩石圈的流变性质与变形特征,进而探讨与中国大陆地球动力学演化相关的重要科学问题.

       

      Abstract: The formation of the Chinese mainland has been a result of the amalgamation of multiple blocks over an extended geological history. The lithospheric structures of these different blocks exhibit significant variations, and their interactions have been intense, leading to the fundamental characteristics of active geological tectonics and severe geological hazards in present-day China. Since the beginning of 21st century, seismology has developed rapidly, revealing high-precision crustal and upper mantle structures. This paper summarizes the latest progress in seismological studies regarding the depths of the Moho and the lithosphere-asthenosphere boundary (LAB) in the Chinese mainland, constructing a fundamental framework for the lithosphere at a first-order scale. Overall, the crust of the Qinghai-Xizang Plateau is the thickest, reaching up to more than 70 km, while the crust in eastern China is the thinnest, averaging around 30 km. However, improvement is necessary particularly in understanding small-scale structures. On one hand, the crustal thickness derived from natural earthquakes is generally smaller than that obtained from artificial seismic sources, which may reflect the complex nature of the Moho. On the other hand, the lateral variations in crustal structure near major tectonic boundaries or fault zones are significant, arguing for dense seismic array observations and research in key areas to better study block interactions. Research on lithospheric thickness remains relatively limited, with reliable results obtained only along certain profiles, and there are notable discrepancies between seismic wave velocity structures and thermal lithospheric structures. Future efforts are required in both data acquisition and methodological advancements. Building on one-dimensional lithospheric layer structures, future research should focus on revealing high-precision three-dimensional lithospheric structures to better constrain the rheological properties and deformation characteristics of the Chinese mainland lithosphere. This will facilitate the exploration of important scientific issues related to the geodynamic evolution of the Chinese mainland.

       

    /

    返回文章
    返回