关键词: 哀牢山剪切带, 金矿, 壳幔边界, 岩石圈软流圈边界, 地震波, 接收函数

Abstract: The Indo-Tibetan collision created the huge amounts of ore deposits in the Tibetan Plateau and around areas. Though these
ore deposits have been well studied, it is still a challenge to link the reserve, the migration and the reserve together for an integrated
analysis of the mineralization mechanism. Especially, it is still a gap to analyze the origin of the ore-forming materials in the
crust-mantle scale. Thus, we use conversional seismic waves (i.e. receiver function technique) to study the lithospheric structures
beneath the Daping-Chang’an Au deposits, which present strong evidence for mantle-induced origin, in the south segment of the
Ailaoshan shear zone, southeastern margin of the Tibetan Plateau. We obtained a vertical section across the Au deposits region. The
crust-mantle boundary (Moho) beneath the Au deposits is at 30-40 km depth while presents a clear sharp depression (~3-5 km) and
complex waveforms. The lithosphere-asthenosphere boundary (LAB) on the section is at 60-80 km depth, constraining the thickness of
the lithosphere after the strong thinning. The thinnest lithosphere is beneath the central Simao block and is above a low-velocity zone in 
the uppermost mantle from tomography. As well as the lateral discontinuity at the Moho beneath the deposits, the LAB beneath the
deposits presents a significant lateral discontinuity, indicating lithospheric scale discontinuity. The lateral discontinuities at both the
Moho and the LAB imply the magma channel, which could facilitate a quick migration of the magma from the asthenosphere to surface.
We thought that the lithospheric structure beneath the Daping-Chang’an Au deposits supports the model of the subduction-induced
mantle origin of the ore-forming materials. However, we thought that the shear of the Ailaoshan shear zone dominated the inferred
lithospheric magma channel and that the subduction-induced upwelling of the mantle materials presented memorial contributions to
the formation of the magma channel.

Key words: Ailaoshan shear zone, Au deposit, crust-mantle boundary, lithosphere-Asthenosphere boundary, seismology, receiver
function