【摘要】 本文研究了第一菲涅尔带约束下的波动方程Born/Rytov近似层析反演方法,其中如何求取敏感核函数和旅行时残差是关键技术。以频率域波动方程Born和Rytov近似为基础,推导出建立在带限地震波理论基础上的波动方程Born/Rytov近似走时敏感核函数,同时依据Rytov近似求取走时残差。与常规单射线走时层析方法不同,改进的速度反演方法提高了反演的稳定性。模型试算与实际资料处理结果表明,相对于传统的单射线走时层析和波形反演方法,该方法具有更高的反演精度与计算效率。更多还原

【Abstract】 This paper discusses Born/Rytov approximation tomographic velocity inversion methods constrained by the Fresnel zone. Calculations of the sensitivity kernel function and traveltime residuals are critical in tomographic velocity inversion. Based on the Born/Rytov approximation of the frequency-domain wave equation, we derive the traveltime sensitivity kernels of the wave equation on the band-limited wave field and simultaneously obtain the traveltime residuals based on the Rytov approximation. In contrast to single-ray tomography, the modified velocity inversion method improves the inversion stability. Tests of the nearsurface velocity model and field data prove that the proposed method has higher accuracy and Computational efficiency than ray theory tomography and full waveform inversion methods.更多还原