论文标题
关于使用TravelTime的各向异性和不均匀性参数估计
On anisotropy and inhomogeneity parameter estimation using traveltimes
论文作者
论文摘要
我们考虑了一种各向异性的不均匀模型，以模拟测得的垂直远程训练性旅行时间。在此模型中，我们假设速度随深度和各向异性的线性增加是椭圆速度依赖性的结果。使用一系列的来源到单个接收器，我们将测量和建模的旅行时间之间的最小二乘残差最小化，以估计地下的各向异性和不均匀性参数。为了验证该方法，我们为一层和两层模型构建合成旅行时间数据，并执行旅行时间倒置。我们证明参数估计固有的固定范围的收敛性规范和模型参数限制是合理的。为了确定方法的实用性，我们在噪声影响下评估结果的可靠性。从该评估中，我们可以辨别这两个模型的噪声阈值，并确定噪声限制对于增加模型复杂性是严格限制的。我们使用相同的方法来估计参数，以进行实际数据，并以讨论结果进行结论。
We consider an anisotropic inhomogeneous model to simulate measured vertical-seismic-profile traveltimes. In this model, we assume that velocity increases linearly with depth and anisotropy is the result of elliptical velocity dependence. Using a series of sources in a line to a single receiver, we minimize the least-squares residual between measured and modelled traveltimes to estimate the anisotropy and inhomogeneity parameters of the subsurface. To verify the approach, we construct synthetic traveltime data for a one- and two-layer model and perform the traveltime inversion. We justify the convergence-ensuring specifications and model-parameter restrictions that are intrinsic to the parameter estimation. To determine the approach's practicality, we assess the reliability of results under the influence of noise. From this assessment, we discern the noise threshold for both models and determine that the noise restriction is severely restrictive for increasing model complexity. We estimate parameters, using the same methodology, for a real-data case and conclude with a discussion of results.
