Development and application of a new inversion algorithm for the time domain induced polarisation data in three dimensions

该项目的目标是利用整个时间序列的信息在时间域中解释激发极化。默认情况下，只使用曲线下方的区域或注入过程中和注入后直接的电压进行解释。目的是开发一种算法，将整个时间序列反演出为地下电导率的3D模型。反演是基于Cole-Cole模型或类似的模型，例如Dias(2000)。一个近似被用来在时间域中快速和直接地计算阶跃响应(Hördt等人)。(2006年)，Hönig和Tezkan(2007年))。首先，对于单独的时间通道，将瞬变信号独立地反转到具有3D DC电阻率代码的地下电导率模型中。因此，得到了模型中每个单元的随时间变化的电阻率。然后可以将随时间变化的电阻率转化为Cole-Cole模型，该模型包含用于表征亚表面的附加参数。整个时间序列的使用需要高标准的数据质量和大量的测量工作。在项目第一阶段使用Terraeter LS测量的数据满足这些要求，并将使用上述算法进行建模。。如果相同轮廓的频域和时间域测量可用，则还将对它们进行比较。

The goal of this project is to use the information of the entire time series for the interpretation of the induced polarization in time domain. By default, only the area below the curve or the voltage during and directly after injection are used for interpretation.The aim is to develop an algorithm which inverts entire time series into a 3D model of the conductivity of the subsurface. The inversion is based on the Cole-Cole model or comparable models e.g. from Dias (2000).An approximation is used to calculate the step response fast and directly in the time domain (Hördt et al. (2006), Hönig and Tezkan (2007)). First, the transients are inverted independently for separate time channels into a subsurface conductivity model with a 3D DC resistivity code. Thus, a time-dependent resistivity for each cell of the model is obtained. The time-dependent resistivity can then be inverted into a Cole-Cole model which contains additional parameters for the characterization of the subsurface. The use of the entire time series requires a high standard of data quality and a large measuring effort. The data measured with the Terrameter LS during the first phase of the project satisfy these requirements and will be modeled with the above-described algorithm. .If frequency domain and time domain measurements are available for the same profiles, a comparison between them will also be made.