Towards 3D 9C Elastic Full Waveform Inversion of Shallow Seismic Wavefields - Case Study Ettlingen Line
T.M. Irnaka, R. Brossier, L. Métivier, T. Bohlen and Y. Pan
Event name: 81st EAGE Conference and Exhibition 2019
Session: Poster: FWI Case Studies A
Publication date: 03 June 2019
Info: Extended abstract, PDF ( 9.23Mb )
Price: € 20
Full Waveform Inversion (FWI) is a high-resolution seismic imaging tool, based on an iterative data fitting procedure. In this research, we focus on a near-surface application using three-component sources and three-component receivers (9C). The target is the Ettlingen Line, a defensive trench line located at Rheinstetten, Germany. In this work, we describe the first application of 3D elastic FWI method to a dense 3D dataset equipped with 9C. In practice, due to the limited number of equipment, the acquisition has been split into six parts (each part has the all source locations but only part of receiver locations). This separation leads to an inconsistent dataset concerning both amplitudes and phases. Therefore, a first step has led to the application of matching filter to homogenize the dataset. Several FWI strategies such as Vp - Vs parameter binding, gradient Bessel smoothing, and multi-scale approach have been considered during the inversion process to ensure a good convergence. Starting from a homogeneous model, we can achieve significant improvement in data-fit as well as a realistic reconstructed model. The location and dimension of the trench match with the previous experiments based on the inversion of surface wave dispersion curves with an additional increase in resolution.