Estimation and removal of complex near surface effects in seismic measurements

Abstract

A seismic survey is conducted to acquire data which can be used to image the earth's discontuinities. On land, the near surface disturb the data severely, due to its strongly heterogeneous character. Commonly used methods use single trace methods to correct for these near surface effects based on simplified models and are known as 'statics', refering to a single and surface consistent irrespective of recording time. As the near surface problem is a wave-propagation problem, this thesis estimates the propagation characteristics of the near surface independend of the underlying earth model. The so called focusing operators, representing these propagation characteristics, are then used for true amplitude redatuming of the measurements to a level underneath the near surface in a least squares sense and to estimate an accompanying near surface model.