Abstract: Method for adapting a template to a target data set. The template may be used to remove noise from, or interpret noise in, the target data set. The target data set is transformed (550) using a selected complex-valued, directional, multi-resolution transform (‘CDMT’) satisfying the Hubert transform property at least approximately. An initial template is selected, and it is transformed (551) using the same CDMT. Then the transformed template is adapted (560) to the transformed target data by adjusting the template's expansion coefficients within allowed ranges of adjustment so as to better match the expansion coefficients of the target data set. Multiple templates may be simultaneously adapted to better fit the noise or other component of the data that it may be desired to represent by template.

Abstract: A method for suppressing measurement system signature, or artifacts, that arise when controlled source electromagnetic survey data are inverted to obtain a resistivity image of a subsurface region. The method involves identifying regions (47) where the image has low or rapidly varying sensitivity to data acquired by a given receiver, typically regions close to and under the given receiver. Then, in the iterative inversion process where a resistivity model is updated to minimize an objective function, the model update is modified (48) to reduce the impact of such low sensitivity regions on the update.

Abstract: Method for updating a velocity model (926) for migrating seismic data using migration velocity scans with the objective of building a model that reproduces the same travel times that produced selected optimal images from a scan. For each optimal pick location (914) in the corresponding test velocity model (916), a corresponding location is determined (922) in the velocity model to be updated, using a criterion that the travel time to the surface for a zero offset ray (918) should be the same. Imaging travel times are then computed from the determined location to various surface locations in the update model (924), and those times are compared to travel times in the test velocity model from the optimal pick location to the same array of surface locations. The updating process consists of adjusting the model to minimize the travel time differences (934).