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A 40-channel wide‐aperture ground penetrating radar (GPR) data set was recorded in a complicated fluvial/aeolian environment in eastern Canada. The data were collected in the multichannel format usually associated with seismic reflection surveys and were input directly into a standard seismic processing sequence (filtering, static corrections, common‐midpoint gathering, velocity analysis, normal‐ and dip‐moveout corrections, stacking and depth migration). The results show significant improvements, over single‐channel recordings, in noise reduction and depth of penetration (by stacking), and in spatial positioning and reduction of diffraction artifacts (by migration). These characteristics increase the potential for reliable interpretation of structural and stratigraphic details. Thus, without having to develop any new software, GPR data processing technology is brought to the same level of capability, flexibility, and accessibility that is current in seismic exploration.

In an attempt to shape the development of nanotechnologies, ethics policy programs promote engagement in the hope of broadening the scope of considerations that scientists and engineers take into account. While enhancing the reflexivity of scientists theoretically implies changes in technoscientific practice, few empirical studies demonstrate such effects. To investigate the real-time effects on engineering research practices, a laboratory engagement study was undertaken to specify the interplay of technical and social considerations during the normal course of research. The study employed an ethnographic invention in the form of a decision model to structure reflection on ongoing social processes. A short series of interactions with one engineering researcher illustrates the deployment of the model in the form of an interview protocol. The cultural embedment of the protocol allowed it to function as a feedback mechanism, creating a more self-critical environment for knowledge production, and perturbing the system in research-tolerable ways.

A single-channel, ground-penetrating radar (GPR) profile portrays a distorted, unfocused image of subsurface structure due to apparent position shifts associated with dipping reflectors and to diffractions from corners and edges. A focused image may be produced from such data by using any of the migration algorithms previously developed for seismic data; we use reverse-time migration based on the scalar wave equation. Field work was performed over a simple stratigraphic soil sequence and a complicated fluvial environment. In the migrated images, reflector continuity is enhanced and the level of detail available for highresolution interpretation is significantly increased.