The authors investigate the potential of semantic web technologies to enhance "Virtual Fieldwork" resources and learning activities in the Geosciences. They consider the difficulties inherent in the concept of Virtual Fieldwork and how these might be reconciled with the desire to provide students with "authentic" tools for knowledge construction evident in existing Virtual Field Sites. Following the progress in design and use of Virtual Field Sites in one UK university, the authors investigate how emerging technologies might produce a shift in thinking about the nature and role of Virtual Field Sites from being primarily visual representation tools to sites for the development of skills necessary in practice. This would represent the integration of such online tools into an expanding and evolving set of discourses and practices, rather than replacing or contributing to the loss of traditional disciplinary activities such as the collection by students of their own field data. (Contains 3 figures.)