In this paper, we demonstrate how analytic provenance can be exploited to re-construct user trust in a guided Visual Analytics (VA) system, and suggest that interaction log data analysis can be a valuable tool for on-line trust monitoring. Our approach explores objective trust measures that can be continuously tracked and updated during the exploration, and reflect both the confidence of the user in system suggestions, and the uncertainty of the system with regards to user goals. We argue that this approach is more suitable for guided VA systems such as ours, where user strategies, goals and even trust can evolve over time, in reaction to new system feedback and insights from the exploration. Through the analysis of log data from a past user study with twelve participants performing a guided visual analysis task, we found that the stability of user exploration strategies is a promising factor to study trust. However, indirect metrics based on provenance, such as user evaluation counts and disagreement rates, are alone not sufficient to study trust reliably in guided VA. We conclude with open challenges and opportunities for exploiting analytic provenance to support trust monitoring in guided VA systems.