The legal effects of an archaeological discovery can depend on a number of different circumstances.
First, many discoveries occur within the context of pre-planned archaeological research, conducted by professionals under the auspices of the requisite provincial/territorial authorization. Such research is conducted with the consent of the landowner. The normal procedure, on making a discovery, would be to notify the landowner to ensure that any threatening work in the vicinity is halted and that the site is secure. That is usually uncontroversial, since the landowner would not have had the archaeologist on the property unless there was some expectation this might occur. If the discovery was of human remains that were not very old, the archaeologist would also ensure that the police were contacted immediately.
Otherwise, the archaeologist would also notify the provincial/territorial archaeological authorities and (as described later) consult with likely descendants of the people whose property or remains had been discovered.
Accidental or fortuitous discoveries are a different matter. There are fundamental legal differences in the treatment of discoveries of:
human remains and
Each of these will be discussed in turn.