Higher-tier artefacts can become 'cobblestoned' when they are in a security field or protection system such as the one that you encounter
You will usually receive a warning about this before you reach the danger point.
More often, Artefacts can be Cobblestoned when affected by by a strong Psi field... e.g.
It can also happen when you are near a strong Controller. There is no advance warning in these cases.
Lower-tier (basic) artefacts (Medusa, Quirk, etc.) are usually unaffected by cobblestoning.