Subsequently, the research team " lightly disked " the site to perform a " controlled surface collection . " The surface collection yielded a wide range of artifacts including different types of glass, ceramics, personal items, and small amounts of brick and stone structural materials.
2.
I think my example here also answers your question on why'to disc'becomes ( or would become, if it is in fact a verb, as I shall find out after this post : ) )'disking'and'disked'in its inflected forms-there is an alternative spelling in the infinitive / present tense with the'- k'spelling already, and this would be taken into the inflected forms.