Assertion: aquifer | /r/HasProperty | overlain by aquitard
Facets:
Source sentences:
text: Aquifer is overlain by an aquitard.
text: They are overlain by the upper and middle aquifers and thick clay, coal and limestone aquitards and are underlain by the basement.
text: They are overlain by the upper and middle aquifers and aquitards and are underlain by the basement which was formed between 65 and 545 million years ago.