Sand and gravel that form productive aquifers are generally in the lower part of the Seymour Formation.
(Sand and gravel; form; productive aquifers) (Sand and gravel that form productive aquifers; are generally; in the lower part of the Seymour Formation)
Sand and gravel Sand and gravel that form productive aquifers
form are generally
productive aquifers
in the lower part of the Seymour Formation