According to Bennison, most of Montgomery County is covered by limestones, sandstones, and shales deposited during the Pennsylvanian Period, about 300 million years ago.
(most of Montgomery County; is covered; by limestones, sandstones, and shales) (shales; deposited; T:during the Pennsylvanian Period; T:about 300 million years ago)
most of Montgomery County shales
is covered deposited
by limestones, sandstones, and shales
T:during the Pennsylvanian Period T:about 300 million years ago