Columbia subject headings:
Gas reservoirs--Rocky Mountains Region.
Hydrocarbons--Rocky Mountains Region.
Petroleum--Geology--Rocky Mountains Region.
Sandstone--Rocky Mountains Region.
Harvard subject headings:
Geology, Structural--Rocky Mountains Region.
Geology, Structural--Rocky Mountains.
Petrogenesis--Rocky Mountains Region.
Petrogenesis--Rocky Mountains.
Petroleum--Geology--Rocky Mountains Region.
Petroleum--Geology--Rocky Mountains.
Princeton subject headings:
Gas reservoirs--Rocky Mountain Region.
Hydrocarbons--Rocky Mountain Region.
Petroleum--Geology--Rocky Mountain Region.
Sandstone--Rocky Mountain Region.