Oil and natural gas (hydrocarbons) develop and accumulate in sedimentary basins. These geological areas were created millions years ago in marine and ocean environments. They result from deposition and accumulation of billions of tons of sediments, sand grains, organic remains, fossils and dust. Petroleum system is the basic scheme of hydrocarbon exploring. Each system is coming from a source rock which is rich in organic matter that has allowed generation, and porous rocks that has allowed migration and accumulation of hydrocarbons in the traps of the sedimentary basin.

In Quebec, presence of a petroleum system has been proved in at least three basins :

• The St-Lawrence Lowlands
• Gaspesia
• St-Lawrence Gulf

Current knowledge also allowed us to target interesting sedimentary areas. According to Junex, five exploring targets seem to be promising and should be priority ones :

• Exploration of Silurian and Devonian basins of Gaspesia
• Exploration of hydrothermal breccia
• Exploration of Shale gas
• Exploration of overthrust belts at the front of the Appalachian
• Exploration of recent hydrocarbons system in Quaternary sediments

These targets indicate important similarities with many oil-producing regions elsewhere in North America Paleaozoic basins. The following chart shows discoveries made in equivalent formations in the Palaeozoic Basins.

Localization	Geological Formation	Production
Finger Lakes, NY (Talisman Energy)	Trenton/Black River	+100 Mmcf a day of natural gas
Port-au-Port, Terre-Neuve (EnCana)	Équivalent du Beekmantown	1,500 barrels a day (test)
Roane County, Virginie Ouest (CNR)	Trenton	+50 Mmcf a day of natural gas
Val verde, Texas	Équivalent du Beekmantown	+1,000 Bcf of natural gas
Fort Worth Basin, Texas	Barnett Shale	Annual Production : 500 Bcf
Albion-Scipio, Michigan	Trenton/Black River	+1 000 Bcf of natural gas and 200 million barrels of oil
Nord du Michigan	Antrim Shale	Annual Production : 100 Bcf
Dover et équivalents, Ontario	Trenton/Black River	15 million barrels of oil and 25 Bcf