section_path: Applied geology/Economic geology/Petroleum geology
section_name: Petroleum geology
paragraph_text: Petroleum geology
  
  Petroleum geologists study the locations of the subsurface of the Earth that can contain extractable hydrocarbons, especially petroleum and natural gas. Because many of these reservoirs are found in sedimentary basins, they study the formation of these basins, as well as their sedimentary and tectonic evolution and the present-day positions of the rock units.