GS0401: Energy production services; material treatment services, namely, the mechanical and chemical processing and transformation of organic and inorganic substances, namely, oil, natural gas and liquid natural gas obtained from hydrocarbon wells and reservoirs
GS0041: Hydrocarbon fuels, namely, oil, natural gas and liquid natural gas; industrial oils and greases; motor fuels and oils; crude oil
GS0421: Energy exploration services, namely, exploration services in the fields of oil, gas, liquid natural gas and other hydrocarbons; petroleum exploration services; scientific services, namely, research and development provided by technically-oriented professionals, namely, geologists, chemists, physicists, geophysicists, engineers and computer specialists