Commercial-scale hydrocarbon production from source rocks and reservoirs requires significant capital. It is therefore beneficial to obtain as much accurate data as possible about a formation in order to assess its commercial viability and subsequently to optimize cost and design of development. Hydrocarbon monitoring—especially of methane, ethane, and propane—can be used to predict production, estimate reserves, and assess raw material quality of source rocks and reservoirs. Exploration, reservoir design, and petrochemical manufacturing design are only a few of the many areas that can benefit from comprehensive hydrocarbon monitoring data.