According to a 2011 estimate, the Central and South America hold about 269 trillion cubic feet (TCFG).  Venezuela hold the largest reserves at around 179 TCFG, but due to a lack of general infrastructure and development, they’re currently only producing 0.89 TCFG, annually.
Mexico is currently a net importer of natural gas with increasing demand, and contains 17.3 TCFG of proven natural gas reserves. Analysts expect this to change with such proven reserves available. However, its production from unconventional resources is slow to develop and they’re unable to keep up with increasing demand as a result. Therefore, it is expected that Mexico will increase imports of pipeline gas from the United States and liquefied natural gas (LNG) from other countries.
Argentina is currently the largest producer of natural gas in Central & South America, accounting for more than 40% of the regions total production in 2008. It is also leading in the pursuit of tight and shale gas exploration, with the first horizontal well with multiple fracture stages drilled in 2010.
The Federal Government of Argentina owns all subsurface mineral rights within the country as well as control the split between the federal and provincial governments. As a result, the majority of the regulation of gas production resides within the power of the provinces. However, certain states are adopting federal legislation for their own benefit. The vast majority of the unconventional tight sand and shale gas development are occurring in Neuquén region.
In May 2012, the Argentine legislature passed the “YPF Expropriation Act”, which re-nationalized 51% of the shares of YPF from Repsol. The remaining 49% shares were left intact, some of which continue to be owned by Repsol. The YPF Expropriation Act also declared hydrocarbon self-sufficiency a national priority and established policy goals of promoting investment to maximize resources.
Natural gas production in Central & South America is expected to increase by 85% from 2008 to 2035. The largest portion of development is projected to take place in Brazil, where large new oil and gas reservoirs have recently been discovered, and will increase natural gas production once the infrastructure for extraction and transport is developed.
The embedded PDF below is a detailed analysis of undiscovered natural gas and oil in the Caribbean, Central America, and South America from the United States Geological Survey:
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