Activist Jonathan Deal was awarded the Goldman Environmental prize on Monday for his efforts in opposing hydraulic fracturing, or fracking, in the Karoo.
The cash prize, worth US150,000 (about R1.4m), was handed to Deal and five other recipients in San Francisco to honour grassroots environmental activism.
"This award coincided with the end of an especially difficult year in the hard fought campaign against fracking," Deal said in a press release issued on his behalf.
"I have done nothing in this campaign for my personal benefit; however, the recognition from people on the other side of the world has been a great encouragement."
Deal created the Treasure Karoo Action Group (TKAG) in early 2011 to oppose the introduction and licensing of shale gas extraction through fracking. The group is run entirely by volunteers.
Mineral Resources Minister Susan Shabangu declared a moratorium on fracking last April and established a multi-disciplinary task team to prepare a report for her.
In September, she announced "normal" geological exploration would be allowed to establish the size and potential of the shale gas reserve.
According to her team's report, there is an estimated "technically recoverable" 485 trillion cubic feet of gas in the Karoo Basin.
It is believed five companies, including Shell, applied to explore for shale gas.
"Licences can now be issued at any time, but we will be ready to appeal the issuing of any licences," Deal said.
He believed the applicants' environmental management plans were flawed.