Gás de xisto: uma nova fronteira para a mineração

Abstract

Shale gas is a fossil fuel whose exploration became economically viable in the United States in the 2000s, due to innovations and improvements made in the processes of hydraulic fracturing and horizontal drilling (processes that already existed since the 40s and 80s, respectively). Outside the U.S., despite several technically recoverable reserves having already been mapped, the economical viability of the exploration is, for the most part, unknown, given that it depends on regional factors (such as geology and local operational costs) not yet analyzed. However, the interest for shale gas has been growing around the world, and countries like Australia and China are beginning to analyze the economical viability of exploring their reserves (this tendency hasnt been observed in Brazil, where the government is focusing on the exploration of conventional gas and oil from offshore reserves). This interest has environmental and economical reasons: shale gas is considered a cleaner energy source, since the carbon emissions of this gas are lower than the emissions of other fossil fuels; and the great volume of shale gas resources mapped around the world could represent a revolution in the global energy landscape, being capable of turning energetically self-sufficient some of the worlds greatest nations, such as the U.S., and of reducing the global dependency on the fossil fuels from Russia and the Middle East. Besides the economical viability, the environmental impacts associated with the exploration of shale gas (earthquakes, water and soil contamination, among others) have also been intensely analyzed, and constitute a big obstacle to the development of this activity. To overcome this hurdle, it is necessary to develop industrial good practices and to adopt governmental regulations that aim the extinction or the mitigation of the potential environmental impacts of shale gas exploration.