The water-energy-food nexus of unconventional oil and gas extraction in the Vaca Muerta Play, Argentina

摘要

Vaca Muerta is the major region in South America where horizontal drilling and hydraulic fracturing techniques are used to extract unconventional shale oil and gas. Despite the growing interest in the Vaca Muerta resources, there is only a limited understanding of the impacts that their extraction could have on local water resources. This study uses a water balance model to investigate the hydrological implication of unconventional oil and gas extraction in this region. We find that, with current rates of extraction, water scarcity is observed for four months a year. We also find that water consumption per fractured well increased 2.5 times in the period 2012-2016 and produced water from unconventional shale formation sharply increased from roughly zero to 1.15 x 10(6) m(3) y(-1) in the 2009-2017 period. Our projections estimate that in this region future water consumption for unconventional oil and gas extraction will increase 2.2 times in the 2017-2024 period reaching 7.40 x 10(6) m(3) y(-1). The consequent exacerbation of current water scarcity will likely lead to competition with irrigated agriculture, the greatest water consumer in this semiarid region. Produced water recycling, domestic wastewater reuse, brackish groundwater use, and waterless unconventional oil and gas extraction technologies are some of the strategies that could be adopted to meet future additional water demand. Our results estimate the likely range of water consumption and production from hydraulic fracturing operations in the Vaca Muerta region under current and future conditions. These results could be used to make informed decisions for the sustainable water management in this semiarid region of Argentina. (C) 2018 Elsevier Ltd. All rights reserved.