PowerPoint Presentation

Professor Garry WillgooseThe university of NewcastleCoal Seam Gas, water, and fraccingintroductionTwo forms of gas production are confused. They are different in both extraction process and impacts. Its important to distinguish between them so you are focused on the relevant impacts.Coal Seam gas vs Shale gasExtractionFraccingImpacts and how they differ The difference between shale gas and coal seam gasShale Gas is traditional natural gas (just like North west shelf) only in rocks (typically shales) that are very fine grained and so the gas does not flow out readily. The gas is trapped in the pores in the rock between the rock grains. It is a mixture of methane, butane and other hydrocarbons. Some condensate (light oil) typically produced.Coal Seam Gas is gas that is chemically attached (as a result of water pressure) to the coal in coal seams (the process is called adsorption). When the water pressure is reduced the gas detaches from the coal and bubbles out (like gas in a bottle of soft drink). Its is a mixture of methane and carbon dioxide. No condensate produced.EXISTING shale gas and coal seam gas productionUSA Production2000: 0% Shale Gas, 5000 mg/l), alkaline and sodic. This means the water is not suitable for irrigation or other productive use straight from the well.Production water has been the main problem in Qld and near Narrabri (Eastern Star). There are proposals to desalinate water for use in irrigation but to date only limited trials.Santos @ Fairview in SE Qld, 100kl/day from 200 wells, worlds largest CSG irrigation trial.sWater and GAS flow over timeOver a few months it looks like