AN international geology expert claims the mining of shale gas causes less damage to the environment than extracting coal-seam gas which is dividing communities in Australia.

Mr Scott Tinker of the University of Texas the US had gone down the CSG route in the late 1990s before moving to shale gas in the past few years. He said that "The big challenge with unconventional gas such as these two is how it affects water, but shale gas is extracted from considerably deeper than coal seam gas."

He added that "The water you're extracting with coal-seam gas is often part of the aquifer system and that can affect water systems."

Shale gas makes far more use of hydraulic fracturing the technique of blasting underground known as fracking than CSG, but Professor Mr Tinker said the technology was improving all the time so the risks were becoming more manageable. He said that "It's one of a lot of things which actually doesn't affect the environment all that much, but I understand that people are worried about it."

Mr Ron Oxburgh Former British chief scientist told the conference there was no silver bullet for reducing greenhouse emissions while demand for energy was still increasing rapidly. He said replacing coal with gas was one of the quickest and least painful ways to cut emissions.

He said advances in technology had made the mining of gas especially shale oil and CSG more efficient and safer.

The first advance was the rise of vertical drilling which enabled a drill to bore down far into the earth and then proceed horizontally. This made it possible to drill at far greater depths than previously.

The second was better imaging and the third was better fracking practices.

Mr Lord Oxburgh has also chaired the British arm of Shell and while he has previously warned about the dangers of global warming, he said fossil fuels would be around for decades yet.

He said "In some ways, it doesn't matter too much what we do in Europe and even Australia the most important thing is in Asia with the countries that are big consumers, China and India."

He strongly advocated more research into carbon capture and storage, known as clean coal technology.