Compared with previous years, activities in pursuit of potential mergers and acquisitions (M&A) in Australia's mining sector will be mostly played on by the country's mid-tier and junior mining players in 2012.

This, as total global value of M&As in mining and metals jumped 43 per cent in 2011, Ernst & Young said in its annual mining-transactions report released on Monday.

As second-tier miners continued to merge and combine funds and expertise all throughout 2011, only a few possible M&A opportunities are left in Australia's $1 billion mining territory zone, Paul Murphy, Ernst & Young's Australia and Asia-Pacific transactions leader, said.

Based on the report, there are only a few potential $1 billion-plus worth deals possible for Australia's mining industry this year.

In 2011, the number of Australian M&A dropped 17 per cent from the previous year, to 242, although total deal value grew 64 per cent to $38.6 billion, which includes BHP Billiton's two US shale gas acquisitions.

The year 2012 will likely see the same number of deals and value, although Murphy said the trend is more seen on the mining services companies, as miners seeking to limit future and possible risk supply challenges look to mining services companies as targets.

"While uncertainty and volatility is likely to continue to play out on the world stage, the appetite by management and investors for growth is again likely to provide sufficient stimulus for strong M&A activity in Australia in 2012,'' he said.

"What we've seen in the mining sector in 2011 is the commodity prices are holding, the balance sheets are de-leveraged and the appetite is there for growth and development but the available targets are not quite going to match up with that," Murphy said. "The availability of targets could be a constraint and there is still a reluctance and impediment to doing $10bn-plus deals."

Meanwhile, robust demand fundamentals, strong balance sheets and appetite for growth will continue to feed the global trend of M&As in mining and metals in 2012.

In the same report, Ernst & Young said global M&A in the mining sector soared to $162.4 billion in 2011 from $113.7 billion in 2010, highlighted by megadeals of $1 billion or more which contributed for two-thirds of total deal value.

Global deal volume in 2011, however, plummeted 10 per cent to only 1,008 deals compared with 1,123 deals the previous year. Limited capital availability lessened the chances, if not totally eliminated, the capacity of smaller players to conduct business and forge deals.

But miners are willing to push through with planned initial public offerings (IPOs) in order to source and secure funds.

"If markets stabilize this may happen in the second half of 2012," Lee Downham, Ernst & Young's global-mining-and-metals transaction leader, said.

A number of IPOs got suspended in 2011 due to lack of investor confidence and instability in equity markets. There were 145 listings in 2011, 18 per cent down compared from 177 in 2010. Total proceeds from IPOs in 2011 was a measly $17.4 billion, down 3 per cent from a year ago. And if the IPO of Glencore International PLC is excluded from the tally, total proceeds falls further to $7.4 billion, 59 per cent below 2010 proceeds, Downham said.