* FTSEurofirst 300 up 1 pct, Euro STOXX 50 up 1.2 pct
* Rebound seen technical; all eyes on Japan crisis
* UBS analysts see buying opportunities
* For up-to-the-minute market news, click on
By Blaise Robinson
PARIS, March 17 (Reuters) - European share prices were higher on Thursday morning, regaining some ground after a 7 percent slide over the past six sessions, but the rebound was seen as technical as Japan's nuclear plant crisis kept investors on edge.
At 0935 GMT, the FTSEurofirst 300 index of top European shares was up 1 percent at 1,077.89 points, bouncing back from a 3-1/2 month low hit on Wednesday on rising fears Japan's disaster would derail the global economic recovery.
The FTSEurofirst 300, as well as the Euro STOXX 50, UK's FTSE 100, Germany's DAX index and France's CAC 40 were all deep in 'oversold territory' on Thursday before the bell, with their relative strength index (RSI) below 30, pointing toward a technical rebound.
U.S. stocks dropped 2 percent on Wednesday, with the S&P and Nasdaq turning negative for the year, while Japanese stocks resumed their slide and the yen surged to a record high against the dollar.
"The drop has been violent, but the newsflow remains very alarming. There is short covering at this point, and we continue to see outflows," said David Thebault, head of quantitative sales trading, at Global Equities, in Paris.
"Stocks might look oversold on the short term, but they are not if we're heading into a bear market. The Japanese crisis could have severe consequences for the global economy. Just think about divestment from Asian central banks and investors, that's the real fear here."
On Thursday Japanese military helicopters dumped water on the overheating nuclear plant, while the top U.S. nuclear regulator warned that the cooling pool for spent fuel rods at reactor No.4 may have run dry and another was leaking.
The country could be heading back into recession, with trillions of yen wiped off share markets and a surging yen currency squeezing the key export sector, adding to fears over supply chain disruptions.
Heavyweight mining stocks featured among the biggest gainers, with BHP Billiton up 2.4 percent and Xstrata up 1.8 percent. But the Stoxx 600 Europe basic resources index is still down 12 percent in 2011, Europe's worst sector performance so far this year.
Around Europe, UK's FTSE 100 index was up 0.9 percent, Germany's DAX index up 1.1 percent, and France's CAC 40 up 1.1 percent.
"This has been a shock to the system and investors have become very emotional. But our quant model so far is telling us this isn't the start of a new regime, the world economy is not going into a double-dip recession," said Hans-Olov Bornemann, head of the global quant team and senior portfolio manager at SEB Asset Management, in Stockholm.
"We're still long equities, although we've reduced our exposure, and we're still short on bonds. The market has already priced in pretty bad scenarios, but the global recovery story is still intact," said Bornemann, whose SEB Selection Asset Fund manages 1.37 billion euros.
After screening through the beaten-down European stocks, UBS analysts said stocks with limited exposure to Japan have been "unjustifiably" oversold and represent "attractive buying opportunities."
"Although risks are ongoing, European equities now trade on single-digit multiples --9.4 times 2012 expected earnings. We see value," they said in a note.
"Back in the mid-1990s, 2.5 percent of Eurozone exports went to Japan; now it is 1 percent. For corporates, we estimate that sales to Japan generate around 3 percent of total revenues --ex-financials--, although of course for some sectors, such as luxury goods, the figure is materially higher." (Editing by Greg Mahlich)