* LME copper up over 8 pct on week after Wednesday rally * LME copper may fall back to $7,615-technicals * Coming Up: U.S. non-farm payrolls, 1330 GMT (Updates prices) By Manolo Serapio Jr SINGAPORE, Dec 2 (Reuters) - London copper futures edged higher on Friday and were on track for their first weekly gain in five weeks, after a rally fed by a liquidity injection into distressed European banks which may be sustained if U.S. employment data beats expectations. U.S. nonfarm payrolls are expected to have increased 122,000 last month after October's 80,000 gain. But a higher-than-expected ADP employment report earlier in the week, which showed U.S. companies adding 76,000 jobs more than forecast, could lead to a stronger nonfarm payrolls, analysts said. "A large majority of the market is still short and if the numbers are positive, I think there'll be more short covering," said Nirrav Sharma, marketing manager at Singapore-based trading house G-Steelmet. "Copper prices remain well supported. If there's any risk, the risk is to the upside, the downside is very limited." Three-month copper on the London Metal Exchange rose half a percent to $7,831 a tonne by 0708 GMT. For the week, copper is up more than 8 percent and is on course for its first weekly gain since the end of October. LME copper surged more than 5 percent on Wednesday in its biggest single-day rise in a month when global central banks, from the U.S. Federal Reserve to the European Central Bank, agreed to provide cheaper funding to European banks facing a credit crunch. But prices fell around 1 percent on Thursday after investors realised that far more needed to be done to put the euro zone back on its feet. That shifted focus to slowing growth in Europe and China, eclipsing even Beijing's move to cut bank reserve requirement for the first time in three years, announced late on Wednesday. Manufacturing activity contracted in the euro zone and China in November, underscoring the ripple effects from Europe's debt crisis. But the United States bucked the trend, with its manufacturing sector rebounding to its strongest level since June on the strength of new orders. The most-active February copper on the Shanghai Futures Exchange gained 0.2 percent to close at 58,060 yuan a tonne. Investors are also looking to the next European Union summit on Dec. 9 where officials could adopt more measures to tackle the two-year-old euro zone debt crisis. The new head of the European Central Bank signalled on Thursday that the ECB stood ready to act more aggressively to fight Europe's debt crisis if political leaders agree next week on much tighter budget controls in the 17-nation euro zone. "Wednesday's liquidity injection has been a game changer in terms of the technicals, where a number of resistance levels have now been taken out in the metal charts," INTL FCStone analyst Edward Meir said in a note. "However, the more relevant question is whether or not there has been an underlying shift in the fundamentals, and in this regard, the answer is not as clear-cut." Base metals prices at 0708 GMT Metal Last Change Pct Move YTD pct chg LME Cu 7831.00 41.00 +0.53 -18.43 SHFE CU FUT FEB2 58060 100 +0.17 -19.19 LME Alum 2117.50 -27.50 -1.28 -14.27 SHFE AL FUT FEB2 16255 60 +0.37 -3.47 HG COPPER MAR2 356.10 2.70 +0.76 -19.79 LME Zinc 2026.00 -19.00 -0.93 -17.44 SHFE ZN FUT MAR2 15815 -05 -0.03 -18.79 LME Nickel 16974.00 189.00 +1.13 -31.42 LME Lead 2087.00 -18.00 -0.86 -18.16 SHFE PB FUT 15650 -135 -0.86 -14.71 LME Tin 20075.00 -25.00 -0.12 -25.37 LME/Shanghai arb 233 Shanghai and COMEX contracts show most active months ^ LME 3-m copper in yuan, including 17 pct VAT, minus SHFE third month

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