* Dollar index <.DXY> falls back after early strength
* Rebel group says it blows up oil facility in Nigeria
* Oil likely to rise to $80-$90 range, Barclays says
* Coming up: U.S. durable good data at 1500 GMT (Updates prices, detail)
By Christopher Johnson
LONDON, March 4 (Reuters) - Oil rose to around $81 per barrel on Thursday, pushing up towards seven-week highs as the dollar pared recent gains.
Reports of an attack on an oil facility in Nigeria also helped support prices, raising worries over production from the Niger Delta after a period of relative calm.
Benchmark U.S. crude oil futures <CLc1> for April rose 6 cents to $80.93 per barrel by 1230 GMT. The contract reached a peak of $81.23 on Wednesday, its highest intraday point since Jan. 12. London ICE Brent <LCOc1> for April was flat at $79.25.
"The dollar has come off its early highs and that weakness has given impetus to oil," said Carsten Fritsch, commodities analyst at Commerzbank in Frankfurt.
"If the market can move up above yesterday's high at $81.23, it would be a technical buy signal for some investors."
The dollar gained around 0.40 percent against a basket of currencies in early trade but then slipped lower and was almost unchanged by midday in London.
A weaker dollar tends to support oil because it makes dollar-denominated commodities cheaper for other currency holders. Currencies have led sentiment in recent weeks, with the focus on the euro zone and worries that a prolonged economic slowdown would hit demand for energy.
News from Nigeria was also supportive. [
]A militant faction in Nigeria's restive Niger Delta said it blew up an oil manifold operated by Italy's Agip <ENI.MI> on Wednesday. There was no immediate independent confirmation.
The attack would be the second in as many days in the Delta, where an amnesty programme last year brought more than six months of peace.
"PRICES TOO HIGH"
The Energy Information Administration said on Wednesday U.S. crude inventories last week rose by a larger-than-expected 4.1 million barrels, while gasoline stocks also increased.
Balancing those figures was data showing total U.S. oil demand grew 0.3 percent in the past four weeks from a year earlier, raising expectations for an end to a 1-1/2-year period of sustained consumption decreases.
China Investment Corp, the country's sovereign wealth fund, believes commodity prices are outpacing the global economic recovery, fuelled by loose monetary policies, a top official said on Thursday.
"Personally, I think the prices are a bit too high, relative to the strength of real economic recovery," Jesse Wang, CIC executive vice president and chief risk officer, said on the sidelines of a conference in Beijing. [
]Oil prices have ranged between $69 and $84 a barrel over the past few months, at a time of uncertainty over the pace of recovery. But a decline in crude stocks and the surplus held in floating storage has set the stage for an increase towards the $80-$90 range, according to Barclays Capital.
The latest data from the Joint Oil Data Initiative (JODI) implies Asian demand has been growing by more than 2 million barrels per day from a year earlier, according to Barclays.
"If Asian demand can grow at such rapid rates when prices are in the $70 to $80 range, then prices cannot stay in that range for much longer," Barclays analysts headed by Paul Horsnell said.
The market awaited data later on Thursday on U.S. durable goods and factory order statistics for January, both at 1500 GMT. On Friday, attention will turn to U.S. non-farm payrolls. (Editing by Anthony Barker)