* Codelco, Anglo American mines operational after tremors
* Copper prices boosted slightly by aftershock news
* Oil refineries shut from quake suffer no new problems (Updates with details on fuel inventories, copper prices, paragraphs 9, 10, 13-17)
By Mica Rosenberg and Alonso Soto
SANTIAGO/TALCAHUANO, March 11 (Reuters) - Chile's mining and refinery sectors escaped damage on Thursday as a series of powerful aftershocks rocked the world's largest copper producer in the wake of one of the biggest earthquakes ever recorded.
Chile's Codelco and global miner Anglo American (AAL.L) said all their mines were unharmed after seven tremors -- one as strong as 6.9-magnitude -- rocked the southern-central area near the epicenter of the massive Feb. 27 earthquake that killed hundreds of people.
The latest aftershocks shook Rancagua, a city near Codelco's giant underground mine El Teniente, just as new conservative president Sebastian Pinera was being inaugurated,
"We do not have any reports of damage," a Codelco spokeswoman said.
Dozens of aftershocks have so far caused no new fatalities or serious destruction in the days following the 8.8-magnitude quake which knocked down roads, bridges and thousands of houses.
The bulk of Chile's key copper industry is located in the north, far from the hardest hit areas.
El Teniente and Andina, Codelco's second- and third-largest mines by production with combined annual output last year of 614,000 tonnes, were only briefly offline after the initial quake, and were operating normally on Thursday.
"Everything is normal. No problems. There was no damage to the operations in the central region," Marcelo Esquivel, Anglo American's spokesman in Chile's capital Santiago told Reuters.
News of the aftershocks helped lift copper prices on Thursday, but fears that China may tighten monetary policy limited gains.
U.S. copper futures' most active contract, May HGK0, settled up 0.90 cent, or 0.3 percent, at $3.3770 per lb on the New York Mercantile Exchange's COMEX division. On the London Metal Exchange, copper CMCU3 also ended up 0.3 percent, or $24, at $7,464 a tonne.
Two of Chile's top oil refineries damaged by the original quake remain shut. The Bio Bio refinery and the smaller Aconcagua refinery suffered no additional damage from the aftershocks, although workers were evacuated for safety reasons, union leaders at both plants said.
The Bio Bio refinery could be offline for two to three months, the head of the union there has said.
Chile's new Mining Minister Laurence Golborne told reporters on Thursday evening that Aconcagua would come back on line this week and that he planned to visit the refineries with the head of state-oil company ENAP to survey the damage.
Golborne also said Chile had arranged two diesel shipments that would arrive in "coming days" but did not clarify whether those were in addition to fuel cargoes announced earlier.
Chile has increased fuel shipments to cover shortages from the refinery closures.
"We have enough inventories to cover demand for this fuel in the next week. We will not have any problems for at least until the end of April," Golborne said.
The navy sent all boats out to open sea, including tankers, after a tsunami alert as a preventive measure but by the late afternoon the ships were returning to port after the alert was lifted. (Additional reporting by Alvaro Tapia; Editing by David Gregorio)