(Adds analyst estimates, details on Q3 results)
LIMA, Oct 27 (Reuters) - Global miner Southern Copper Corp said on Tuesday its net profit tumbled 70 percent to $98.4 million in the third quarter after copper prices fell sharply.
The results were well below the mean profit estimate of $170 million, according to Thomson Reuters I/B/E/S. The company's shares were down nearly 1 percent in New York trading.
Sales fell about 23 percent in the quarter, tracking a nearly 25 percent year-on-year drop in copper prices.
Southern Copper's $100 million acquisition of the El Pilar Mexican copper project also weighed on results.
The company said an 8.8 percent rise in copper production in the first nine months of 2015 helped offset the slump in prices.
The miner said it expects to increase production capacity to 1.165 million tonnes of copper by 2018. (Reporting by Mitra Taj; Editing by Chizu Nomiyama and Jeffrey Benkoe)