US STOCKS-Wall St ends down after Fed stokes global economic fears
* Fed holds rates at near-zero
* Options expirations adds to trading volume
* All 10 S&P sectors lower; led by energy
* Industrials, materials and financial sectors hard-hit
* Indexes down: Dow 1.74 pct, S&P 1.61 pct, Nasdaq 1.36 pct (Updates to close, adds commentary, volume)
By Sinead Carew
Sept 18 (Reuters) - Wall Street stocks closed lower on Friday in heavy trading as the Federal Reserve's decision to keep interest rates near zero fueled concerns about the potential impact of continuing weak global growth on U.S. corporate earnings.
Apart from the state of the world economy, the Fed cited financial market volatility and sluggish inflation at home in its decision on Thursday, while leaving the door open for a modest policy tightening later this year.
Friday's volatility was also likely exacerbated by so-called "quadruple-witching", when options on stocks and indexes, and futures on indexes and single-stocks all expire, prompting investors to buy or sell shares to cover expiring contracts. Continuación...