S&P, Nasdaq open lower; Chevron lifts Dow

(Reuters) - The S&P 500 index and the Nasdaq opened lower on Friday weighed down by Amazon, while Chevron's strong results boosted the Dow.

The Dow Jones industrial average was up 28.35 points, or 0.16 percent, at 18,198.03, the S&P 500 was down 3.36 points, or 0.16 percent, at 2,129.68 and the Nasdaq composite was down 22.15 points, or 0.42 percent, at 5,193.82.

(Reporting by Yashaswini Swamynathan in Bengaluru)