Major U.S. stock indexes opened flat to modestly higher Wednesday as earnings season unofficially kicked off with results from Wall Street giants JPMorgan Chase & Co. /zigman2/quotes/205971034/composite JPM -3.01% and BlackRock Inc. /zigman2/quotes/207946232/composite BLK -3.12% , as well as Delta Air Lines Inc. /zigman2/quotes/200327741/composite DAL -8.34% . The Dow Jones Industrial Average /zigman2/quotes/210598065/realtime DJIA -2.53% rose 30 points, or 0.1%, to 34,408, while the S&P 500 /zigman2/quotes/210599714/realtime SPX -2.27% edged up 0.2% to 4,360. The Nasdaq Composite /zigman2/quotes/210598365/realtime COMP -2.23% advanced 0.4% to 14,531. JPMorgan Chase shares were down 0.8% in the early going, while BlackRock shares jumped 3%. Delta shares gave up 2.8%.