Exxon Mobil Corp ( XOM.N ) said on Wednesday its oil drilling and development activities offshore Guyana were unaffected by a weekend incident in which Venezuela’s navy stopped two exploration vessels the company had hired. The logo of Exxon Mobil Corporation is shown on a monitor above the floor of the New York Stock Exchange in New York, December 30, 2015. Standard & Poor’s Ratings Services said on April 26, 2016, it had cut Exxon Mobil Corp’s corporate credit rating to “AA+” from “AAA,” citing the impact of low oil prices. REUTERS/Lucas Jackson/File Photo Venezuela’s navy halted seismic data collection by the boats on Saturday. The governments of each of the two South American neighboring countries said the exploration vessels were in their territorial waters. A century-long border dispute has heated up in recent years as Irving, Texas-based Exxon has discovered more than 5 billion barrels […]