Two Navy officers were injured early yesterday when a Greek cargo vessel collided with a Navy transport in heavy fog at the mouth of the Chesapeake Bay, Coast Guard officials reported.

Both ships were extensively damaged in the crash, but both remained afloat and proceeded into Norfolk, the nearest port, under their own power, officials said.

Coast Guard spokesman Doak Walker said the Greek ship, the 13,000 ton Starlight, hit the USS Francis Marion amidship at 8:42 a.m. two miles west-morthwest of Cape Henry near the entrance to the Thimble Shoal channel.

According to Walker, the captain of the Starlight, enroute to Charleston from Baltimore harbor, saw the Navy ship come out of dense fog about onethird of a mile ahead of his ship but could not reverse engines quickly enough to avoid a collision.

The two injured officers were standing on the starboard bridgeway when the collision occured and were taken to Portsmounth Naval Hospital by helicopter, Walker said.

Lt. Commander Robert A. Leary, 39, the ship's operation's officer, was listed in satisfactory condition with leg bruises. Lt. Commander Donald C. Miller, 35, the ship's executive officer, sustained serious injuries to his feet and legs and underwent surgery to save a partially severed left foot.

The accident was the second collision at the channel entrance this year, according to Ensign Dennis Haise, inspector with the Coast Guard Marine Safety Office which is conducting an investigation into the incident.

Haise said neither ship was using a pilot familiar with the channels in the area. "With the bad weather, and so many people using the lanes, it's a wonder it doesn't happen more often," he said.

Walker said the collision caused heavy damage to the naval vessel from the main deck upward and tore a 15-by-15-foot hole in the bow of the Starlight.

The Francis Marion was heading into Norfolk after a four-day voyage from New Orleans, where the ship had participated in Mardi Gras festivities.

Commander Jerry Pape, Navy information officer, said both ships were underway when the collision occured.

"Under heavy fog conditions, we assume certain rules of the road were operational," Pape said, "rules like sound and horn signals." Pape said he did not know if the ships were complying with these rules when the accident occurred.

There were no injuries reported on the Greek ship.