Divers examining the sunken battleship USS Arizona in the murky waters of Pearl Harbor have found that it was virtually blown in two and that its 14-inch armor plating is "curled like lettuce leaves," according to reports from the first close survey of the scene since World War II.

A 100-foot gap in the heavily armored ship was made by the single most destructive shot fired during the Japanese attack on Pearl Harbor. That was an 1,800-pound bomb that penetrated the Arizona's deck and struck fuel and ammunition caches, creating an explosion heard across the island of Oahu in the early morning of Dec. 7, 1941.

According to the Navy, more than 1,000 sailors and Marines remain entombed in the ship, and about 170 bodies and other remains have been recovered.

Half of all of the deaths in the attack on Pearl Harbor occurred on the Arizona, according to Donald Goldstein, co-author of "At Dawn We Slept," a recent account of the attack.

The current diving expedition has begun to draw a detailed, three-dimensional picture of the great warship as it lies in 20 feet of silt at the harbor bottom and also to answer questions about the sinking of the 608-foot ship.

National Park Service and Navy divers have described the scene in the shallow, 30- to 40-foot waters as "eerie."

The Arizona's forward guns are separated from the bow by a 100-foot mass of debris and twisted armor that once was the forward deck.

"To see the destruction to the forward part of the ship is inspiring and scary. The forces that tore it apart were truly massive," said John Martini, chief ranger at the USS Arizona Memorial in the harbor above the ship.

Divers report that beyond its midsection the ship remains much as when it went down. Hatches supposed to be closed during battle are open, and a fire hose being uncoiled lies where it was dropped on deck. Poles that held sun awnings remain up, and silverware and china from the crew's mess are scattered on deck amidships.

Between glass portholes and their covers, shut during the attack, is air trapped on that December morning, divers said.

The divers are probing the wreck daily, videotaping what can be seen in the 10-foot visibility and laying a grid of white nylon lines to facilitate accurate mapping of the ship.

The chief purpose of the expedition is determining the ship's exact condition to aid future preservation work and to resolve questions about the sinking of the only major warship lost in the attack and never returned to battle.

The two-hour attack on Pearl Harbor began about 8 a.m. as the Navy base was awakening for a normally quiet Sunday morning. The Arizona, one of seven battleships aligned neatly along Ford Island in the middle of the harbor, was preparing to go to sea, and was loaded with fuel and more than 1 million pounds of explosives.

Sailors and Marines were aboard, some preparing for shore leave, some for church, and one man was being held on charges made on a nearby ship with no brig. He was still locked up when the ship went down.

The Arizona's band had won second place in a contest the night before, and its members were allowed to sleep late. All of them died.

On a nearby ship, the customary raising of the colors was under way, and its band played the Star Spangled Banner, continuing through the bombing and red glare as waves of Japanese planes pounded the area and the Arizona began sinking, accordingto a Park Service spokesman.

According to the Navy, a Japanese bomber of the "Kate" type, somewhat larger than the famous "Zero" fighter plane and equipped with a single 1,800-pound bomb, scored a direct hit on the Arizona's deck.

The bomb, a Japanese Navy artillery shell redesigned to include flight fins to pierce ship's armor before exploding, plunged through the foredeck and exploded in a fuel storage room. Fire flared there for only a few seconds before the 1 million pounds of explosives ignited with an enormous blast in a nearby compartment.

Within eight minutes of the hit, the Arizona sank.

Some reports of the time said the bomb had gone directly down the ship's funnel.

"All these years, survivors from the battleship and a repair ship tied up alongside her at the time have been adamant in insisting that the Arizona was also hit by a torpedo, although the official report doesn't mention a torpedo," said Gary Cummins, superintendent of the Arizona Memorial and a project diver.

Now the bomb's point of impact is beyond doubt, and the massive damage reported by the divers affirms the Navy's conclusion that one bomb sank the ship. No torpedo hole or damage was found on the side of the ship that some have thought was hit.

Martini said a torpedo may have struck on the port side in an area now obliterated by the bomb hit, but probably would have done little damage. Other ships at Pearl Harbor took as many as seven torpedo hits but were repaired.

One lingering question deals with the ship's oil, which began leaking on impact and has leaked slowly ever since.

According to the Park Service, one drop of oil, about the size of a jellybean, surfaces about every 20 seconds, creating a constant oil slick in the harbor. The divers have found that the oil is gurgling through the deck between the stern and midsection.

Park Service divers said they think that oil trapped in the storage compartments between the ship's double hulls is making its way along passages, up ladders and through a small crack in the deck.

The divers do not plan to enter the ship because of the danger involved and because the Arizona has been designated a national cemetery and entering it could be thought of as desecrating a tomb.

The expedition is being sponsored by the Arizona Museum Memorial Association, which has collected funds from sales at the site's museum shop. The memorial, under National Park Service jurisdiction since 1981, attracts about 1.2 million visitors a year.