The number of ships underway does not appear unusually large but the number of aircraft carriers in the North Arabian sea is unusual. I am not aware of any list of naval ships on deployment or deployment locations. The only way to derive this information would be to watch the above linked page daily and see who drops off the list after being underway. However, you'd also have to try to ascertain whether a ship was underway to or from port at any given time.

If anyone is aware of any additional sources of information about Naval ship movement, I'd be interested in seeing those.

Ghawar Is Dying
The greatest shortcoming of the human race is our inability to understand the exponential function. - Dr. Albert Bartlett

Maybe a surprise land invasion from Oman's Musandam Peninsula, walking across a floating bridge of US Navy ships? ;-)

The time for games is over?!

U.S. winds up war games in Gulf

The U.S. navy said on Thursday it had ordered an aircraft carrier to the Gulf to replace one of two patrolling the region, as the United States winds down naval war games on Iran's doorstep.

The Nimitz carrier strike group will sail from San Diego for the Gulf on Monday, a navy spokesman told Reuters, to replace the Dwight D. Eisenhower, as tensions mount between Iran and the West over captured British troops and Iran's nuclear programme.

"She (the Nimitz) will deploy to the Gulf region. She is the relief for Eisenhower, who leaves and she replaces her," Lieutenant Commander Jeff Davis said by telephone from Naval Headquarters in Washington.

Strike groups typically include four or five frigates and destroyers and a submarine.

"You are looking at the early part of May that you would have the transition. It would be without any overlap. There is no plan to overlap them at all," he added.

The Eisenhower and fellow carrier John C. Stennis took part in this week's U.S. war games, the largest in Gulf waters since 2003, when the U.S. led an invasion of Iraq.

The drills, which included anti-submarine, anti-surface and mine warfare drills, end on Thursday. For the first time since the Iraq invasion four years ago, two U.S. aircraft carriers were deployed in the Gulf.

Fifth Fleet spokesman Lieutenant-Commander Charlie Brown said there were currently no plans for more.

"We do not expect to have three carriers in the Gulf region ... but we cannot talk about future needs or future operations," he said.

For a list of ships and aircraft carrier strike groups, see:
Massive Deployment of Naval Power directed against Iran

Could be Munifa (sp Manifa?). If I recall correctly, that's heavy, and also happens to be essentially unsellable due to high vanadium content. I admit that's stretching the description "too heavy". But if the intent of the description is that the oil is undesirable, Manifa fits.

Edited to add:

Oops - I was under the impression that Manifa was ready to produce crude (awaiting only completion of specialized refineries to handle the oil) but some quick checks say that's probably not true, because there's field development in parallel with refinery building.

Besides which, it would have been imprudent to develop the field with no feasible market, so my assumption that it had been developed was unrealistic.