Nathan Smith claims the lost gold and silver cargo of a Spanish barquentine that reportedly ran ashore south of Refugio, Texas, in 1822, could be worth $3 billion (£2 billion). Mr Smith, a musician from Los Angeles, said he used Google Earth, an internet site normally used by people wanting to find their own rooftop, to zoom in to a spot north of the Aransas Pass. There, he saw an outline shaped like a shoeprint near an area known as Barkentine Creek, where the vessel was said to have run aground, he said. After consulting experts and visiting the area with a metal detector, he is convinced he has found the ship, now buried under mud. However, the ranch's owners have refused to allow him on to the land and the dispute has gone to federal court in Houston. Documents and photographs of the area have been sealed by order of the court to hide the exact site. However, Mr Smith told an earlier hearing that it is even possible to make out an X marking the spot, which he believes is part of the ship's capstan.
His lawyers say the case, known as Smith vs Abandoned Ship in order further to preserve the secrecy, hinges on whether the spot - a wetlands area - counts as land or as a navigable waterway. If it is the latter, US law allows the first person to find abandoned treasure to ask the federal courts and the US Army Corps of Engineers for permission to retrieve it. If it is deemed to be land, then it belongs to the family of the ranch's late owner, Morgan Dunn O'Connor. However, other legal experts claim the creek is clearly outside any commercial waterway and so, if it is deemed to be in the water, any wreck belongs to the state of Texas. A judge is due to rule on the case next month. Ron Walker, a lawyer for the ranch's owners, told ABC News: "It was offensive that somebody could go on Google Earth, look down and see what they think under the ground...and come in and say I want to dig up your property. They have no proof anything is there and no experience."
Mr Smith, who was inspired to become a treasure hunter by the Hollywood thriller National Treasure, said he has been looking for three years without any luck. He estimates the treasure near Barkentine Creek to be worth $3 billion. The Texas coast is believed to be littered with wrecked ships, but the notoriously muddy waters of the Gulf of Mexico has made treasure hunting particularly difficult there. Mr Smith's site is not far from Matagorda Bay, where an archaeological team discovered a ship belonging to the 17th century French explorer La Salle in 1995, following an on-off search that had lasted 17 years. ( www.telegraph.co.uk )