By Sarah Young
LONDON, July 23 (Reuters) - Hopes French Guiana hascommercial oil reserves like those of Ghana across the Atlanticsuffered a new blow on Tuesday as a well off the Latin Americancountry's coast came in dry for explorers Tullow Oil andRoyal Dutch/Shell.
Tullow's production in Ghana has helped finance explorationacross Africa and tempted it off the coasts of French Guiana,Suriname and Guyana - to which west Africa was connectedmillions of years ago, and which has similar geology.
Tullow's stock slid 7.7 percent to 1,029 pence on the news.
The dry hole in the GM-ES-4 well is a much smaller setbackfor operator Shell, the world's second largest investor-ownedoil company, and for another big partner Total.
But it follows disappointing drilling results in two otherFrench Guiana wells. The partners will now drill a final well inthe area where they made the Zaedyus 1 oil discovery in 2011before deciding on their future there.
"French Guiana commerciality remains uncertain," said MorganStanley analysts in a research note.
"Whilst it is highly unlikely there is only oneZaedyus-scale discovery in French Guiana, we now expect Tullowto spend time analyzing its current position before progressingfurther."
Tullow also said a well off the coast of Mozambique in theRovuma basin had discovered uncommercial amounts of gas, butthat there was encouraging evidence of the oil it is alsolooking for.
Tullow is partnered with another big international oilcompany, Norway's Statoil, off the coast of Mozambique- a hotspot for gas development.
"The potential for discovering oil in this region remainsafter we encountered wet gas shows in the deeper sidetrack. Wewill integrate this valuable data into our regional model toimprove our chances of unlocking the oil play potential offshoreMozambique," Tullow Exploration Director Angus McCoss said.
In Mozambique, an exploration hot spot after huge gasdiscoveries made in recent years, Tullow said that the firstdeep water well drilled in area 2 found gas but not instandalone commercial quantities.
This year, Tullow has been under pressure to deliverpositive drilling news. Oil finds in Kenya helped deliver aboost to its prospects earlier in July.
Two small British explorers, Wessex Exploration andNorthern Petroleum also own 1.25 percent stakes in thelicence in French Guiana. Their shares retreated 28 percent and6 percent respectively.
