April 17 (Reuters) - Shares in oil companies Tullow Oil , Royal Dutch Shell and Total SA, fell after a well in offshore French Guiana did not find significant hydrocarbons.
Shell, Total, Tullow Oil, Northern Petroleum and Wessex Exploration, which together own the permit to the block, said they have decided to drill further at the well.
Tullow Oil, which was trading down 10 percent, was the biggest percentage loser on the FTSE 100 index.
Shares in Shell and Total were down about 2 percent in midday trading. Shell was taking 7.87 points off the FTSE 100 - the biggest single drag on the index.
Northern Petroleum was down 18 percent, while Wessex plunged 33 percent.
The GM-ES-3 exploration well at the Guyane permit is the second well of a four-well exploration drilling campaign at the project that began in 2012, following oil discovery at the GM-ES-1 well in 2011.
The GM-ES-3 well intersected a 50 metres gross section of oil stained sands and is now targeted to reach a final depth of 6438 meters. (Reporting by Brenton Cordeiro in Bangalore, additional reporting by David Brett in London; Editing by Saumyadeb Chakrabarty)