Cairn spudded the well targeting the stacked fan structure using the fifth generation rig Cajun Express.
The well is the first in a two-well programme in Senegalese waters, and the first offshore well to be drilled in the area in more than 20 years.
The well will be followed immediately by a second well.
Joint venture partner Far secured funding for the two exploration wells based on its farm-out deal with Cairn’s wholly-owned subsidiary Capricorn Senegal.
Far managing director Cath Norman said the company had high hopes for the two wells.
“Success in either of these wells opens the door to a large play fairway of follow on drill targets which are very significant for Far,” she said.
Cairn Energy holds a 40% interest and operatorship with Far holds a 15% interest. The rest of the interest lies with ConocoPhillips (35%) and Petrosen (10%).
Fan-1 is an exploration well and even if successful, will not be completed as a commercial production well.
If the well is successful, the joint venture may conduct more drilling and evaluation activities.