ABSTRACT

The continuous depletion of oil and gas deposits in shallow waters has made it necessary to exploit reserves in deep waters (500-1500 m) and ultra deep waters (>1500 m) in order to ensure future supply. In deep waters it is not feasible to use fixed drilling and production platforms and instead floating structures are employed. Associated with the move to deeper waters, has been a transition from catenary to taut and semi-taut leg mooring systems (Eltaher et al. 2003). Taut and semi-taut mooring lines are designed to have high angles of inclination (40-45◦) with the mudline and thus require anchors that can sustain significant vertical components of load (Ehlers et al. 2004).