GEOSTEERING OF TWO HORIZONTAL WELLS IN SOUTH UMM GUDAIR FIELD: A SUCCESSFUL CASE HISTORY

Abstract

The South Umm Gudair (SUG) oil field located in the Neutral zone between Kuwait and Saudi Arabia has produced since 1968 from an active water drive carbonate reservoir of Lower Cretaceous age. The lower zones are homogenous intervals of higher permeability which appear to be sufficiently swept by natural water drive over a period of time. The upper zones of the reservoir have lower permeability, are relatively thin and are bound by tighter intervals that act as possible barriers to the natural water drive system.

Geosteering techniques are now extensively used in oil and gas industry for horizontal wells to produce hydrocarbons from thin reservoirs to maximise recovery, and restricting water-coning problems. Recent advancements in well placement using Geosteering allow successful targetting of low permeability reservoir with great precision which results in exposing more drainage area in the target pay.

The geosteering technique was considered for the first time in joint operation’s SUG field targetting two horizontal wells. Improved well productivity is achieved through optimised well placement. This success has led to a development plan and strategy of additional horizontal drilling locations to maximise recovery of un-swept oil from the low permeability reservoirs. This paper reviews the success of Geosteering in SUG’s two horizontal wells, completed in July 2004.