Handil field is in the swampy distributary area of the present Mahakam River delta in East Kalimantan (Indonesia), in the central part of the Kutei basin.

The anticline features (10.5 km long by 4.5 km wide) was mapped using seismic data in 1973, and the discovery well was drilled in April 1974. A east to west fault, perpendicular to the axis of the anticline, divides the field into two parts of roughly equivalent area.

The area of closure is 40 sq km and vertical closure increases with depth through the hydrocarbon-bearing section. Most of the 150 reservoir sandstones between the depths of 450 and 2,900 m are tidal to fluvial deltaic plain sediments of middle to late Miocene age; most of them are oil bearing with a gas cap. The depositional environments can be identified as channel fills, tidal bars, etc. A high pressure zone is present below 2,900 m where deeper prospects have not yet been drilled.

More than 70 significant lignitic or coaly marker beds are used to correlate the sandstones.

The field has been divided into 6 superimposed zones from the lower zone (2,800 to 2,450 m) through the very shallow zone (850 to 450 m) corresponding to changes in environment of deposition and/or oil characteristics. Isobath maps show a displacement to the southwest by approximately 3 km of the top of the anticline from deeper zones to the surface.

In the upper and shallow zones, hydrocarbons are found in the southern part only, which itself is divided into smaller blocks by a east to west fault pattern.

Daily production is 160,000 bbl of oil with cumulative production reaching 140 million bbl at the end of 1978.