Abstract

Handil field is located in the swampy distributary area of the present day delta of the Mahakam river in East Kalimantan (Indonesia), in the central part of the Kutei Basin.

The anticlinal feature (10.5 km long, 4.5 km wide) was mapped from seismic data in 1973, the discovery well being drilled in April 1974. A W-E fault perpendicular to the axis of the anticline divides the field into two compartments of roughly equivalent area.

Areal closure is 40 km². Vertical closure increases with depth through the hydrocarbon bearing section. Most of the 150 reservoir sands between 450 and 2900 m depth are tidal to fluvial deltaic plain sediments of Middle to Late Miocene age; most of them are oil-bearing with gas-cap. Their types of deposition can be identified: channel fills, tidal bars, etc A high pressure zone is encountered below 2900 m where deeper prospects remain for investigation. More than 70 significant lignitic or coaly markers are used to correlate the sand bodies.

The field has been divided into 6 superimposed zones: from the Lower Zone (2800–2450 m) through to the Very Shallow Zone (850–450 m) corresponding to changes in environment of deposition and/or oil characteristics.

Isobath maps show that the top of the anticline is displaced to the SW by approximately 3 km from deeper horizons to the surface.

In the upper and shallow zones, hydrocarbons are found in the southern compartment only, which itself is divided into smaller blocks by a W-E fault pattern.

Daily production is 160000 barrels, with cumulative production reaching 140 × 10* bbls at the end of 1978.