Developing a full field geological model with subsequent reservoir numerical simulation on the Krafla field

Abstract

The Krafla field is newly discovered in production license PL 272/035 which is located in the North Sea where Statoil is the operator and Det Norske Oljeselskap is one of the partners. Exploration wells are drilled on the structure where the aim is to prove existence of commercial hydrocarbons in the Tarbert Formation and to collect sufficient data needed to assess the development of the prospect. Development solutions are evaluated and production platforms nearby is able to assist in producing the field.

A full field geological model is developed with petrophysical data provided as input from the exploration wells. A grid is constructed in Petrel with reservoir properties and computational saturation functions simulated throughout the grid. The geological model are imported into Eclipse are the remaining initialization are performed.

A total of 5 scenarios are initialized and simulated by the use of reservoir numerical simulation, where total fluid production and rate is evaluated in addition to gas oil ratio and bottom hole pressure. The scenarios consisted of differing number and types of wells, perforation heights, well placement and water injection.

The first scenario is considered the base case where the well placement, number and types of wells are initialized by knowledge from similar structures as the Krafla field and from development strategies performed on earlier basis. The previous two scenarios are observing the difference by the addition and removal of an oil producer on Krafla Main which also contained a water injection well. The remaining two scenarios are performed on Krafla West are the difference in providing a vertical well in relation to a horizontal well is observed.

As the base case only represents the base wireline log interpretation and one set of maps, there are a significant uncertainty and source of errors. However, the model will be a basis for further simulations and detailed studies.