Multilayer Map Based Hydrocarbon Modelling, a Sensitivity Study from a Frontier Area, Norwegian Continental Shelf

By

Martin Hamborg¹, Tomas Kjennerud¹, Reinert Seland², Oivind Lonne³, Oyvind Sylta¹

(1) SINTEF Petroleum Research, Trondheim, Norway (2) Aker Geo Petroleum Services, Stavanger, Norway (3) GEO-42 AS, Stavanger, Norway

 A multilayer migration technique is used to model hydrocarbon systems where the oil and gas migration occurs vertically upwards within mudrock sequences and faults. Lateral hydrocarbon migration occurs within well-defined carriers.

This presentation aims to highlight hydrocarbon charge risks based on a complex geological model in a frontier area. The geological model consists of 16 interpreted horizons and 5 constructed surfaces. Four source rocks and six carriers are also incorporated in the map based computer model. Maturation and expulsion modelling are performed on the four source rocks. The temperature model used for maturation and expulsion is calibrated with temperature data, and modelled maturity against meassured vitrinite reflectance. The source rocks are assumed to charge directly three of six carrier beds, all in different stratigraphic positions. Hydraulic leakage and capillary leakage from hydrocarbon traps are presumed to be a vertical sourcing mechanism to above lying carriers.

The prospectivety is assessed based on maximum, minimum and most likely cases for each of the source rocks’ richness and extent. The same classification is used on the lateral extent of the carriers. Sensitivity to vertical trap-leakage rates is assessed both for hydraulic and capillary leakage. The effects of detailed reconstruction of palaeo-water depth on trap configurations are explored for six timesteps within the last 2.7 million years. The trapped hydrocarbons are calibrated against known fields and a match with hydrocarbon phases in the traps is obtained.