Print this pageIdentification of Reservoir Palaeo-Petroleum Distributions Using Organic Geochemistry for Understanding Reservoir Filling Histories, Intra-Reservoir Migration and Defining Best Production Units - Case History from the Froy and Lille Froy Fields, Norwegian Continental Shelf
KARLSEN, A. DAG, ABID G. BHULLAR, KRISTINE HOLM, and KRISTIAN BACKER-OWE
Optimising petroleum production from complex structures requires a thorough understanding of intra-reservoir communication. Understanding how petroleum entered a structure and deciphering how the petroleum column underwent subsequent evolutions has proved to be an extremely cost effective strategy capable of providing reservoir geologists with data relevant for planning petroleum production.
This presentation will illustrate the use of organic fingerprinting of reservoired petroleum, extracted from reservoir cores and petroleum inclusions in sandstones from the ELF operated Froy and Lille Froy oil fields - to deduce intra-reservoir communication between sand-bodies or reservoir compartments. The presentation will also address how to evaluate, using petroleum geochemistry, evidences for hydrocarbon flow across faults and potentially sealing beds.
Fluorescent petroleum inclusions in authigenic cements on clastic minerals may form under reservoir conditions, trapping reservoir petroleum as "hermetically sealed" testers which remain unmixed with later arriving petroleum or gas. The intra-reservoir pseudo-three-dimensional distribution of such inclusions from The Froy and Lille Froy oil fields is used to describe the vertical extent of paleo-oil zones in present gas zones, thus aiding the understanding of the traps as dynamic system through time and thereby allowing an evaluation of proposed models for intra-reservoir migration in these neighboring yet different complex structures. The geochemistry is thus used interactively with sediment-geometrical/structural models.
Analysis of the detailed geochemistry (including biomarkers) of petroleum inclusions and core extracts in the two structures has been used to determine filling directions for the oil in place in these structures. Such data is also used to calibrate basin modeling.