The Nitrogen, Sulphur, Oxygen (NSO)-containing fraction of petroleum, termed resins and asphaltenes, is highly complex. NSO-compounds vary in polarity and are partitioned between aqueous and organic phases as well as mineral surfaces. They constitute the heavy fractions of petroleum and help govern its bulk physical properties, such as viscosity and API Gravity.

Project Goals

• Expand our understanding of NSO compound geochemistry and its effect on fluid properties (1) along the pathway from source to carrier to reservoir to production line in conventional petroleum systems and (2) from dispersed petroleum to produced fluids in unconventional systems.
• Trace differently polar structural moieties from the kerogen and retained heavy bitumen to in-reservoir and produced polar and aromatic hydrocarbon fractions: Apply FT-ICR-MS in 3 ionization modes to produced oils, reservoir core and source rock extracts.
• Unravel fractionation effects due to rock-fluid interactions as well as influences and interdependencies caused by facies and maturity variations by integrating GC-FID and GC-MS results.

Conventional petroleum systems offshore Norway & Brazil: Oils and reservoir core extracts from carbonate and clastic carrier and reservoir rocks help understanding the influence of lithology on migration fractionation of oils from marine and lacustrine source rocks in the North Sea Central Graben (Mandal/Farsund Formations) and in the Brazilian Potiguar Basin.

Unconventional petroleum systems: Lower 48 US shale plays: Produced oils and source/reservoir extracts from Wolfcamp, Eagle Ford, and Niobrara shale plays will be investigated to unravel the impact of NSO geochemistry on total producible oil-in-place as a function of source, lithology and maturity. Thermal extracts help to predict the effect of fractionation on the NSO fraction during production.

Participants

• Volker Ziegs (GFZ)
• Dr. Nicolaj Mahlstedt (GEOS4)
• Prof. Brian Horsfield (GEOS4)
• Dr. Stefanie Pötz (GFZ) 

Funding

IPP (Industry Partnership Programmme):

• Aker BP (Norway)
• Petrobras (Brazil)
• ConocoPhilips (U.S.)
• Encana (U.S.)