CO2 Seal and Bypass - COPASS

COPASS – CO2 Seal and Bypass Project. The Bartlett Fault, Utah. The fault juxtaposes the Entrada and Morrison formations, and has partially sealed in the CO2-charged groundwater that migrated through the porous sandstones of the Entrada Formation. Photo/Illustration: Ivar Midtkandal

About the project

Technology related to geological sequestration of CO2 provide a significant means for mitigating global emissions - this in spite of public skepticism and a shortage of incentives to develop CO2 storage into a profitable venture. Most existing sequestration sites are generally small and have not been operational for sufficient time to fully forecast and assess leakage scenarios of laterally extensive reservoirs on the time scales relevant for subsurface CO2 storage (> 10 kY). Thus the study of exhumed reservoirs showing evidence of CO2 accumulation in geological history and leakage processes may offer an important supplement to our knowledge on relevant spatial and temporal scales.

Reservoirs in the North Sea are matured for CO2 storage; however, key questions around plume migration mechanisms and pressure linked to site integrity have been raised for both the Sleiper and Snøhvit cases, as well as for the Longyearbyen CO2 lab and Svelvik pilots. It is need of in-depth analysis of CO2 flow systems with bearing on the forecasting reliability of reservoir models. It will be fundamental for future North Sea CO2 storage sites to improve the understanding of storage efficiency, dynamics of injectivity and pressure linked to CO2-driven reactions, and pressure-driven reactivation of faults and fractures jeopardizing storage integrity.

In order to fully understand which mechanisms and geological parameters govern both the localization of leakage points through intra-reservoir flow baffles and trap-confining seals, our field observations will be implemented in 3D geological models which form the basis for conducting fluid flow simulations.

Objectives

We will explore CO2 plumbing systems of reservoirs and caprocks by integrating observations from actively leaking and former, exhumed reservoir-seal systems employing field, laboratory and reservoir modelling studies.

We aim to implement observed flow and leakage patterns combined with observed diagenetic status and rock strength assessments in 3D simulation models. Our ultimate goal is to simulate flow and critical pressure based on rock and fault rock mechanics in a workflow that allow fault and fracture venting similar to what is currently observed in the Little Grand Wash Fault CO2 leakage scenario.

The work is organized in five work packages: 1) Rock properties (Two study objects Little Grand Wash Fault and Humbug Flats); 2) Diagenetic effects; 3) Geomechanics; 4) Reservoir modelling and simulation; 5) Education and outreach.

Background

In the COPASS project we focus on two study areas, both with natural subsurface with particular relevance to CO2 storage studies, and with a unique and detailed insight into flow of CO2 in subsurface reservoirs. 

The two case study areas ares in Utah, USA; both the Little Grand Wash Fault and the - Humbug Flats of the NE San Rafael Swell will offer unique datasets which can significantly improve our ability to forecast leakage from subsurface CO2 storage sites.

Financing

The COPASS project are granted financing from the Norwegian Research Council and the VISTA programme/STATOIL. This project is also linked to other ongoing research activity in Norway and the USA, and there is a close association toward other Norwegian and US-based federal and private funds.

Project duration of the COPASS project is from January 2015, with a 4 years frame ending in 2018.

Cooperation

• Department of Geosciences, University of Oslo
• Western State Colorado University - WSCU
• USU
• Uni Research CIPR
• Colorado School of Mines 
• NGI