Assessing Impacts on Pressure Stabilization and Leasing Acreage for CO₂ Storage Utilizing Oil Migration Concepts

Journal Article · Wed Feb 23 00:00:00 EST 2022 · International Journal of Greenhouse Gas Control

DOI:https://doi.org/10.1016/j.ijggc.2022.103612· OSTI ID:1855989

Ulfah, Melianna ^[1]; Hosseini, Seyyed ^[2]; Hovorka, Susan ^[2]; Bump, Alex ^[2]; Bakhshian, Sahar ^[2]; Dunlap, Dallas ^[2]

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1. Univ. of Texas, Austin, TX (United States); Tetra Tech
2. Bureau of Economic Geology, Austin, TX (United States)

Favorable geological storage for CO₂ has long been pictured as large anticlines with thick sandstones, similar to oil reservoirs in the petroleum system. Unlike oil, however, stored CO₂ does not need to be recoverable, which raises the possibility of using dissolution and residual trapping to augment the capacity of buoyant traps and tap more of the bulk rock volume. The work presented builds on that idea, asking the following question: If we inject CO₂ down to a syncline – analogous to the carrier bed in the petroleum system – how would this injection mechanism impact storage capacity and plume shape, migration, and stabilization? To address this question, we built a reservoir model, based on seismic interpretation of Middle Miocene strata, offshore Galveston, Texas. 3-D seismic and well logs were used to characterize key intervals. Reservoirs chosen for modeling are progradational-aggradational sands with mud intercalation. They have a higher degree of heterogeneity than the more conventional reservoirs commonly targeted for CO₂ storage. Modeling investigated how far the CO₂ plume would migrate under two scenarios: (1) injecting CO₂ at the base of the salt withdrawal basin (syncline scenario) and (2) injecting CO₂ at the base of the structural closure, similar to a common injection well location for EOR purposes (base scenario). For each scenario, we separately simulated injection of 30 MT of CO₂ and 60 MT of CO₂ continuously for 30 years and observe the plume and pressure evolution for 100 years after the injection stops. The simulation shows that injecting the CO₂ into a syncline limits the vertical migration of CO₂, thus making synclinal injection more secure. In the syncline scenario, the geological layer around the injection point is more heterogeneous than the layer in the base scenario; thus, the CO₂ tends to migrate laterally. Additionally, in the syncline scenario, the plume does not even reach the upper part of the anticline, allowing us to safely store an additional amount of CO₂ into the reservoir. Furthermore, the simulation also shows that in the syncline scenario, the times needed for the reservoir to reach its stabilized pressure after the end of injections are faster. To summarize, CO₂ injection at the base of a syncline could provide additional storage, increase the safety of the project from the limited vertical plume migration, and expedite plume stabilization, which could result in the decrease of monitoring frequency as the project runs, thus lowering the operating cost of the project in the long run.

• Research Organization: Univ. of Texas, Austin, TX (United States)
• Sponsoring Organization: USDOE; USDOE Office of Fossil Energy (FE), Clean Coal and Carbon Management
• Grant/Contract Number: FE0031558
• OSTI ID: 1855989
• Alternate ID(s): OSTI ID: 1963286
• Journal Information: International Journal of Greenhouse Gas Control, Journal Name: International Journal of Greenhouse Gas Control Vol. 115; ISSN 1750-5836
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
CO2 storage
Heterogeneity
Leasing acreage
Migration
Plume shape
Plume stabilization
Pressure decay