Part_D_3.pdf

CO2 Sequestration and Storage Quiz Answers 1. What is the theoretical storage efficiency for regional storage assessments for saline aquifers? A. 5% B. 10% C. 20% D. 30% Answer: 5% (A) Theoretical storage efficiencies of ca. 5% are assumed for regional storage assessments for saline aquifers. 2. Whi...

CO2 Sequestration and Storage Quiz Answers 1. What is the theoretical storage efficiency for regional storage assessments for saline aquifers? A. 5% B. 10% C. 20% D. 30% Answer: 5% (A) Theoretical storage efficiencies of ca. 5% are assumed for regional storage assessments for saline aquifers. 2. Which type of CO2 storage involves the production of blue hydrogen from natural gas with carbon capture? A. Ocean Storage B. Enhanced Oil Recovery (EOR) C. Disused gas fields storage D. Mineral carbonation Answer: Disused gas fields storage (C) The production of blue hydrogen from natural gas with carbon capture is associated with CO2 storage in disused gas fields. 3. What is the greatest leakage risk for sequestration in depleted hydrocarbon fields? A. Inefficient injection techniques B. Integrity of existing wells C. Corrosion of storage containers D. Inadequate geological characteristics Answer: Integrity of existing wells (B) The greatest leakage risk for sequestration in depleted hydrocarbon fields is often the integrity of existing wells. 4. Where will CO2 be injected in the Northern Lights CCS project for sequestration? A. 20 km south of the Troll Structure B. In the Troll Formation C. At the Troll Structure D. 20 km north of the Troll Structure Answer: 20 km south of the Troll Structure (A) CO2 will be injected ca. 20 km south of the Troll Structure in the underlying Cock and Johansen Formations at a depth of ca. 2700m. 5. What is the first exploitation license for CO2 storage awarded to Equinor, Shell, and Total? A. Northern Lights CCS project B. Sleipner License EL001 C. Garn and Ile study EL001 D. Depleted Frigg Gas Reservoir Answer: Northern Lights CCS project (A) The first exploitation license for CO2 storage was awarded to Equinor, Shell, and Total in the Northern Lights CCS project. 6. What is the depth at which CO2 will be injected in the Northern Lights CCS project? A. 1500m B. 2000m C. 2500m D. 2700m Answer: 2700m (D) CO2 will be injected ca. 20 km south of the Troll Structure in the underlying Cock and Johansen Formations at a depth of ca. 2700m. 7. What is the theoretical storage capacity for ocean storage of CO2? A. Lake type B. Mineral carbonation C. Subsurface mineralisation D. Dissolution type Answer: Dissolution type (D) Ocean storage falls under the theoretical storage capacity for dissolution type of CO2 storage. 8. What is the main reason for low CO2 storage efficiency? A. High CO2 viscosity B. Low permeability heterogeneity C. Structural trap limitations D. Unfavorable CO2 - water mobility ratio Answer: Unfavorable CO2 - water mobility ratio (D) Low CO2 storage efficiency is due to an unfavorable CO2 - water mobility ratio (low CO2 viscosity). 9. What is the primary risk to well integrity in sequestration in depleted hydrocarbon fields? A. Geological instability B. Inadequate well depth C. Fractures in the cement D. Corrosion by carbonic acid Answer: Corrosion by carbonic acid (D) Carbonic acid (CO2 dissolved in water) is very corrosive to materials such as cement and steel, posing a risk to well integrity. 10. Where is the HyNet Project for blue hydrogen production and CO2 storage located? A. Norwegian Sea B. Mediterranean Sea C. North Sea D. East Irish Sea Basin Answer: East Irish Sea Basin (D) The HyNet Project for blue hydrogen production and CO2 storage is located in the East Irish Sea Basin. 11. What are the trapping mechanisms for CO2 sequestration in saline aquifers? A. Structural/stratigraphic trapping, residual trapping, solubility trapping, mineral trapping B. Biological trapping, mechanical trapping, electrical trapping, magnetic trapping C. Pressure trapping, temperature trapping, capillary trapping, chemical trapping D. Physical trapping, chemical trapping, biological trapping, mechanical trapping Answer: Structural/stratigraphic trapping, residual trapping, solubility trapping, mineral trapping (A) The trapping mechanisms for CO2 sequestration in saline aquifers include structural/stratigraphic trapping, residual trapping, solubility trapping, and mineral trapping. 12. Which project is associated with CO2 storage in depleted oil reservoirs? A. GeoNet Project B. HyNet Project C. CarbonNet Project D. EcoNet Project Answer: HyNet Project (B) The HyNet Project is associated with CO2 storage in depleted oil reservoirs. 13. What is the injectivity index a function of? A. Reservoir pressure, well head pressure, flow rate B. Capillary seal failure, fracture seal failure, CO2 plume migration C. Structural trapping, residual trapping, solubility trapping, mineral trapping D. Formation permeability, fluid viscosity, thickness of permeable interval Answer: Formation permeability, fluid viscosity, thickness of permeable interval (D) The injectivity index is a function of the formation permeability, the fluid viscosity, and the thickness of the permeable interval. 14. What is needed for structural and stratigraphic trapping to occur? A. Well head, flow rate, reservoir pressure B. Pressure build-up, CO2 injector, depth C. Reservoir rock, trap, seal D. Anticline, pinchout, unconformity Answer: Reservoir rock, trap, seal (C) For structural and stratigraphic trapping to occur, a reservoir rock, a trap, and a seal are needed. 15. What is the purpose of CO2 plume migration and trapping mechanisms in saline aquifers? A. To increase the pressure build-up in CO2 accumulation B. To enhance the mineral trapping process C. To prevent CO2 from escaping the storage site D. To facilitate the capillary seal failure Answer: To prevent CO2 from escaping the storage site (C) The purpose of CO2 plume migration and trapping mechanisms in saline aquifers is to prevent CO2 from escaping the storage site. 16. What are the examples of CO2 sequestration modeling mentioned in the text? A. The Val Verde, the HyNet, and the Global Status of CCS B. The Utsira Formation, the Garn and Ile formations C. The Norwegian Continental Shelf, the Global CCS Institute, and the NPD CO2 Storage Atlas D. The Sleipner, the Modena, and the Northern Lights Answer: The Utsira Formation, the Garn and Ile formations (B) Examples of CO2 sequestration modeling mentioned in the text include the Utsira Formation, the Garn and Ile formations. 17. Which geological storage was operational in 1972? A. Northern Lights B. Val Verde USA C. Sleipner, Norway D. Utsira Formation Answer: Val Verde USA (B) The Val Verde USA geological storage was operational in 1972. 18. What is the purpose of CO2 storage inventories? A. To analyze the capillary seal failure in saline aquifers B. To monitor the pressure build-up in CO2 accumulation C. To estimate the potential for enhanced oil recovery D. To track the amount of CO2 sequestered over time Answer: To track the amount of CO2 sequestered over time (D) The purpose of CO2 storage inventories is to track the amount of CO2 sequestered over time. 19. What does CO2 injector pressure represent in the context of CO2 accumulation? A. Pressure increase required to inject at the target rate B. Flow rate of CO2 injection C. Pressure build-up at the well head D. Pressure depth in the CO2 reservoir Answer: Pressure increase required to inject at the target rate (A) CO2 injector pressure represents the pressure increase required to inject at the target rate in the context of CO2 accumulation. 20. What type of trapping mechanism involves the physical entrapment of CO2 in the pore spaces of the rock? A. Structural trapping B. Solubility trapping C. Capillary seal failure D. Residual trapping Answer: Residual trapping (D) Residual trapping involves the physical entrapment of CO2 in the pore spaces of the rock. 21. What can lead to top-seal failure and leakage in CO2 accumulation? A. Low injection rate or CO2 column thickness B. High injection rate or low CO2 column thickness C. Low injection rate or high CO2 column thickness D. High injection rate or CO2 column thickness Answer: High injection rate or CO2 column thickness (D) High injection rate or CO2 column thickness can lead to pressure build-up in CO2 accumulation, causing top-seal failure and leakage. 22. What influences capillary pressure in CO2 accumulation and can cause leakage if it matches the capillary threshold pressure of the seal? A. CO2 column thickness B. Seal thickness C. Fluid density contrast D. Injection rate Answer: Fluid density contrast (C) Capillary pressure in CO2 accumulation is influenced by fluid density contrast and can cause leakage if it matches the capillary threshold pressure of the seal. 23. What is the process where CO2 dissolves in formation water, leading to trapping? A. Stratigraphic trapping B. Structural trapping C. Solubility trapping D. Residual trapping Answer: Solubility trapping (C) Solubility trapping occurs as CO2 dissolves in formation water, leading to trapping. 24. Which project has been sequestering 1 million tonnes of CO2 per year since 1996? A. The Sleipner CO2 Storage Project B. The Garn and Ile Formation Project C. The CO2 Sequestration Simulation Project D. The Utsira Formation Project Answer: The Sleipner CO2 Storage Project (A) The Sleipner CO2 Storage Project has been sequestering 1 million tonnes of CO2 per year since 1996. 25. Which formation consists of 200m thick sands capped by mudstone and has been effective in storing CO2 without evidence of leakage? A. Garn Formation B. Sleipner Formation C. Utsira Formation D. Ile Formation Answer: Utsira Formation (C) The Utsira Formation consists of 200m thick sands capped by mudstone and has been effective in storing CO2 without evidence of leakage. 26. What have time-lapse seismic sections shown on Sleipner? A. No migration of the CO2 plume B. Rapid vertical migration and lateral spreading of the CO2 plume C. Precipitation of new calcite minerals D. Slow vertical migration and lateral spreading of the CO2 plume Answer: Rapid vertical migration and lateral spreading of the CO2 plume (B) Time-lapse seismic sections have shown rapid vertical migration and lateral spreading of the CO2 plume on Sleipner. 27. What does the injection simulation in the Utsira Formation suggest is possible in terms of CO2 injection? A. Up to 300 million tCO2 injection B. Up to 400 million tCO2 injection C. Up to 200 million tCO2 injection D. Up to 100 million tCO2 injection Answer: Up to 200 million tCO2 injection (C) Injection simulation in the Utsira Formation suggests up to 200 million tCO2 injection is possible, with migration and accumulation in surrounding structures over 8000 years. 28. What indicates that about 400 million tons of CO2 can be stored in the Garn and Ile formations with an acceptable pressure increase using 4 injection wells? A. Fluid density contrast B. Modelling CO2 sequestration C. Injection rate analysis D. Time-lapse seismic sections Answer: Modelling CO2 sequestration (B) Modelling CO2 sequestration in the Garn and Ile formations indicates that about 400 million tons of CO2 can be stored with an acceptable pressure increase using 4 injection wells. 29. What type of aquifers are the Garn and Ile formations? A. Good quality, thick aquifers dipping about 2° towards the shore B. Good quality, thick aquifers dipping about 5° towards the shore C. Good quality, thick aquifers dipping about 2° away from the shore D. Low quality, thin aquifers dipping about 2° towards the shore Answer: Good quality, thick aquifers dipping about 2° towards the shore (A) The Garn and Ile formations are good quality, thick aquifers dipping about 2° towards the shore, suitable for CO2 storage. 30. What can be yielded by injection into the Garn and Ile aquifer over 50 years with 4 injection wells? A. 6 million tons/year B. 8 million tons/year C. 10 million tons/year D. 4 million tons/year Answer: 8 million tons/year (B) Injection into the Garn and Ile aquifer can yield 8 million tons/year over 50 years, requiring 4 injection wells and resulting in an acceptable pressure increase.