High Strength Formation and High Overbalance
Applying reactive charge technology to high strength formations in high overbalance environments poses design and operational challenges. The study focuses on the Schooner Field, addressing reservoir pressure, rock strength, and core testing criteria to optimize charge type selection and achieve successful results. Learn from the testing outcomes and proposed field deployment strategies in this comprehensive analysis.
Download Presentation
Please find below an Image/Link to download the presentation.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author.If you encounter any issues during the download, it is possible that the publisher has removed the file from their server.
You are allowed to download the files provided on this website for personal or commercial use, subject to the condition that they are used lawfully. All files are the property of their respective owners.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author.
E N D
Presentation Transcript
An Application of Reactive Charge Technology to High Strength Formation and High Overbalance Environments: Charge Design and Operational Challenges EWAPS-12-2 Paul Lynch David Cockram John Hardesty GeoKey Ltd. Tullow Oil PLC GEODynamics Inc. 1
Agenda Challenges Facing Schooner Field Testing Criteria Test Results Test Conclusions Proposed Way Forward Proposed Field Deployment 2
Schooner Field Schooner Field discovered in 1987 Developed in the mid 1990 s Carboniferous Schooner Formation Fluvial deltaic channel sandstones Initial reservoir pressure 6,564psia Hydrocarbon 51 API Condensate 3
Challenges of Schooner Field Reservoir Pressure - Maximum Overbalance - 3,500psi Rock strength Max UCS - 22,000psi Permeability Min - 2,900psia 1mD 4
Test Criteria Rock selection to match Schooner Identify rock targets to match Permeability Porosity Rock Strength - 10mD 11% - 18,000 - 22,500psi Preliminary Testing Permeability Porosity Rock strength (UCS) - 17,000psi Actual Test Cores Permeability Average porosity - 2.7 mD - 5.1% - 0.29mD - 6.55% 5
Test Criteria Charge Type Selection 4 Gun type with either 23g or 39g system Conventional and Reactive Deep Penetrating charge types Test Conditions to Match Schooner Pore pressure Overburden Wellbore pressure 6,400 psi Overbalance 2,900 psi 12,500psi 3,500 psi 6
Test Results Test Charge PR I Perm Penetration Clear TSP 01 39g Conventional 1.271 0.338 8.900 3.800 TSP 02 23g Reactive 0.977 0.433 7.000 5.000 TSP 03 39g Reactive 1.245 0.272 8.200 6.500 TSP 04 39g Reactive 0.680 0.443 9.600 5.500 TSP 05 39g Reactive 1.285 0.119 8.200 6.000 7
Test Results Difficulty in examining targets due to fracturing occurring when stresses relieved. Plugging existed in all tunnels to some degree Inflow performance did not correlate to clear tunnel length. 8
Test Results Inhomogeneity in target cores affected: Total Depth of Penetration Post perforation flow results 9
Test Results Reactive tunnels appeared to have circumferential fracture along the tunnel length. Fracturing found at the end of the reactive tunnels 10
Test Conclusions CT Scanning Recommended for future testing. Limit on performance of all charges Limits of reactive clean up with high level of overbalance. Reactive charges did still yield better clear tunnel. Radial Flow testing more appropriate? Streamline testing? 11
Proposed Way Forward Utilise 4 39g Gun system to perforate the well. Utilise Reactive charges Utilise a Perf Pill - Conduct Shoot and Pull Operation Pre completion 12
Proposed Improvement Considerations Reduction in level of overbalance? Underbalance? Static Dynamic Employ additional stimulation? Propellant Stimulation Hydraulic Fracturing Acidisation 13
Questions 14
