SLAC National Accelerator Laboratory Coupling of Geochemical and Geomechanical Processes in the Manipulation of Fracture Systems in Subsurface Formations Used for Carbon Sequestration

 

Laser focused on shale sample
Laser focused on shale sample
Performer: 
ORNL - Oak Ridge National Laboratory
Website:  SLAC National Accelerator Laboratory
Award Number:  FWP-100249
Project Duration:  09/01/2015 – 03/31/2017
Total Award Value:  $150,000
DOE Share:  $150,000
Performer Share:  $0
Technology Area:  Geologic Storage
Key Technology:  GS: Geochemical Impacts
Location:  Oak Ridge, Tennessee

Project Description

The low primary and secondary porosity of shales retards flow of CO2 and CO2-bearing fluids, making this rock type desirable as a cap rock formation above reservoirs targeted for geological carbon storage. Potential contributors to CO2 leakage through cap rock formations include: (i) poorly sealed or improperly decommissioned wells, and (ii) structural migration paths in cap rock itself (dissolution channels, fractures). This project is performing a feasibility study to investigate the scientific basis of laser-assisted drilling techniques to enhance both the sealing of cap rock around well completions and down-well manipulation techniques for control of cap rock migration paths. A number of representative cap rock samples are being screened to assess the effects of laser treatment on porosity, mineralogy, vitrification, and fracture surface chemistry.

SLAC and FORO Energy have completed a detailed experimental design and initial characterization of untreated Green River and Marcellus shale samples. The surfaces and porosity of selected samples were characterized to determine the surface chemistry, mineralogy, and porosity of each sample, prior to any laser treatment, to set a baseline for comparison. Samples exposed to laser fluence at FORO are undergoing post-treatment characterization at SLAC to determine how exposure affects morphology and if it is feasible to weld shales.

Project Benefits

Advanced techniques that provide the capability to rapidly and inexpensively seal migration paths during installation of new well completions and decommissioning of old wells would provide the opportunity for a transformational improvement of carbon storage practices. Additionally, this project focuses on control and manipulation approaches to subsurface porosity, one of the four pillars of the SubTER program.

Contact Information

Federal Project Manager 
Andrea Dunn: andrea.dunn@netl.doe.gov
Technology Manager 
Traci Rodosta: traci.rodosta@netl.doe.gov
Principal Investigator 
Mark Hartney: mhartney@slac.stanford.edu
 

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