Petrophysics, carbon dioxide sequestration, and storage potential of Montney Formation’s shale oil and shale gas pools, with implications for enhanced hydrocarbon recovery

Storage of carbon dioxide in depleted shale reservoirs represents a great opportunity to mitigate climate change events by offsetting part of the CO₂ emissions from the energy sector. The Montney Formation is a widely developed, low porosity and permeability unconventional shale oil and gas reservoir in northeastern British Columbia and western Alberta. Due to existing midstream infrastructure, it is an ideal candidate for CO₂ sequestration, which can potentially be coupled with CO₂-enhanced hydrocarbon recovery (EHR). This thesis investigates the potential to store carbon dioxide within representative Montney shale oil and gas pools, and coupling CO₂ sequestration with EHR. The Montney Formation is primarily composed of quartz and dolomite, although their relative abundances are spatially and stratigraphically variable. Clay content (< 20 wt.%) is comprised of exclusively non-swelling clays, and organic matter is found in trace amounts (< 5 wt.%). Exposure to supercritical CO₂-rich water has a negligible impact on mineral abundances, with only notable changes in calcite and dolomite wt.%. Apparent supercritical CO₂ matrix permeability, ranging between 3.45×10⁻⁴ to 4.07×10⁻² mD, is greater than the apparent gas and liquid CO₂ permeabilities. The higher apparent matrix permeability to supercritical CO₂ compared to the gas or liquid phase is attributed to the properties of the supercritical phase and the higher molecular kinetic energy, which promotes slip flow on the pore walls. The low permeability of the Montney Formation, coupled with the high capillary entry pressure, ensures that the injected CO₂ will be contained within the formation with insignificant leakage risks. Carbon dioxide storage capacities vary among investigated Montney pools. The Northern Montney pool has a significant storage capacity but exhibits poor reservoir properties for CO₂ storage compared to the Kakwa and Waskahigan Montney pools. Exploiting CO₂ injection for enhanced hydrocarbon recovery provides an opportunity to support more carbon-neutral hydrocarbon production with subsequent CO₂ storage. Supercritical CO₂ and a propane/butane (C₃/C₄) hydrocarbon mixture prove effective in recovering liquid hydrocarbons, with the C₃/C₄ mixture outperforming CO₂ at early Huff and Puff cycles and at heavy hydrocarbon mobilization. Supercritical CO₂ remains a viable recovery agent, recovering between 70 and 90% of the hydrocarbons in place.Science, Faculty ofEarth, Ocean and Atmospheric Sciences, Department ofGraduat

Geology and Geochemistry of the Hydrocarbon Compositional Changes in the Triassic Montney Formation, Western Canada

The geochemistry of produced fluids has been investigated in the Triassic Montney Formation in the Western Canadian Sedimentary Basin (WCSB). Understanding the geochemistry of produced fluids is a valuable tool in the exploration and development of a complex petroleum system such as the Montney Formation. The petroleum system changes from in situ unconventional reservoirs in the west to more conventional reservoirs that contain migrated hydrocarbons to the east. The workflow of basin modeling and mapping of isomer ratio calculations for butane and pentane as well as the mapping of excess methane percentage was used to highlight areas of gas compositional changes in the Montney Formation play area. This workflow shows the migration of hydrocarbons from deeper, more mature areas to less mature areas in the east through discrete pathways. Methane has migrated along structural elements such as the Fort St. John Graben as well as areas that have seen changes in higher permeability lithologies (i.e., well 14-23-74-8W6M). Excess methane percentage calculations highlight changes due to fluid mixing from hydrocarbon migration. The regional maturation polynomial regression line was used to determine the gas dryness percentage for each well on the basis of its maturation level determined by the butane isomer ratio. The deviation from the calculated gas dryness according to the regression was determined as an excess methane percentage. The British Columbia (BC) Montney play appears to have hydrocarbon compositions that reflect an in situ generation, while the Montney play in Alberta (AB) has a higher proportion of its hydrocarbon volumes from migrated hydrocarbons. The workflow provides a better understanding of the hydrocarbon system to optimize operations and increase production efficiency. Understanding the distribution of gas compositions within a play area will provide key information on the liquid and gas phases present and an understanding of how gas composition may change over the well life, as well as helping to maximize liquid recovery during well operations.Science, Faculty ofNon UBCEarth, Ocean and Atmospheric Sciences, Department ofReviewedFacultyResearcherGraduat

Treatment of metastatic melanoma: a multidisciplinary approach

The prognosis of stage IV metastatic melanoma is poor. An overall 1-year survival of 25.5% and a median survival of 6.2 months were reported without any significant improvement during the last 30 years before the introduction of new drugs (immune checkpoint inhibitors and targeted therapies) which completely modified the therapeutic approach and induced an overwhelming improvement on the survival rates of these patients. This review will analyze the therapeutic tools available for the treatment of patients with metastatic melanoma, including adjuvant interferon and locoregional therapies (surgery, radiotherapy and electrochemotherapy) and will mainly focus on the presentation of results obtained by the new treatments (checkpoint inhibitors and targeted therapies)

Phenotypical characterization of circulating cell subsets in pyoderma gangrenosum patients: The experience of the Italian immuno-pathology group

Background No data are available as to the phenotype of circulating lymphocyte subsets in pyoderma gangrenosum (PG). Aim To analyse the expression of different chemokine receptors associated to T-helper (Th)1 (CCR5), Th2 (CCR4) and Th17 (CCR6), as well as the regulatory T-cell subset (Treg) and dendritic cell polarization in the blood of newly diagnosed untreated PG patients. Materials and methods Multi-parameter flow cytometry was performed on blood samples from 10 PG patients collected at first diagnosis among centres belonging to the Italian Immuno-pathology Group. Blood samples from 10 age- and sex-matched healthy controls (HC) were used as controls. Results PG patients are characterized by an over-expression in the blood of the CD4+CCR5+ and CD4+CCR6+ and a down-regulation of CD4+CCR4+ counts with respect to healthy subjects. Moreover, they show increased levels of myeloid derived dendritic cells type1 and reduced levels of the Treg CD4+CD25highFOXP3+ subset. Conclusions The pattern of chemokine expression argues in favour of a Th1 (CCR5+) and Th17 (CCR6+) polarization with a down-regulation of Th2 (CCR4+)