Characterization and Control of Halophilic Sulfate-Reducing and Methanogenic Microbial Communities in Shale Oil and Gas Systems

atmire.migration.oldid6167
dc.contributor.advisorVoordouw, Gerrit
dc.contributor.authorAn, Biwen Annie
dc.contributor.committeememberGieg, Lisa
dc.contributor.committeememberHarrison, Joe
dc.contributor.committeememberMayer, Bernhard
dc.contributor.committeememberMouser, Paula
dc.date.accessioned2017-11-01T20:24:40Z
dc.date.available2017-11-01T20:24:40Z
dc.date.issued2017
dc.date.submitted2017en
dc.description.abstractIn recent years, the oil and gas industry has been revolutionized by the expansion of shale oil and shale gas operations due to the advancement of hydraulic fracturing and high economic benefits compared to other unconventional resources. Several mechanisms have been proposed for the possible roles of microorganisms in shale gas fields. However, there remains a lack of knowledge regarding the key microbial players shared by all shale reservoirs and their involvements in the operations. Three case studies were conducted using samples obtained from various shale oil and shale gas reservoirs on the possibility of reservoir souring, microbiologically influenced corrosion (MIC) and microbially enhanced oil recovery (MEOR) through both culture-dependent and independent approaches. Case study I, for the Bakken shale oil field in Saskatchewan Canada, showed that continuous injection of low salinity source water can alter the microbial and geochemical conditions of the reservoir. There is a dominance of halophilic microbial community in the saline shale formations, in which Halanaerobium can synthesize the substrates used by halophilic sulfate-reducing bacteria (SRB) for sulfate-reduction, and halophilic nitrate-reducing bacteria (NRB) can inhibit the growth of SRB through nitrite production. At low salinity, the microbial community is much more diverse involving Halanaerobium, Desulfovibrio, Thiomicrospira, Dethiosulfatibacter and Arcobacter, with high potential for souring and MIC. In addition, at low salinity, nitrate-mediated souring control cannot be as easily achieved as nitrite is further reduced to N2. Case studies II and III were for the Duvernay shale gas field and Montney shale oil field in Alberta, Canada, which showed high MIC potential involving similar halophilic taxa as found in the Bakken field. Finally, samples from all three case studies indicated higher salinities were associated with higher ammonium concentrations, which is a product of methylotrophic methanogenesis using methylamines. The addition of methylamines in the hydraulic fracturing process can facilitate the possible interactions between the key players identified in all three case studies. Through this work, mitigation and monitoring technologies targeting recurring taxa involved in shale reservoirs on souring and MIC can be developed, which is highly beneficial for the environment and the economy.en_US
dc.identifier.citationAn, B. A. (2017). Characterization and Control of Halophilic Sulfate-Reducing and Methanogenic Microbial Communities in Shale Oil and Gas Systems (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/25261en_US
dc.identifier.doihttp://dx.doi.org/10.11575/PRISM/25261
dc.identifier.urihttp://hdl.handle.net/11023/4233
dc.language.isoeng
dc.publisher.facultyGraduate Studies
dc.publisher.institutionUniversity of Calgaryen
dc.publisher.placeCalgaryen
dc.rightsUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.
dc.subjectMicrobiology
dc.subject.otherEnvironment
dc.subject.otherMicrobiology
dc.subject.otherPetroleum
dc.subject.otherSulfur
dc.subject.otherMethanogenesis
dc.subject.otherCorrosion
dc.titleCharacterization and Control of Halophilic Sulfate-Reducing and Methanogenic Microbial Communities in Shale Oil and Gas Systems
dc.typedoctoral thesis
thesis.degree.disciplineBiological Sciences
thesis.degree.grantorUniversity of Calgary
thesis.degree.nameDoctor of Philosophy (PhD)
ucalgary.item.requestcopytrue
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