School of Civil and Environmental Engineering

Ph.D. Thesis Defense Announcement

Geomechanical Properties of Natural Sediments with Tetrahydrofuran Hydrate

By Imgenur Tepecik

Advisor:

Dr. Sheng Dai (CEE)

Committee Members:  Dr. J. David Frost (CEE), Dr. J. Carlos Santamarina (CEE), Dr. William F. Waite (USGS), Dr. Yongkoo Seol (NETL)

Date and Time:  April, 2, 2025. 11:30am – 1:30pm

Location: SEB 122

Teams: Virtual Link

Methane hydrate has the potential to be a new energy resource due to its large reserve and wide distribution all over the world. Safe removal of methane gas from the subsurface also decreases the risk of uncontrolled release of this greenhouse gas into the atmosphere and mitigates submarine instability issues. The geomechanical and hydraulic properties of hydrate-bearing sediments play a crucial role in understanding the reservoir responses during methane gas production from natural hydrate deposits.
This thesis delves into the laboratory characterization of natural sediments using tetrahydrofuran hydrate as an analog for methane hydrate. The work begins with analyzing pressure core permeability data to develop a unified permeability model for hydrate-bearing sediments. The experimental study customizes unique testing devices to measure the compressibility, soil-water characteristic curve, permeability anisotropy, and wave velocity for various samples recovered from the hydrate reservoirs in the Gulf of America and Alaska North Slope. Laboratory characterization of natural sediments containing tetrahydrofuran hydrate allows parametric investigations of how hydrate saturation affects these fundamental geomechanical and hydraulic properties. A comparative study of pressure core testing of methane hydrate-bearing sediments and laboratory testing of tetrahydrofuran hydrate-bearing sediments is also conducted to reveal the impacts of different testing methods on measured properties. This research provides insight into the characteristics of hydrate-bearing sediments and impacts of testing methods on the fidelity of measured data.