Krista Davies
Krista Davies is currently undertaking her PhD research in Hydrogen Subsurface Geochemistry at the School of Engineering, Centre for Energy and Sustainable Resources at Edith Cowan University. She holds a Masters Degree in Environmental Science specializing in Inland Aquatic and Marine Systems and a Bachelor of Applied Science in Geology with First Class Honours. With over 28 years of experience in oil and gas exploration, Krista has dedicated the past three years exclusively to natural hydrogen exploration, aligning with her passion for addressing global resource and environmental challenges through practical and sustainable approaches. As the Principal Geoscientist at Cryptid Energy Consultants, Krista remains at the forefront of geological and geophysical consulting for the energy industry. Her extensive career includes notable contributions at Gehyra Flux, Ophir Energy, Shell Development Australia, and Woodside Energy, specializing in sequence stratigraphy, seismic interpretation, and prospect generation both onshore and offshore. Krista has worked with various companies, from small caps to multinational corporations, throughout South East Asia.
This study investigates natural hydrogen seepage in the Yilgarn Craton of Western Australia, focusing on the FF4 site where long-term autonomous monitoring was conducted. The Wongan Hills area, characterized by Archean metamorphosed basalts, gabbros, chlorite schists, serpentinites, and banded iron formations, adjacent to vast Archean granitoid terrains, provides an ideal geological setting for studying natural hydrogen emissions. Data were collected across three distinct seasons to understand the relationship between hydrogen concentrations and groundwater levels. The results show significant seasonal fluctuations in hydrogen emissions, with high concentrations recorded after dry summers and reduced levels following rainfall due to increased groundwater presence. The monitoring revealed that hydrogen seepage is significantly influenced by seasonal groundwater levels. During dry periods, hydrogen concentrations reached peaks of >500 ppm, while post-rainfall periods saw a decline in hydrogen emissions, attributed to increased groundwater acting as a barrier to seepage. This correlation suggests that groundwater saturation may inhibit hydrogen escape through the near subsurface, leading to potential false negatives in soil gas surveys conducted after rainfall. Additionally, the study observed the effects of barometric pressure pumping on hydrogen soil gas fluctuations. Variations in atmospheric pressure were found to impact the diffusion of hydrogen gas to the surface, with pressure drops enhancing seepage rates and pressure increases reducing them. This phenomenon further complicates the detection and monitoring of hydrogen emissions, necessitating consideration of barometric pressure trends alongside hydrological conditions. These findings highlight the need for careful timing of soil gas sampling for hydrogen exploration to account for seasonal environmental conditions. The data highlight the importance of repeat monitoring in the accurate detection of natural hydrogen seeps and contribute to the broader understanding of subsurface hydrogen dynamics, essential for advancing natural hydrogen exploration and exploitation.
Co-author: Emanuelle Frery, Lionel Esteban, Alireza Keshavarz, Stefan Iglauer
EDITH COWAN UNIVERSITY
Phd Candidate
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