Steve Phillips is fascinated by gas hydrate systems and early diagenesis in marine sediments. He aims to better understand these systems by integrating sedimentology, geochemistry, and physical property measurements as part of multidisciplinary scientific drilling expeditions. He has worked in the Gulf of Mexico, Bay of Bengal, Cascadia Margin, and offshore Japan.
Professional Experience
2020 – present Research Geologist, U.S. Geological Survey
2019 – 2020 Research Associate, University of Texas at Austin – Institute for Geophysics
2015 – 2019 Postdoctoral Fellow, University of Texas at Austin – Institute for Geophysics
Education and Certifications
2015 PhD Oceanography, University of New Hampshire
2007 MS Earth Sciences: Geochemical Systems, University of New Hampshire
2004 BS Geology, Michigan Technologic
Science and Products
Compression behavior of hydrate-bearing sediments
Permeability of methane hydrate-bearing sandy silts in the deep-water Gulf of Mexico (Green Canyon Block 955)
Integrated geochemical approach to determine the source of methane in gas hydrate from Green Canyon Block 955 in the Gulf of Mexico
Comparison of sediment composition by smear slides to quantitative shipboard data: A case study on the utility of smear slide percent estimates, IODP Expedition 353, northern Indian Ocean
Thermodynamic insights into the production of methane hydrate reservoirs from depressurization of pressure cores
Primary deposition and early diagenetic effects on the high saturation accumulation of gas hydrate in a silt dominated reservoir in the Gulf of Mexico
Isolating detrital and diagenetic signals in magnetic susceptibility records from methane-bearing marine sediments
U.S. Geological Survey Gas Hydrates Project
Science and Products
- Publications
Compression behavior of hydrate-bearing sediments
This work experimentally explores porosity, compressibility, and the ratio of horizontal to vertical effective stress (K0) in hydrate-bearing sandy silts from Green Canyon Block 955 in the deep-water Gulf of Mexico. The samples have an in situ porosity of 0.38 to 0.40 and a hydrate saturation of more than 80%. The hydrate-bearing sediments are stiffer than the equivalent hydrate-free sediments; thAuthorsYi Fang, Peter Flemings, John Germaine, Hugh Daigle, Stephen C. Phillips, Joshua O'ConnellPermeability of methane hydrate-bearing sandy silts in the deep-water Gulf of Mexico (Green Canyon Block 955)
Permeability is one of the most crucial properties governing fluid flow in methane hydrate reservoirs. This paper presents a comprehensive permeability analysis of hydrate-bearing sandy silt pressure-cored from Green Canyon Block 955 (GC 955) in the deep-water Gulf of Mexico. We developed an experimental protocol to systematically characterize the transport and petrophysical properties in pressureAuthorsYi Fang, Peter Flemings, Hugh Daigle, Stephen C. Phillips, Joshua O'ConnellIntegrated geochemical approach to determine the source of methane in gas hydrate from Green Canyon Block 955 in the Gulf of Mexico
Massive volumes of gas are sequestered within gas hydrate in subsurface marine sediments in the Gulf of Mexico. Methane associated with gas hydrate is a potentially important economic resource and a significant reservoir of carbon within the global carbon cycle. Nevertheless, uncertainties remain about the genetic source (e.g., microbial, thermogenic) and possible migration history of natural gasAuthorsMyles T. Moore, Stephen C. Phillips, Ann Cook, Thomas H. DarrahComparison of sediment composition by smear slides to quantitative shipboard data: A case study on the utility of smear slide percent estimates, IODP Expedition 353, northern Indian Ocean
Smear slide petrography has been a standard technique during scientific ocean drilling expeditions to characterize sediment composition and classify sediment types, but presentation of these percent estimates to track downcore trends in sediment composition has become less frequent over the past 2 decades. We compare semi-quantitative smear slide composition estimates to physical property (naturalAuthorsStephen C. Phillips, Kate LittlerThermodynamic insights into the production of methane hydrate reservoirs from depressurization of pressure cores
We present results of slow (multiple day) depressurization experiments of pressure cores recovered from Green Canyon Block 955 in the northern Gulf of Mexico during The University of Texas at Austin Hydrate Pressure Coring Expedition (UT-GOM2-1). These stepwise depressurization experiments monitored the pressure and temperature within the core storage chamber during each pressure step, or “shut-inAuthorsStephen C. Phillips, Peter B. Flemings, Kehua You, William F. WaitePrimary deposition and early diagenetic effects on the high saturation accumulation of gas hydrate in a silt dominated reservoir in the Gulf of Mexico
On continental margins, high saturation gas hydrate systems (>60% pore volume) are common in canyon and channel environments within the gas hydrate stability zone, where reservoirs are dominated by coarse-grained, high porosity sand deposits. Recent studies, including the results presented here, suggest that rapidly deposited, silt-dominated channel-levee environments can also host high saturationAuthorsJoel E. Johnson, Douglas R. MacLeod, Stephen C. Phillips, Marcie Phillips Purkey, David L. DivinsIsolating detrital and diagenetic signals in magnetic susceptibility records from methane-bearing marine sediments
Volume-dependent magnetic susceptibility (κ) is commonly used for paleoenvironmental reconstructions in both terrestrial and marine sedimentary environments where it reflects a mixed signal between primary deposition and secondary diagenesis. In the marine environment, κ is strongly influenced by the abundance of ferrimagnetic minerals regulated by sediment transport processes. Post-depositional aAuthorsJoel P. L. Johnson, Stephen C. Phillips, William Clyde, Liviu Giosan, Marta E. Torres - Science
U.S. Geological Survey Gas Hydrates Project
The USGS Gas Hydrates Project has been making contributions to advance understanding of US and international gas hydrates science for at least three decades. The research group working on gas hydrates at the USGS is among the largest in the US and has expertise in all the major geoscience disciplines, as well as in the physics and chemistry of gas hydrates, the geotechnical properties of hydrate... - Multimedia