Geology topics

C.D. Ruppel

Publications and source records attributed to C.D. Ruppel.

3 recordsLinked to original sources

USGS2013

Evidence for extensive methane venting on the southeastern U.S. Atlantic margin

We present the first evidence for widespread seabed methane venting along the southeastern United States Atlantic margin beyond the well-known Blake Ridge diapir seep. Recent ship- and autonomous underwater vehicle (AUV)–collected data resolve multiple water-column anomalies (>1000 m height) and extensive new chemosynthetic seep communities at the Blake Ridge and Cape Fear diapirs. These results indicate that multiple, highly localized fluid conduits punctuate the areally extensive Blake Ridge gas hydrate province, and enable the delivery of significant amounts of methane to the water column. Thus, there appears to be an abundance of seabed fluid flux not previously ascribed to the Atlantic margin of the United States.

Geology↗

USGS2006

Comment on "Thermal and visual time-series at a seafloor gas hydrate deposit on the Gulf of Mexico slope," by I.R. MacDonald, L.C. Bender, M. Vardaro, B. Bernard, and J.M. Brooks[Earth Planet. Sci. Lett. 233 (2005) 49-59]

[No abstract available]

Earth and Planetary Science Letters↗

USGS2002

Thermal conductivity measurements in porous mixtures of methane hydrate and quartz sand

Using von Herzen and Maxwell's needle probe method, we measured thermal conductivity in four porous mixtures of quartz sand and methane gas hydrate, with hydrate composing 0, 33, 67 and 100% of the solid volume. Thermal conductivities were measured at a constant methane pore pressure of 24.8 MPa between -20 and +15??C, and at a constant temperature of -10??C between 3.5 and 27.6 MPa methane pore pressure. Thermal conductivity decreased with increasing temperature and increased with increasing methane pore pressure. Both dependencies weakened with increasing hydrate content. Despite the high thermal conductivity of quartz relative to methane hydrate, the largest thermal conductivity was measured in the mixture containing 33% hydrate rather than in hydrate-free sand. This suggests gas hydrate enhanced grain-to-grain heat transfer, perhaps due to intergranular contact growth during hydrate synthesis. These results for gas-filled porous mixtures can help constrain thermal conductivity estimates in porous, gas hydrate-bearing systems.

Geophysical Research Letters↗