971 resultados para landfill gas emission measurements


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We report analyses of porosity and permeability of core samples from Site 1193 in the Northern Marion Platform, Sites 1196 and 1199 in the Southern Marion Platform, and Sites 1194, 1195, 1197, and 1198 from the slopes of these platforms. The samples include 415 horizontal 1-in plugs, 290 vertical 1-in plugs, and 23 whole-core pieces. Porosity and permeability analyses were possible for most, but not all, samples. Grain density measurements were also obtained for the horizontal plugs. Representative photomicrographs are provided of thin sections from 139 of the horizontal plugs and the 23 whole-core pieces.

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Ocean Drilling Program (ODP) Leg 164 recovered a number of large solid gas hydrate from Sites 994, 996, and 997 on the Blake Ridge. Sites 994 and 997 samples, either nodular or thick massive pieces, were subjected to laboratory analysis and measurements to determine the structure, molecular and isotopic composition, thermal conductivity, and equilibrium dissociation conditions. X-ray computed tomography (CT) imagery, X-ray diffraction, nuclear magnetic resonance (NMR), and Raman spectroscopy have revealed that the gas hydrates recovered from the Blake Ridge are nearly 100% methane gas hydrate of Structure I, cubic with a lattice constant of a = 11.95 ± 0.05 angström, and a molar ratio of water to gas (hydration number) of 6.2. The d18O of water is 2.67 per mil to 3.51 per mil SMOW, which is 3.5-4.0 heavier than the ambient interstitial waters. The d13C and dD of methane are -66 per mil to -70 per mil and -201 per mil to -206 per mil, respectively, suggesting that the methane was generated through bacterial CO2 reduction. Thermal conductivity values of the Blake Ridge hydrates range from 0.3 to 0.5 W/(m K). Equilibrium dissociation experiments indicate that the three-phase equilibrium for the specimen is 3.27 MPa at 274.7 K. This is almost identical to that of synthetic pure methane hydrate in freshwater.