Numerous hydrocarbon seep sites at the continental shelf, slope, and in deep water basin are known to feed Black Sea reservoir of dissolved methane. In this study, we identified likely sources gas oil that emitted four located on slope offshore Georgia Eastern 830 1,140 m depth – an area with seepage only (Batumi area) three areas coupled (Iberia Mound, Colkheti Seep, Pechori Mound). The geoche...

Carbon isotope fractionation factors associated with the aerobic consumption of methane (C1), ethane (C2), propane (C3), and nbutane (C4) were determined from incubations of marine sediment collected from the Coal Oil Point hydrocarbon seep field, located offshore Santa Barbara, CA. Hydrogen isotope fractionation factors for C1, C2 and C3 were determined concurrently. Fresh sediment samples fro...

To extract all the oil from a well, petroleum engineers pump hot reactive chemicals into the well. These Enhanced Oil Recovery (EOR) processes need to be thoroughly monitored, since the injected fluids can seep out of the production oil wells and, if unchecked, eventually pollute sources of drinking water. There is a need to measure the corresponding effects. One way to measure these undergroun...

The Coal Oil Point (COP) seeps offshore Goleta, CA, are estimated to release 20-25 tons of oil daily, providing an ideal natural laboratory to investigate the fate of oil in the coastal ocean. To address the long-term fate of COP oil, we collected 15 sediment samples down current from the seeps and quantified petroleum content and individual biomarkers using traditional and comprehensive two-di...

Bacterial community structures were evaluated in oil samples using culture-independent pyrosequencing, including oil mousses collected on sea surface and salt marshes during the Deepwater Horizon oil spill, and oil deposited in sediments adjacent to the wellhead 1 year after the spill. Phylogenetic analysis suggested that Erythrobacter, Rhodovulum, Stappia, and Thalassospira of Alphaproteobacte...

When wind speeds are 2-10 m s-1, reflective contrasts in the ocean surface make oil slicks visible to synthetic aperture radar (SAR) under all sky conditions. Neural network analysis of satellite SAR images quantified the magnitude and distribution of surface oil in the Gulf of Mexico from persistent, natural seeps and from the Deepwater Horizon (DWH) discharge. This analysis identified 914 nat...

Two quantitative retrieval techniques were evaluated to estimate methane (CH4) enhancement in concentrated plumes using high spatial and moderate spectral resolution data from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). An iterative maximum a posteriori differential optical absorption spectroscopy (IMAP-DOAS) algorithm performed well for an ocean scene containing natural CH4 em...

Methane cold seep systems typically exhibit extensive buildups of authigenic carbonate minerals, resulting from local increases in alkalinity driven by methane oxidation. Here, we demonstrate that modern seep authigenic carbonates exhibit anomalously low clumped isotope values (Δ47), as much as ∼0.2‰ lower than expected values. In modern seeps, this range of disequilibrium translates into appar...

The importance of tectonics and fluid flow in controlling cold seep habitats has long been appreciated at convergent margins but remains poorly understood in strike-slip systems. Here we present geophysical, geochemical, and biological data from an activemethane seep offshore fromDelMar, California, in the inner California borderlands (ICB). The location of this seep appears controlled by local...