Characteristics and varieties of gases enclathrated in natural gas hydrates retrieved at Lake Baikal.

Molecular and stable isotope compositions of hydrate-bound gases collected from 59 hydrate-bearing sites between 2005 to 2019 in the southern and central sub-basins of Lake Baikal are reported. The δH of the hydrate-bound methane is distributed between - 310‰ and - 270‰, approximately 120‰ lower than its value in the marine environment, due to the difference in δH between the lake water and seawater. Hydrate-bound gases originate from microbial (primary and secondary), thermogenic, and mixed gas sources.

What controls the remobilization and deformation of surficial sediment by seismic shaking? Linking lacustrine slope stratigraphy to great earthquakes in South-Central Chile.

Remobilization and deformation of surficial subaqueous slope sediments create turbidites and soft sediment deformation structures, which are common features in many depositional records. Palaeoseismic studies have used seismically-induced turbidites and soft sediment deformation structures preserved in sedimentary sequences to reconstruct recurrence patterns and - in some cases - allow quantifying rupture location and magnitude of past earthquakes. However, current understanding of earthquake-triggered remobilization and deformation lacks studies targeting where these processes take place, the subaqueous slope and involving direct comparison of sedimentary fingerprint with well-documented historical earthquakes.

Characteristics of hydrate-bound gas retrieved at the Kedr mud volcano (southern Lake Baikal).

We reported the characteristics of hydrate-bound hydrocarbons in lake-bottom sediments at the Kedr mud volcano in Lake Baikal. Twenty hydrate-bearing sediment cores were retrieved, and methane-stable isotopes of hydrate-bound gases (δC and δH of - 47.8‰ to - 44.

Two-stage opening of the Dover Strait and the origin of island Britain.

Late Quaternary separation of Britain from mainland Europe is considered to be a consequence of spillover of a large proglacial lake in the Southern North Sea basin. Lake spillover is inferred to have caused breaching of a rock ridge at the Dover Strait, although this hypothesis remains untested. Here we show that opening of the Strait involved at least two major episodes of erosion.

Spatial distribution of methane over Lake Baikal surface.

The results of application of a high sensitivity methane laser detector to investigations of the methane concentration in the atmosphere over Baikal lake are presented as well as methane flows from the water into the atmosphere. The measurements were conducted at a stationary station and aboard the research vessel "Vereschagin" during two summer expeditions in 2003 and 2004. Mean background concentration was equal to (2.