Paleoearthquakes in the Uimon basin (Gorny Altai)

Paleoseismological studies confirm that the Uimon basin is thrust by its northern mountain border along the active South Terekta fault. The latest motion along the fault in the 7-8th centuries AD induced an earthquake with a magnitude of M_w= 7.4-7.7 and a shaking intensity of I = 9-11 on the MSK-64 scale. The same fault generated another event (M > 7, I = 9-10), possibly, about 16 kyr ago, which triggered gravity sliding. The rockslide dammed the Uimon valley and produced a lake, where lacustrine deposition began about 14 ± 1 kyr ago, and a later M > 7 (I = 9-10) earthquake at ~ 6 ka caused the dam collapse and the lake drainage. Traces of much older earthquakes that occurred within the Uimon basin are detectable from secondary deformation structures (seismites) in soft sediments deposited during the drainage of a Late Pleistocene ice-dammed lake between 100 and 90 ka and in ~ 77 ka alluvium. The magnitude and intensity of these paleoearthquakes were at least M > 5.0-5.5 and I > 6-7.     

Seasonal Dynamics of Microbial Processes in Bottom Sediments of the Sevastopol Coastal Area

Oceanology - A seasonal study of microbial methane oxidation (MO) and sulfate reduction (SR) processes in bottom sediments was carried out at five stations in the estuarian Sevastopol coastal area,...     

Biogeochemical processes in the Chukchi Sea

Study of biogeochemical processes in water and sediments of the Chukchi Sea in August 2004 revealed atypical maximums of the concentration of biogenic elements (N, P, and Si) and the rate of microbial sulfate reduction in the surface layer (0–3 cm) of marine sediments. The C: N: P ratio in the organic matter (OM) of this layer does not fit the Redfield-Richards stoichiometric model. Specific features of biogeochemical processes in sea are likely related to the complex dynamics of water, high primary productivity (110–1400 mg C/(m² day)), low depth of basin (<50 m in 60% of the water area), reduced food chain due to low population of zooplankton, high density of zoobenthos (up to 4230 g m^?2), and high activity of microbial processes. Drastic decrease in the concentration of biogenic elements, iodine, total alkalinity (Alk), and population of microorganisms beneath the 0–3 cm layer testify to a large-scale OM decay at the water-seafloor barrier. Our original experimental data support the high annual rate of OM mineralization at the bottom of the Chukchi Sea.     

Microbial processes of carbon cycle as the base of food chain of Håkon Mosby Mud Volcano benthic community

Box and gravity cores recovered from the Håkon Mosby mud volcano (HMMV) during cruise 15 of the R/V Professor Logachev were analyzed for bacterial activity and benthic fauna distribution. The high bacterium number (up to 9.6×10⁹ cells cm^-3 of the sediment) and marked rates of sulfate reduction (up to 0.155?mg?S?dm^-3?day^-1) and methane oxidation (up to 9.9?μg?C?dm^-3?day^-1) were shown for the upper horizons of the sediments of the HMMV peripheral zone. The benthic community is characterized by the presence of two pogonophoran species, Oligobrachia sp. and Sclerolinum sp., harboring symbiotic methanotrophic bacteria.     

Landslide Research at the British Geological Survey:Capture,Storage and Interpretation on a National and Site-Specific Scale

Abstract: Landslide research at the British Geological Survey (BGS) is carried out through a number of activities, including surveying, database development and real-time monitoring of landslides. Landslide mapping across the UK has been carried out since BGS started geological mapping in 1835. Today, BGS geologists use a combination of remote sensing and ground-based investigations to survey landslides. The development of waterproof tablet computers (BGS·SIGMAmobile), with inbuilt GPS and GIS for field data capture provides an accurate and rapid mapping methodology for field surveys. Regional and national mapping of landslides is carried out in conjunction with site-specific monitoring, using terrestrial LiDAR and differential GPS technologies, which BGS has successfully developed for this application. In addition to surface monitoring, BGS is currently developing geophysical ground-imaging systems for landslide monitoring, which provide real-time information on subsurface changes prior to failure events. BGS’s mapping and monitoring activities directly feed into the BGS National Landslide Database, the most extensive source of information on landslides in Great Britain. It currently holds over 14?000 records of landslide events. By combining BGS’s corporate datasets with expert knowledge, BGS has developed a landslide hazard assessment tool, GeoSure, which provides information on the relative landslide hazard susceptibility at national scale.     

Quaternary travertine of the Kurai fault zone (Gorny Altai)

In the Kurai fault zone, travertine forms a matrix cementing clastic material of colluvial and glacial deposits or rarely forming a stockwork in a system of fractures in Palaeozoic rocks. The regular change of composition of solutions in the process of travertine formation has resulted in change of stable Mg–calcite by Sr–aragonite. According to the carbon isotopic composition, the travertine has intermediate genesis between thermal and meteogene. The light oxygen isotopic composition of CaCO₃ indicates formational water input. The carbonates inherited Y, Sr, U, and Ni and in some areas, V, As, and Zn from the endogeneous water sources. Given that the Kurai zone travertine cements the Late Pleistocene–Holocene sediments and ¹⁴C dating of the carbonates gives a range of >40 000–3475 ± 35 years, the faults serving as routes of migration of the solutions forming the travertine should be considered as active structures.     

Biogeochemical processes in the water column of the Caspian Sea in November 2008

Doklady Earth Sciences -     

Hydrochemical and Microbiological Features of Lake Mogil'noe

A comprehensive hydrochemical and microbiological study was conducted in Lake Mogil'noe. The vertical hysrochemical structure of the lake was analyzed. Large amounts of mineral compounds containing biogenic elements and their organic forms are shown to accumulate in the anaerobic zone of the lake. An abrupt increase in the concentration of C_org is recorded in the near-bottom layer, where it is almost an order of magnitude higher than that in the anaerobic zone of the Black Sea at a depth of 2000 m. All the processes are found to be most rapid in the boundary layer between the aerobic and anaerobic zones (8.25–9.25 m), where the primary production attains its maximum, the concentration of sulfates abruptly increases relative to the aerobic and anaerobic zones, microorganism population is maximum, as are the rates of sulfate reduction and glucose consumption by heterotrophic organisms.     

Seasonal Dynamics of Biogeochemical Processes in the Water Column of the Northeastern Black Sea

Integrated studies on the hydrochemistry and water column rates of microbial processes in the eastern sector of the Black Sea along a standard 100-miles transect off Gelendzhik from the coast to the central part of the sea at water depths of 100–2170 m show that a series of warm winters and the absence of intense convective winter mixing resulted in a relatively low content of suspended particulate matter (SPM), particulate organic carbon (POC), and nutrients in the water column in March 2009. The relatively high SPM concentrations and the presence of isotopically light POC at the offshore station are indicative of the supply of terrigenous material from land and low contributions of phytoplanktonic organic matter to the composition of SPM. This may explain the low rates of biogeochemical processes in the water column near the coast. The surface layer at deep-water stations is dominated by isotopically heavy phytoplanktonic organic matter. This suggests that the supply of terrigenous material from land was insufficient in offshore deep-water areas. Therefore, warm winters and insufficient nutrient supply do not prevent photosynthesis in the photic layer of the deep-water zone, which generates organic substrates for heterotrophic aquatic communities. The results of isotopic analysis of POC, measurements of the rates biogeochemical processes, and the hydrochemical characteristics of the water column can be used to determine the nature and seasonal variability of the POC composition.