PGE distribution in deformed lherzolites of the Udachnaya kimberlite pipe (Yakutia)

The results of the first study of the PGE distribution in deformed lherzolites of the Udachnaya kimberlite pipe (Yakutia) are presented here. The complex character of evolution of the PGE composition in the Deformed lherzolites is assumed to be the result of silicate metasomatism. At the first stage, growth in the amount of clinopyroxene and garnet in the rock is accompanied by a decrease in the concentration of the compatible PGE (Os, Ir). During the final stage, the rock is enriched with incompatible PGE (Pt, Pd) and Re possible due to precipitation of submicron-sized particles of sulfides in the interstitial space of these mantle rocks.     

Strength analysis of the frozen-ground enclosure of a low-temperature storage reservoir for liquefied gases

The geometrical dimensions of a frozen-ground enclosure for a low-temperature storage reservoir are determined from a static designstorage reservoir are determined from a static design on the assumption of a safe excavation of ground in digging the trench. Neglecting the combined work of the enclosure and surrounding thawing rock mass, the problem is reduced to the design of the frozen-ground shell, stressed along its outer contour by the thawing ground pressure.

To estimate the tension of the wall of an enclosure it is sufficient to use the solution of the problem of a thick-walled tube subjected to ambient pressure. It is difficult to find a sufficiently simple analogue for the problem of the bottom. The solution of the plate-bending problem locates the neutral line in the middle of the section when there are equal tensile and compressive stresses at the inner and the outer contour. If the combined work of the bottom of the section and the wall is taken into account, the neutral line shifts from the centre of the bottom to the inner contour of the enclosure, i.e., the compressive stresses exceed the tensile ones, which is of particular importance for materials with different resistance to compression and tension.     

NATURAL ENVIRONMENT AND RESOURCES OF THE WORLD—A NEW SOVIET ATLAS

The authors employ remote sensing imagery and existing landscape maps to gain greater insight into how pre-glacial tectonic activity contributes to landscape development in old glaciated regions by affecting the form and movements of lobes of past continental ice sheets. Using the Belorussian SSR as a study area, the authors identify several features of current landscape structure which can serve as indicators of past tectonic activity, the most reliable being various characteristics of the landscape family—defined as a combination of natural territorial complexes of similar origin and age. Translated from: Izvestiya Vsesoyuznogo Geograficheskogo Obshchestva, 1990, No. 6, pp. 560–565.     

Forest carbon stocks and fluxes in physiographic zones of India

Background  

Reducing carbon Emissions from Deforestation and Degradation (REDD+) is of central importance to combat climate change. Foremost among the challenges is quantifying nation's carbon emissions from deforestation and degradation, which requires information on forest carbon storage. Here we estimated carbon storage in India's forest biomass for the years 2003, 2005 and 2007 and the net flux caused by deforestation and degradation, between two assessment periods i.e., Assessment Period first (ASP I), 2003-2005 and Assessment Period second (ASP II), 2005-2007.     

Lenticular galaxies with ultraviolet rings

Based on GALEX (Galaxy Ultraviolet Explorer) data, we have compiled a list of lenticular galaxies with ultraviolet rings—radially localized star-forming regions. We have analyzed the optical structure of these galaxies using SDSS (Sloan Digital Sky Survey) surface photometry, measured the colors of the rings, and compared the radial localizations of the ring structures in the optical and ultraviolet spectral ranges. Possible scenarios for the formation of ring star-forming regions in lenticular galaxies having no other structural peculiarities and exhibiting a homogeneous old stellar population outside the rings are discussed.     

Interaction of the Extended Envelope of a Hot Jupiter with a Narrow Coronal Mass Ejection

The passage of a hot Jupiter with a quasi-closed extended envelope through a short coronal mass ejection (CME) with a small opening angle is considered. The results of three-dimensional gasdynamical simulations are used to determine the characteristics of the flow in the planet’s envelope as it intersects the CME, and to infer possible observational manifestations of such an event. Two options are considered—entry of the planet into the CME at the beginning of the CME and a tangential interaction with the leading edge of the CME. The mass lost by the planet as a result of its interaction with the CME is estimated.

     

Historical demography of southern African patellid limpets: congruence of population expansions,but not phylogeography

Global climatic oscillations have shaped the contemporary genetic structure of marine taxa in different ways. Previous demographic studies have indicated that various intertidal marine species display genetic signatures of demographic expansion that either pre- or postdate the Last Glacial Maximum. Such expansions and the ability of species to colonise new habitats will influence their genetic structure, but the link between scales of larval dispersal and the strength of phylogeographic structure is not always clear. We analysed a fragment of the mitochondrial COI gene of 11 sympatric species of intertidal southern African patellid limpets to investigate how ancient oceanographic dynamics have shaped and maintained their contemporary spatial genetic variation. Our data show that the patellid limpets investigated display congruent evidence of spatial expansion during the Late Pleistocene or Early Holocene, which corresponds with the establishment of the contemporary southern African shoreline. We argue that closely related and co-distributed southern African intertidal invertebrates responded to ancient climatic oscillations as a cohesive group. In contrast, contemporary oceanographic circulation has shaped the phylogeographic patterns of these limpets in different ways. We show close relationships between phylogeography and biogeography for some species, but not for others, despite the similarities in their life histories and exposure to the same climatic changes.     

INSTABILITY OF DECOMPOSED GRANITE CUT SLOPES CAUSED BY EXPANSIVE CLAY LAYERS

The ever increasing need of smoother flow of traffic in Japan is being met by constructing newer and wider wads as well as developing best possible road network. Many such roads need to pass across the hills and mountains that make nearly 75% of the country's land. When a tunnel is not feasible or possible, the option goes to cutting slopes to acquire the necessary space for the highways. Cutting natural slopes, however, results in a risk of slope failure. The instability of a cut slope might be caused by various factors but one prominent reason is stress release, which disturbs the balance of stresses along the potential lime of failure. This paper introduces some cases of cut slope failures in decomposed granite zones under the influence of clay veins, and discusses the causes of failures from mineralogical and geotechnical points of views. As a result of the laboratory tests, it was revealed that the clay veins consist of expansive clay minerals such as smectite, which up on stress release absorb more water and weaken the clay veins. This process then results in failure of the cut slopes along the veins.