The Loncopué Trough: A Cenozoic basin produced by extension in the southern Central Andes     

Andrés Folguera  Emilio Rojas Vera  Germán Bottesi  Gonzalo Zamora Valcarce  Victor A. Ramos 《Journal of Geodynamics》2010,49(5):287-295

The Loncopué Trough is located in the hinterland Andean zone between 36°30′ and 39°S. It constitutes a topographic low bounded by normal faults and filled by lavas and sediments less than 5 Ma old. Reprocessed seismic lines show wedge-like depocenters up to 1700 m deep associated with high-angle faults, correlated with the 27–17 Ma Cura Mallín basin deposits, and buried beneath Pliocene to Quaternary successions and Late Miocene foreland sequences. The southern Central Andes seem to have been under extension in the hinterland zone some 27 Ma ago and again at approximately 5 Ma ago. This last extensional period could have been the product of slab steepening after a shallow subduction cycle in the area, although other alternatives are discussed. Orogenic wedge topography, altered by the first extensional stage in the area, was recovered through Late Miocene inversion, and was associated with foreland sequences. However, since the last extension (<5 Ma) the Andes have not recovered their characteristic contractional behavior that controlled past orogenic growth.  相似文献   

First find of PGE minerals in sulfide ores related to ultrabasic rocks of the IIsk-Kuksher trough,southern Siberia     

A. S. Mekhonoshin  T. B. Kolotilina  L. A. Pavlova 《Doklady Earth Sciences》2008,419(2):435-437

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Brain acetylcholinesterase as a marine pesticide biomarker using Brazilian fishes     

Oliveira MM  Silva Filho MV  Cunha Bastos VL  Fernandes FC  Cunha Bastos J 《Marine environmental research》2007,63(4):303-312

Brain acetylcholinesterase (AChE) of some fishes from the coast of Rio de Janeiro State was studied as a possible pesticide biomarker in marine environmental monitoring. AChE specific activity in brain varied from 145 to 530 U/g of proteins and the Michaelis-Menten constant (K(M)) for acetylthiocholine varied from 104 to 291 microM among the 20 species studied. The enzyme sensitivity to methyl paraoxon, evaluated by the inhibition kinetic constants, shows that some species (Paralonchurus brasiliensis and Genidens genidens) are more sensitive (IC50-30 min=455 and 468 nM, respectively). The less sensitive Merluccius hubbsi and Percophis brasiliensis (IC50-30 min=3339 and 3259 nM, respectively) belong to the super-order Paracanthopterygii, which includes the more ancient species. On the other hand, more susceptible species belong to the super-order Acanthopterygii, which includes more recent species. These results suggest a possible evolutionary linkage for AChE sensitivity to methyl paraoxon. The application of inhibition kinetic constants for fish brain AChE in phylogenetic studies is still being investigated. The results have shown that a fish sentinel species should have the highest brain AChE level among the more sensitive ones.  相似文献   

The influence of geochemical processes in the near-bottom layer on the hydrochemical characteristics of the waters of the Sea of Japan     

P. Ya. Tishchenko  L. D. Talley  V. B. Lobanov  A. P. Nedashkovskii  G. Yu. Pavlova  S. G. Sagalaev 《Oceanology》2007,47(3):350-359

According to the results of the international expedition aboard the R/Vs Roger Revelle and Professor Khromov in the summer 1999, areas with low oxygen contents (below 210 μM/kg) and those with increased contents of dissolved inorganic carbon and phosphates were found that roughly coincided with one another. These areas are located near the bottom on the southwestern slope of the Tsushima Basin in the region of the Korea Strait and on the continental slope in the region of the Tatar Strait in the northern part of the sea at about 46° N. The set of hydrochemical data points to a high geochemical activity in the near-bottom layer of the areas noted. This activity is confirmed by direct observations of the composition of the interstitial water in the sediments collected in the northern part of the sea during the expedition of R/V Akademik M.A. Lavrent’ev in 2003. It was supposed that the main cause of the increased geochemical activity is the runoff of suspended and dissolved matter from the Korea and Tatar straits. In the areas mentioned, the near-bottom waters are characterized by low values of the nitrogen-phosphorus ratio (below 10), which is geochemical proof of the denitrification process occurring under the conditions of high oxygen concentrations characteristic of the Sea of Japan. Based on the value of the annual production in the Sea of Japan, a rate of denitrification equal to 3.4 × 10¹² gN/year was calculated. Hence, it is confirmed that the geochemical processes in the near-bottom layer have a direct influence on the spatiotemporal characteristics of the hydrochemical properties of the waters of the Sea of Japan.  相似文献   

Climate of Russia in the 21st century. Part 1. New evidence of anthropogenic climate change and the state of the art of its simulation     

V. P. Meleshko  V. M. Kattsov  V. M. Mirvis  V. A. Govorkova  T. V. Pavlova 《Russian Meteorology and Hydrology》2008,33(6):341-350

This is the first of three papers devoted to the study of climate change in Russia in the 20th and 21st centuries using ensembles of CMIP3 Atmosphere-Ocean General Circulation Models. Current studies of observed global and regional climate changes are briefly reviewed based on the analysis of the Intergovernmental Panel on Climate Change (IPCC). The anthropogenic nature of climate change is emphasized. It is also noted that the observed warming in Russia is significantly larger than global warming. Alternative hypotheses on causes of global climate changes discussed in some Russian publications are reviewed and their groundlessness is shown. The paper discusses some characteristics of ensembles of CMIP3 models that participated in the preparation of the IPCC Fourth Assessment Report. A model quality index is introduced. The dependence of simulated climate change in Russia on the choice of model ensembles and emission scenarios is considered. It is shown that the climate change in Russia does not depend significantly on the emission scenario choice until the middle of the 21st century.  相似文献   

Modes of Ag occurrence in the loose deposits of dispersal trains at Au-Ag mineral deposits     

R. G. Kravtsova  L. A. Pavlova  Yu. I. Rogozina 《Geochemistry International》2010,48(7):731-736

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First data on forms of gold occurrence in lithochemical sedimental streams of the Gold-Silver Dukat deposit (Northeastern Russia)     

R. G. Kravtsova  L. A. Pavlova  Yu. I. Rogozina  A. S. Makshakov 《Doklady Earth Sciences》2010,434(1):1184-1191

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Stanniferrous granites of Vietnam: Rb-Sr and Ar-Ar isotope age,composition, sources,and geodynamic formation conditions     

Anh  Phan Luu  Vladimirov  A. G.  Kruk  N. N.  Polyakov  G. V.  Ponomarchuk  V. A.  Hoa  Tran Trong  Phuong  Ngo Thi  Kuibida  M. L.  Annikova  I. Yu.  Pavlova  G. G.  Kiseleva  V. Yu. 《Doklady Earth Sciences》2010,432(2):839-845

Doklady Earth Sciences - Stanniferrous granite-leucogranite massifs in Vietnam to which the bedrock and placer commercial deposits of cassiterite are associated (Timtuc etc.) are of late Cretaceous...  相似文献   

John Aitchison: Krumbein Medalist     

Vera Pawlowsky Glahn 《Mathematical Geology》1999,31(1):139-142

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Origin of REE-rich ferrocarbonatites in southern Siberia (Russia): implications based on melt and fluid inclusions     

Ilya R. Prokopyev  Alexander S. Borisenko  Andrey A. Borovikov  Galina G. Pavlova 《Mineralogy and Petrology》2016,110(6):845-859

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