Using numerical modelling to evaluate tsunami hazard near the Kuril Island

A sequence of computer experiments is used to study questions concerning the tsunami problem as a quantitative estimate of tsunami danger, detailed geographical tsunami classification, determination of the parameters of critical tsunami waves, and the conditions of their development. We call a wave critical, if its impact on the coast is most hazardous.Using the Middle Kuril Island as an example, we present the results of a computer experiment which includes determining the wavefields on the shelf and estimating the effects connected with the deep-water Bussol and Diana Straits.Numerical simulation of tsunami waves of different sources permits the assessment of the extent of tsunami danger in different areas of the coastal zone of Simushir Island, depending on the location of the focus zone and their geometry.The major singularities of the wavefield arise in the zones of the deep-water straits. The distribution of the amplification factors is determined by both the global parameters of the wavefields and the local properties of individual harbours. The results obtained for a particular harbour in the northern part of Simushir Island, formed the basis for the quantitative estimate of tsunami danger for this area.     

A New Theropod Dinosaur (Theropoda,Dromaeosauridae) from the Late Cretaceous of Tajikistan

Doklady Earth Sciences - A new dromaeosaurid theropod dinosaur, Kansaignathus sogdianus gen. et sp. nov., is described based on a dentary from the Yalovach Formation (Santonian) at Kansai locality...     

Influence of alcohols on the extraction of cerium(IV) by Aliquat-336 in kerosene

Tricaprylmethylammonium chloride (Aliquat-336) diluted with kerosene was used to extract cerium(IV) from nitric acid medium. Various alcohols were used as modifiers to overcome the third phase problem. The different parameters affecting the extraction process including nitric, nitrate, hydrogen ion, extractant and metal concentrations as well as the temperature were separately investigated. The effect of the investigated alcohols on the extraction process was also studied in detail at two different concentrations and correlated to their physical constants. Based on the obtained results, the extraction equilibrium was deduced and the optimum conditions for the extraction of cerium(IV) were proposed. The method was tested and applied to the separation of cerium from the hydrous oxide cake resulting from monazite sand.     

A Local Anomaly of the Stress State of the Earth’s Crust before the Strong Earthquake (M = 7.1) of July 5, 2019, in the Area of Ridgecrest (Southern California)

Doklady Earth Sciences - The evolution of the stress–strain state of the Earth’s crust in Southern California during the preparation period (from January 1, 2019 until August 15, 2019)...     

Assessing scleractinian corals as recorders for paleo-pH: Empirical calibration and vital effects

Laboratory experiments on the branching, symbiont-bearing coral genus Porites and Acropora have been carried out to determine the dependence of the skeletal boron isotopic composition (δ¹¹B) on the pH of seawater. The results show a clear relationship similar to previously established empirical calibrations for planktonic foraminifera and inorganic calcite. A −0.6‰ offset exists between P. cylindrica and A. nobilis which is systematic over the pH range of 7.7-8.2. To test whether the δ¹¹B of coral skeletons changes with physiological processes such as photosynthesis and respiration, corals were grown along a depth transect in their natural environment and under controlled conditions in the laboratory at varying light intensities and food supply. Although we also observe an isotopic offset between P. compressa and Montipora verrucosa, neither experimental treatment systematically changed the δ¹¹B of the two species. These findings are encouraging for using the boron isotope paleo-pH proxy in corals, because it appears that seawater pH is the dominant control on the boron isotopic composition in corals.     

OBSERVATIONS ON THE QUATERNARY GEOLOGY OF THE LADAKH RANGE, NORTHWEST INDIAN HIMALAYA

OBSERVATIONS ON THE QUATERNARY GEOLOGY OF THE LADAKH RANGE, NORTHWEST INDIAN HIMALAYA