Isotope composition of helium in ultrabasic xenoliths from volcanic rocks of Kamchatka

The purpose of this work is to refine our knowledge about the nature of helium with a high abundance of the rare isotope3He(3He/4He= 10−5) discovered in terrestrial volcanic gases in 1968. We will discuss here the results of isotope analyses of helium released by step-wise heating of ultrabasic xenoliths and some volcanic rocks. On the basis of these results, possible sources of3He in the earth due to fission and nuclear reactions are considered critically. The most probable source of the high abundance of3He is shown to be due to the capture and trapping of primordial He by the earth during its formation (primordial helium3He/4He= 3 × 10−4), a small but significant fraction of which has been retained to the present time

Physical development of hockey players aged 13-16 years

Aim. Identify the age features of hockey players aged 13-16 years old physical development. Material and methods. Elite hockey players (n = 83, age - 13-16 years) were surveyed. Standard anthropometric methods for measuring length and body weight were used. The body mass index (BMI) was calculated. Results. The average value of the body length of hockey players did not differ from peers, who do not engage in sports. The cental distribution of the absolute values of the indicator relative to nomograms has been shifted to the right. Most hockey players had average body lengths. The excess of the average body weight of hockey players was recorded in comparison with the average population values. The cental distribution of absolute values was characterized by a significant shift to the right (range 3% -90% percentile). Most hockey players had a body weight “above average” (55-66%). The group of athletes with body weight and BMI “below average” was 6% (age from 13 to 15 years). Conclusions. The physical development of elite hockey players is characterized by an average body length with a tendency to shift to values *above average*. The proportion of hockey players with mean body lengths below the mid-population is very small. Elite hockey players are characterized by large body weight and BMI compared to peers who do not engage in sports. As the age increases from the morphological criteria, the body weight and BMI have the greatest value for the hockey player’s success in sports selection

Recent hydrothermal systems of Kamchatka

Study of the largest manifestations of the recent hydrothermal activity in Uzon-Semyachik, Pauzhetka-Kambalny and other regions in Kamchatka enable us to conclude: in the area of recent volcanism characterized by a general increase of conductive heat flow, some regions can be distinguished with an especially intense geothermal regime specified by an additional supply of heat by deep fluids. Within such anomalies the formation of hydrothermal systems can be observed. Recent hydrothermal systems of Kamchatka are natural hydrodynamic systems belonging to the type of small artesian basins and artesian slopes having porous-bedded, fissure-bedded and more seldom fissure-veined permeability and containing high-temperature underground waters. They are associated with volcano-tectonic grabens and circular depressions filled with a series of tufaceous material of mainly acid composition and two-membered structure. Localization of certain thermal manifestations within the systems is determined by disjunctive tectonics and outflows of thermal waters to the surface. The same factors are responsible for the position of the recharge areas of the systems with infiltration waters forming the main mass of their water reserves. Usual hydrodynamic methods can be used for a quantitative estimation of these reserves. Heat recharge of the systems is realized by the supply of an over-critical fluid. This is confirmed by hydrogeothermal data, similarity of the chemical composition of high temperature hydrothermal water and their thermo-physical parameters. Manifestations of hydrothermal activity do not reveal any connection with recent andesite-basaltic volcanism of Kamchatka; on the contrary, they are associated with the acid volcanism of the Middle and Upper Pleistocene stage of its geological history, testifying to their genetic similarity. Hydrothermal activity is one of the manifestations of the general geothermal activity of the interior. It is closely related, in time and space, to a certain stage of the volcano-plutonic process and tectonic evolution of mobile belts. The perspectives of obtaining heat and electric energy from hydrothermal systems are considered