No 3 (2024)

This work is devoted to typification, study of the compositional features and properties of hydrothermal zeolites of the Yagodninskoe deposit (Kamchatka Krai), formed over volcanic rocks. To carry out the research, X-ray phase and X-ray fluorescence analyses, optical and scanning electron microscopy were used; the specific surface area, pore size distribution, and cation exchange capacity of zeolites were determined. As a result of the research, 4 main types of rocks found at the deposit were identified: original unaltered perlites, zeolites themselves, zeolitized tuffs, and weakly zeolitized tuff breccias. The content of zeolite group minerals reaches 70%, and are mainly represented by clinoptilolite and to a lesser extent mordenite, stilbite and heulandite. Zeolites are of the alkaline type, the cation exchange capacity of which is 205.9 mEq/100 g. It was established that the formation of zeolites occurred mainly in perlites and tuff breccias. It is noted that the zeolites of the Yagodninskoye deposit have high quality raw materials and are the promising object for further development.

We analyzed sets of published data on the composition of glasses from melt inclusions in minerals of volcanics from the Eastern Volcanic Front and Sredinny Range of Kamchatka. A significant difference was revealed between the distribution of silica contents in the rocks and melts: intermediate compositions are most common among the rocks, whereas the melts are dominantly silicic. The distribution of major and trace element was analyzed. It was shown that the contents of some elements are environment-specific (e. g., Nb and light REE). We distinguished trace element ratios in melts that most strongly correlate with the geodynamic setting.

Assessment of the degree of tectonic fragmentation of the upper part of the lithosphere, according to the method of Yu.V. Nechaev [2010] is based on calculations of the specific length of lineaments. On the example of three different regions – the Northwestern Caucasus, the Voronezh anteclise, and the Malko-Petropavlovskaya zone of Kamchatka – we have tested the possibility of using other morphometric parameters: the specific lengths of “weak” zones, elongation lines and streams, as well as the Gaussian curvature of the relief. Their anomalies are confined to seismically active areas and areas of manifestation of hydrothermal-magmatic activity. It is shown that the most informative are 3D models of tectonic fragmentation, built taking into account the specific length of “weak” zones and watercourses.

This article describes the new technique for automatically preparing a noisy seismic record for further analysis using expert information systems. The technique is based on seismogram fingerprints, which, due to their concise but informative pattern, allow the development of a reliable algorithm for finding important noise characteristics. The search for the optimal cutoff frequency for a high-pass filter is especially important under conditions of partial overlap of the signal and noise spectra at a high intensity of the latter. It is precisely this difficult case that this study aims to address. The article analyzes the developed methodology on the example of several hundred registrations of regional earthquakes and explosions. The analysis showed that reliable results can be achieved in more than 90% of cases. In addition to all the problems and limitations of the method, which are an extension of its capabilities, are mentioned. Appendix to the article contains detailed description of the algorithm underlying the method.