pdf № 353, May

DOI: 10.19110/geov.2024.5.1

In 2004, exploration drilling in the central part of the Nepsko-Botuobinsk anteclise of the Leno-Tunguska oil and gas province of Eastern Siberia at the Danilovsky license area proved the oil content and prospects of the oldest carbonate deposits of the Vendian-Cambrian period. The drilled carbonate complex is characterized by a complex structure and strong variability of structural and textural features in section and laterally. A full cycle of lithological studies, including a description of petrographic sections in combination with X-ray diffraction analysis, and facies analysis of lithological rock types allowed considering the nature of deposits of the productive formation Б5 of the Danilovsky horizon. Cyanobacterial communities in the lifetime position were recorded in the section of the formation, confirming the organogenic skeleton nature of the studied deposits. Septal, chamber and clot forms of communities have been recorded. The results of the genetic analysis of geological and geophysical data formed the basis for a detailed lithological and sedimentological characteristic of the section, which allowed recreating the history of development and forming a sedimentation model of the formation. These studies laid in the basis for the petrophysical model of the formation, the planning of exploratory drilling and the introduction of an optimal development system.

Keywords: Nepa-Botuobinskaya anteclise, Teter formation, dolomites, conceptual model

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DOI: 10.19110/geov.2024.5.2

The Earth, as a system, is characterized by certain average state parameters (density, temperature). These parameters cannot but depend on similar states of internal geospheres (subsystems), which follow the unified law of increasing entropy of the cooling Earth from the center in the direction of the Earth's radius. As a model for assessing the dynamic stability of the Earth's internal geospheres relative to each other, the principle of the golden proportion (golden section) was used with the given parameters of density, temperature, power of the geospheres to the extreme ratios of their states at points (0.618; 1.618; 2.618), which determine the conditions for the stable dynamic equilibrium of the compared parameters of geospheres. And if these relations satisfied the known theoretical, model, geophysical data, then the conclusion was made that the geospheres in the compared parameter relations were in a state close to a stable dynamic equilibrium of the exchange of matter and energy between them. Otherwise, it was recognized that the compared geospheres of the Earth were in a state of either unstable dynamic equilibrium with an assessment of the level of this deviation from the golden numbers, or the known values of the density and temperature of the geospheres, as well as their structure, should be subject to clarification.

Average model estimates of the parameters of the Earth's internal geospheres reach a stable dynamic equilibrium at a level of deviation from the golden numbers of up to 2.72 %. This allows estimating the model duration of the modern geological activity of the Earth for another 124 million years until the formation of a new state of the existing continents. The instability of the dynamic equilibrium of density and temperature of matter is established at the boundaries: continental and oceanic crust; oceanic crust and Golitsin layer; at the boundary between the outer part of the Earth's core and the lower mantle; inside the Earth's core at the level of identified transition zones in the four-layer core model. The presence of spheres with a high core density from 16.05 to 26.45 g/cm³ suggests the stratification of its central part into essentially gold and platinoid.

The presence of instability boundaries in the dynamic state of geospheres is in good agreement with the concept of plate tectonics and with the depths of plume origin. It can be assumed that the relative equilibrium of the internal structure of the Earth will continue for about 124 million years until the beginning of the formation of a new Pangea Proxima, which, according to Cristofor Scotese, will arise in 200 million years.

Keywords: Earth, density, temperature, geosphere, continental and oceanic crust, upper mantle, lower mantle, core, four-layer core model

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DOI: 10.19110/geov.2024.5.3

The article presents modern outlook on overview of the current knowledge about the first findings of fossil resins in the Arctic territory of Denmark (Greenland). On the basis of obscure and fragmentary documents, the history of their study is briefly given,
the primacy of researchers who mentioned fossil resins is noted, locations of fossil resins are given, and the level of their study is assessed. A comparative description of IR-spectra of cedarite (chemawinite), shrauphite, valhovite and resin from Hare Island is given. The similarity of the latter with сedarite is shown.

Keywords: Arctic, Denmark, fossil resins, сedarite (chemawinite), shrauphite, valhovite

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DOI: 10.19110/geov.2024.5.4

The article describes the simulation of ontogenesis of rock mineral aggregate with debatable genesis. Lenses or stokes of weakly deformed rocks are found in the South Urals in the block of kyanite-bearing stratified rocks of the Borisovskiye Sopki, the structure of which corresponds to the structures of igneous rocks. Induced surfaces of joint simultaneous growth are observed in all minerals — muscovite, kyanite, quartz, rutile, pyrite, monazite, xenotime and zircon. This is a paragenesis (eutectics). An interesting fact is that large quartz individuals are saturated with muscovite inclusions, while kyanite, synchronous with them, is free from muscovite inclusions, which is explained by repulsion in the melt-solution of minerals with equally charged surface. The mineral aggregate of the studied rocks lacks morphological signs of metasomatism (metacrystals, pseudomorphs, shadows of previous solid bodies) and recrystallization. This indicates magmatic genesis of the studied quartz-kyanite-muscovite rocks.

Keywords: mica, igneous rock, quartz, kyanite, muscovite, induction surfaces, Southern Urals

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