Vol 517, No 1 (2024)

A numerical modeling of the process of a high-speed impact of a massive asteroid with the Earth’s surface was carried out to study the hypothesis of the meteoritic origin of the impact diamond deposit located in the Popigai River basin. A normal collision of a chondritic asteroid with a layered structure of the Earth’s soil at a speed of 25 km/s is simulated in 2D axisymmetric formulation. The natural carbon deposit layer is located in the near-surface zone of the loaded area. The calculations were carried out using a multidimensional parallel implementation of the finite-size particle-in-cell method. Models of the equations of state of chondrite, quartz and carbon are used to describe the properties of the meteorite and soil material. Thermodynamic parameters of impact compression of soil materials at the initial stages of loading and crater formation processes are obtained.

The evolution of vortices formed when a freely falling drop of a 95% aqueous solution of ethanol, tinted with brilliant green, merges with water in the intrusive mode has been traced by method of high-speed video recording. The drop smoothly flows into the liquid and forms a subducting lenticular intrusion, in which a weakly expressed ring vortex is formed if the potential surface energy is greater than or of the same order as its kinetic energy. Gradually, the intrusion of lighter liquid begins to float up and contracts around the cavern, which takes on a conical shape. From the center of the pointed bottom of the cavity, which has reached its maximum depth, a compact volume containing a light liquid of droplet is pushed into the thickness of the liquid. After the cavern collapses, the primary intrusion spreads along the free surface of the target fluid. In this case, the submerging volume is transformed into a small spherical vortex, which reaches its maximum depth, and then stops and forms a compact secondary intrusion elongated vertically. Next, the central part of the secondary intrusion begins to flow up and gradually transforms into a new ring vortex. As it approaches the free surface, the diameter of the vortex increases. The slowly rising shell of the intrusion forms the bottle-shaped base of the cylindrical trace of the ring vortex, colored with droplet pigment. Changes in the sizes of the main structural components during the evolution of the flow pattern were traced.

For a system of equations in displacements for the Cosserat medium, two variants of representing the general solution through three functions satisfying three independent equations was found, i. e. the system is diagonalized. Expressions for the production of new solutions (symmetry operators) are given. The expressions provides to find new solutions to the original equations by differentiating from any given solution. Some particular solutions was obtained for the cases of plane and antiplane deformation.

Mathematical modeling and investigation of the filtration process of salt water in the sedimentary column, taking into account the phenomenon of osmosis, has been performed. It is shown that the osmotic interaction of salt and fresh water in a sedimentary column containing interlayers and inclusions of poorly permeable rocks (clays, silts, etc.) can lead to the appearance of zones of large pressure anomalies and the destruction of the geomedium. The proposed osmotic mechanism of destruction of the geomedium explains the formation of pockmarks and craters on the surface of passive areas of the crust that do not experience any movements and deformations for a long period of time. This mechanism is an alternative to the common point of view about a polygonal fault system of tectonic nature, on the basis of which marks on the seabed or craters in permafrost areas on land are explained. The mathematical model under study showed that under the conditions under consideration, convection of a solution with closed current lines occurs, similar to gravitational convection.

The prospects for achieving carbon neutrality by economically developed countries (USA, EU, Norway, Canada, Japan and Australia) are studied. An analysis of the structure of energy and land use in these countries is carried out. Scenario estimates of the dynamics of carbon indicators of the economies of the world’s leading countries have been developed.

It is shown that the current rates of decarbonisation and development of the carbon capture and storage industry do not guarantee the achievement of climate neutrality by 2050, even in the world’s leading economies. A central challenge in achieving climate neutrality is the rapid and large-scale deployment of CCS in all its possible manifestations. All of the countries studied, except Japan, have their own capacity to store carbon for more than a hundred years.

To achieve climate neutrality, the leading OECD countries will need to ensure the annual capture of at least 6 billion tons of CO₂ by 2050, which is almost 25 times higher than their current capacities (operating, under construction and under design) Despite the fact that climate change occupies almost a leading place on the global agenda, the actual results of efforts in this area are far from declared. It is no longer realistic to keep warming within 1.5°C, and at the current rate of decarbonization, even by world leaders, the defense of the second critical frontier in 2°C will soon be threatened.