Chemical Evolution of Planet Substance at Impact
Experimental Research of Chemical Evolution of Substance of the Moon and Other Bodies of Solar System by Methods of High-Speed Shock Modeling
Tech Area / Field
- SAT-EXP/Extraterrestrial Exploration/Space, Aircraft and Surface Transportation
- OBS-NAT/Natural Resources and Earth Sciences/Other Basic Sciences
3 Approved without Funding
VNIIEF, Russia, N. Novgorod reg., Sarov
- IGEM (Geology & Mineralogy), Russia, Moscow\nRussian Academy of Sciences / Institute of Space Research, Russia, Moscow
- University of Vienna/Institute of Geochemistry, Austria, Vienna\nUniversity of Oslo/Department of Geology, Norway, Oslo
Project summaryThe goal of the project is to obtain new experimental information about chemical processes during a hyprvelocity impact of a meteorite into planetary bodies. One of the most important fundamental problems in the investigation of the evolution of planetary bodies is the problem of the trends of chemical evolution of siliceous material during the formation of planets. Initially the solid material of planetary system was forming under conditions of the proto-solar cloud and it is possible to evaluate its composition by investigation of the composition of different types of meteorites. During the formation of planets the initial material have passed a sufficient high-temperature modification since the accretion of planets proceeded by hypervelocity impacts of meteoritic bodies on the surfaces of growing planets with velocities up to 10-20 km/s. Such an impact processing could resulted in the initial differentiation of planetary material. Later on the planetary material have passed further differentiation due to endogenic processes, e.g. volcanism, which have formed the modern state of the planets. At present, the role of initial impact-induced differentiation of planets is not well understood mainly due to the lack of information about the trends of an impact-induced differentiation and its efficiency. The importance of the investigation of the efficiency and trends of an impact-induced differentiation is guided by the fact that all known the most ancient rocks indicate the completion of global differentiation at time before their origin and shift the dating of initial differentiation to the earliest periods of planetary formation and that models of volcanic differentiation experience certain difficulties in explaining of all known observational data.
There is no reliable geochemical models which can discriminate between high-temperature impact-induced differentiation of siliceous material and of not so high-temperature volcanic differentiation, and this in turn terminates the possibility to evaluate the role of impacts in the initial differentiation of the material of the Earth, Moon, and of other planets. The lack of such models is coming from the lack of systematic data about trends of chemical differentiation of siliceous materials during hypervelocity impacts. It is important in this respect that preliminary impact simulation experiments, which were done by the team of project participants, have shown a principal difference of chemical products of impacts compared to volcanic processing.
Experiments on simulation of impact processes include small scale impacts into a semi-infinitive siliceous target with known chemical composition by a known projectile with controlled velocity and a subsequent collection and investigation of condensed and melted products of the impact. The main experimental difficulties of investigation of an impact-induced differentiation are resulted from the difficulty of gaining of impact velocities over 7-8 km/s, which are characteristic to planetary accretion and are necessary for a sufficient vaporization of siliceous material, and also from the difficulty of collection of products of an impact and their separation from contamination, which accompany impact and explosion experiments.
VNIIEF has explosive installations for acceleration of metallic projectiles to velocities over 6 km/s. The use of such installations together with the analytical capabilities of IKI and IGEM is suggestive to become a relatively cheap method of obtaining of new scientific information for the tasks of planetary evolution.
The project has the following aims:
· the adaptation of explosive acceleration installations for the tasks of the modeling of impacts of meteorites into planetary surfaces;
· experimental investigation of chemical effects of an impact of a meteorite into planetary surface and comparison of experimentally derived data with findings in lunar rocks which were delivered by space lunar missions.
Within the project it is anticipated to switch the work of 17 scientists and specialists, who are working in the field of nuclear weapons, to investigations in the field of fundamental problems about the role of impacts in the chemical differentiation of the material of the Moon and other planets of the Solar system. Participants will use their technical and scientific capabilities, which are at their disposal and are sufficient for the completion of the goal of the project:
· explosive acceleration installations and controlling instrumentation on the experimental base of the RFNC-VNIIEF;
· computer codes of the RFNC-VNIIEF for two dimensional calculation of non-stationary two phase gas dynamics of resistive-viscous-plastic systems;
· analytical capabilities of IKI and IGEM RAS for investigation of the chemical composition of the material forming during hypervelocity impacts of silicates.
The data, which will be obtained during the completion of the project, will be a sufficient input into the field of fundamental research of the chemical evolution of the matter of the Solar system due to impact processing.
The project totally corresponds to the aims of ISTC:
· the investigation of the impact-induced chemical transformation of primitive siliceous material in the Solar system is one of the most important fundamental problems of the evolution of planets;
· the experience of specialists of the RFNC-VNIIEF in the performance of experiments using explosive acceleration installations and high-speed control instrumentation together with the experience of specialists of IKI RAS in the detailed chemical analyses of the products of impact vaporization and of specialists of IGEM RAS in the spectroscopic and microscopic analyses of silicates will altogether provide the necessary basis for the successful completion of the project.
For the successful completion of the project we have all the necessary experimental equipment and high-quality specialists of RFNC-VNIIEF, IKI RAS and IGEM RAS.