E. M. Galimov

Analytical results for the material of the Chelyabinsk meteorite

This paper presents the results of the mineralogical, petrographic, elemental, and isotopic analysis of the Chelyabinsk meteorite and their geochemical interpretation. It was shown that the meteorite can be assigned to LL5-group ordinary chondrites and underwent moderate shock metamorphism (stage S4). The Chelyabinsk meteorite contains a significant fraction (approximately one-third by volume) of shock-melted material similar in composition to the main volume of the meteorite. The results of isotopic analysis suggest that the history of meteorite formation included an impact event approximately 290 Ma ago.

Phobos sample return mission: Scientific substantiation

The goals and the main scientific objectives of the Phobos-Grunt space mission are considered. The content of the investigations of the main task of the mission—to return a sample of Phobos material to the Earth in order to answer the question about the origin of this satellite of Mars and to reconstruct its history—is discussed.

Source of hydrocarbons in the supergiant Romashkino oilfield (Tatarstan): Recharge from the crystalline basement or source sediments?

Romashkino is a supergiant oilfield in Tatarstan with reserves of more than 5 billion tons of oil. The relatively small thickness of the sedimentary cover on the South Tatar arch and the location of Devonian producing beds directly above the crystalline basement were used as arguments for speculations about a deep source of hydrocarbons and a role of the basement as a conduit for fluids. It was found that several wells at Romashkino exhibit “anomalous” behavior characterized by a steady and, sometimes, increasing production, which was interpreted as an indication of recharge from below along basement faults. We present the results of isotope and geochemical studies of crude oils from the sedimentary units of Tatarstan, oils from “anomalous” wells at the Romashkino field, and organic matter from both sedimentary and basement rocks. The results of isotope analysis (comparison of carbon isotopic compositions in the fractions) revealed a genetic link between oils from the sedimentary rocks and organic matter from the Late Devonian Domanik-type facies beds. Because the organic matter within the South Tatar arch does not reach sufficient maturity for hydrocarbon generation, we supposed that sediments of similar type and age (Domanik facies) in the deeper parts of the Ural foredeep and Buzuluk depression could be a likely source of hydrocarbons in this area. The study of oils from “anomalous” wells revealed their close similarity to the other oils from the sedimentary cover. The analysis of the composition of hydrocarbons, which are present in trace amounts in basement rocks, provided no evidence to support the role of deep abiogenic hydrocarbons in recharging oil pools at Romashkino and other fields of Tatarstan.

Hydrocarbons from a volcanic area. Oil seeps in the Uzon caldera, Kamchatka

The isotope and hydrocarbon compositions of oil seeps in the caldera of Uzon Volcano were investigated. An experiment was conducted to simulate the thermal hydrolysis of biota in the hot springs of the caldera, which is considered as a source of carbon for the oil seeps. The same methods were applied to investigate petroleum condensate and thermal gases (CH4 and CO2) from a well in the Bogachevka field adjacent to the Uzon caldera. The measured carbon isotope composition of oils from the Uzon caldera (δ13C of −31.24 and −31.47‰) is typical of oils derived from biological materials of mostly bacterial origin. The low content of tricyclic terpanes, which is a qualitative oil maturity parameter, indicates that the oil maturity of the Uzon seeps is low. In the gas samples, the δ13C of CO2 ranges from −6.5 to −0.18‰ averaging approximately −2.8‰. The δ13C of methane is from −30.13 to −19.03‰ averaging approximately −24.0‰. A difference was detected between the isotopic fractionation characteristics of naphtides from the Uzon caldera and products of the thermal hydrolysis of biota. In turn, the isotopic fractionation characteristic of thermally hydrolyzed biota appeared to be similar to the proportion of the isotopic compositions of the respective fractions of Bogachevka oil. The identical isotopic diagrams of the Bogachevka oil and the hydrothermally transformed biota confirm the biogenic nature of the Bogachevka oil. Hydrocarbons from the Uzon caldera (Kamchatka) are mainly products of the hydrothermal transformation of the biomass of microorganisms and plant remains in the zone of thermal water circulation.

The Nature of Volatiles in the Lunar Regolith

Layer-by-layer analysis of the fine fraction of Luna-16 sample L1635 by X-ray photoelectron spectroscopy (XPS) revealed a zonal structure of its constituent particles. The outer zone, to a depth of 1200 Å, is enriched with Si and Fe and depleted in refractory elements Mg, Ca, and Al as compared to the bulk composition of the sample. The second zone, in the depth range from 1200 to 4500 Å, is of very unusual composition: it is enriched with carbon (up to 60 at. %) and zinc (up to 4 at. %) and contains some other volatiles. The lower zone, at depths from 4500 to 7000 Å, is composed of a silicate material; however, the concentrations of refractory elements are noticeably higher than those in the near-surface layer. There is a difference in structural and chemical characteristics of most of the elements between different zones. These findings point to the exogenous origin of the enrichment of the studied sample with volatiles and are related to the fall of a volatile-rich body (comet or carbonaceous chondrite) on the Moon. The hypothesis of the cometary (carbonaceous-chondrite) impact explains the main patterns of the volatile distribution in the lunar regolith, including the formation of green and orange glasses from Apollo 15 and 17 collections.

Study of the organic matter in the rocks of the crystalline basement and weathering mantle of Tatarstan

This paper is dedicated to study of the rocks of crystalline basement and weathering mantle taken from several parametric boreholes at the territory of Tatarstan Republic. Optical-microscopy in combination with methods of organic geochemistry, including isotope analysis, revealed a migration nature of the organic matter of the studied rocks from oil-source beds of the Devonian domanikoid-facies deposits.

Microcrystalline diamonds in the oceanic lithosphere and their nature

The carbon isotope composition of microdiamonds found in products of the Tolbachik Volcano eruption, Kamchatka (porous lavas and ash), was studied. The isotope composition of microdiamonds (with an average value of δ13C =–25.05‰) is close to that of microsized carbon particles in lavas (from–28.9 to–25.3‰). The general peculiarities of the diamond-forming environment include (1) no evidence for high pressure in the medium; (2) a reduced environment; and (3) mineralogical evidence for the presence of a fluid. The geochemical data characterizing the type of diamonds studied allow us to suggest that they were formed in accordance with the mechanism of diamond synthesis during cavitation in a rapidly migrating fluid, which was suggested by E.M. Galimov.

Role of low solar luminosity in the history of the biosphere

It was shown that the history of the biosphere is closely related to processes caused by low solar luminosity. Solar radiation is insufficient to maintain the Earth’s surface temperature above the freezing point of water. Positive temperatures are kept owing to the presence of greenhouse gases in the atmosphere: CO2, CH4, and others. Certain stages in the development of the biosphere and climate are related to these effects. Methane was the main carbon-bearing gas in the primordial atmosphere. It compensated the low solar luminosity. Life originated under the reduced conditions of the early Earth. Methane-producing biota was formed. Methane remained to be the main greenhouse gas in the Archean. The release of molecular oxygen into the atmosphere 2.4 Ga ago resulted in the disruption of the established mechanism of the compensation of the low solar luminosity. Methane ceased to cause a significant greenhouse effect, and the content of carbon dioxide was insufficient to play this role. A global glaciation began and had lasted for approximately 200 million years. However, the increasing CO2 content in the atmosphere reached eventually a level sufficient for the compensation for the low solar luminosity. The glaciation period came to an end. Simultaneously, a conflict arose between the role of CO2 as a gas controlling the thermal regime of the planet and as an initial material for biota production. As long as the resource of biotic carbon was inferior to that of atmospheric CO2, the uptake of atmospheric CO2 related to sporadic increases in biologic production was insufficient for a significant change in the thermal regime. This was the reason for a long-term climate stabilization for 1.5 billion years. By 0.8 Ga, the resource of oceanic biota reached the level at which variations in the uptake of atmospheric CO2 related to variations in the production of organic and carbonate carbon became comparable with the resource of atmospheric CO2. Since then, an oscillatory equilibrium has been established between the intensity of biota development and climate-controlling CO2 content in the atmosphere. Glaciation and warming periods have alternated. These changes were triggered by various geologic events: intensification or attenuation of volcanism; growth, breakup, or migration of continents; large-scale magmatism; etc. A new relation between atmospheric CO2 and biotic carbon was established in response to the emergence of terrestrial biota and the appearance of massive buffers of organic carbon on land. The interrelation of the biosphere and climate changed.

Intentions and failures. Fundamental space investigations in Russia of the last twenty years. Twenty years of fruitless efforts

This contribution provides the history of Russian planetary exploration over the past 15–20 years. Despite particular interesting ideas and accomplishments, little encouragement can be derived from those activities. Over these years, no lunar and planetary missions took place in Russia, whereas the United States, European countries, China, Japan, and India sent dozens of spacecrafts, which allowed them to make considerable progress in the exploration of the solar system. Despite hefty funding, none of three deep space astrophysical observatories of the Spektr series was launched. The main reasons for this—incompetence and lack of responsibility—are just part of an overall disturbing trend, which can be observed not only in space activities but also in many other parts of our life. Therefore, this book is not only targeted at specialists from the space sector and science, but will also be useful to many readers who are interested in the situation in their own country. The author hopes this book will help those who want to learn lessons from painful failures and provide basis for improving management practices in the future.

Diamonds in the products of the 2012–2013 Tolbachik eruption (Kamchatka) and mechanism of their formation

The origin of diamonds in the lava and ash of the recent Tolbachik eruption of 2012–2013 (Kamchatka) is enigmatic. The mineralogy of the host rocks provides no evidence for the existence of the high pressure that is necessary for diamond formation. The analysis of carbon isotope systematics showed a similarity between the diamonds and dispersed carbon from the Tolbachik lava, which could serve as a primary material for diamond synthesis. There are grounds to believe that the formation of Tolbachik diamonds was related to fluid dynamics. Based on the obtained results, it was suggested that Tolbachik microdiamonds were formed as a result of cavitation during the rapid movement of volcanic fluid. The possibility of cavitation-induced diamond formation was previously theoretically substantiated by us and confirmed experimentally. During cavitation, ultrahigh pressure is generated locally (in collapsing bubbles), while the external pressure is not critical for diamond synthesis. The conditions of the occurrence of cavitation are rather common in geologic processes. Therefore, microdiamonds of such an origin may be much more abundant in nature than was supposed previously.