geological period
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2021 ◽  
Vol 2131 (4) ◽  
pp. 042049
Author(s):  
D Klimov

Abstract In the light of the eternal discussion regarding the sources of hydrocarbons for the initial oil and gas-forming substance, it is possible to recognize the legitimacy of both organic matter, which is confirmed by the biogenic theory of the origin of oil, and deep gases, declared by supporters of the theory of the inorganic concept, referring to the extraordinary richness of hydrocarbons in the mantle. But, the catagenic stage, the process of obtaining oil from the initial substance, in which the primary carbonaceous substance (often under such hypothetical concepts as “micron-oil”, “fluids”) passes into hydrocarbons in the form of oil deposits, causes no less scientific interest and also insufficiently studied. The author sees it as fair to attempt to put emphasis on predominantly geodynamic conditions, tectonic stresses, physico-chemical and thermobaric conditions, the generation of hydrocarbons, on the basis of the synthesis of hydrocarbons in any geological period. The article proposes the author’s chemical model describing the low-temperature polycondensation synthesis of hydrocarbons from water and carbon dioxide in the process of mechanical reactions on the surface of a rock model.


2021 ◽  
Vol 12 (07) ◽  
pp. 26-30
Author(s):  
Səlminaz Cavanşir qızı Mahmudova ◽  

The article discusses the existing inland water resources in Azerbaijan. As a result of scientific research, it is known that all the rivers of Azerbaijan belong to the Caspian Sea, which is an inland basin, and the number is 8359. Drawing attention to the formation of Azerbaijan's internal water resources, the author notes that these waters were formed over a long geological period, depending on climatic and relief conditions. The article notes that the rivers, which are considered to be the most important element of sand water, are divided into three groups according to the source of food and the direction of flow. It is grouped as a temporary river flowing directly into the Caspian Sea, belonging to the Kura River basin and Absheron-Gobustan. When discussing the reasons for the formation of some rivers, it is shown that the rivers flowing through the area formed canyon-shaped valleys as they passed through the soft, easily washed rocks of the Cretaceous and Jurassic periods of the Mesozoic era. The Tangi gorge, a tributary of the Valvalachay, was formed for this reason. In addition to rivers, natural water resources include lakes. Depending on the natural and geographical conditions of the area where the lakes are located, the origin of the depression, they are subject to various physicochemical and hydrological features. Key words: Azerbaijan, geographical location, water resources, rivers, lakes, river mouth, source of water resources


Author(s):  
Daiqing Yin ◽  
RuRu Zhou ◽  
Mengxin Yin ◽  
Yue Chen ◽  
Shixia Xu ◽  
...  

Abstract Arylalkylamine N-acetyltransferase (AANAT) plays a crucial role in synchronizing internal biological functions to circadian and circannual changes. Generally speaking, only one copy of AANAT gene has been found in mammals, however, three independent duplications of this gene were detected in several cetartiodactyl lineages (i.e., Suidae, Hippopotamidae, and Pecora) that originated in the middle Eocene, a geological period characterized with the increased climate seasonality. Lineage-specific expansions of AANAT and the associated functional enhancement in these lineages strongly suggest an improvement in regulating photoperiodic response to adapt to seasonal climate changes. In contrast, independent inactivating mutations or deletions of the AANAT locus were identified in the four pineal-deficient clades (cetaceans, sirenians, xenarthrans, and pangolins). Loss of AANAT function in cetaceans and sirenians could disrupt the sleep-promoting effects of pineal melatonin, which might contribute to increasing wakefulness, adapting these clades to underwater sleep. The absence of AANAT and pineal glands in xenarthrans and pangolins may be associated with their body temperature maintenance. The present work demonstrates a far more complex and intriguing evolutionary pattern and functional diversity of mammalian AANAT genes than previously thought, and provides further evidence for understanding AANAT evolution as driven by rhythmic adaptations in mammals.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10647
Author(s):  
Valentin Fischer ◽  
Robert Weis ◽  
Ben Thuy

Even though a handful of long-lived reptilian clades dominated Mesozoic marine ecosystems, several biotic turnovers drastically changed the taxonomic composition of these communities. A seemingly slow paced, within-geological period turnover took place across the Early–Middle Jurassic transition. This turnover saw the demise of early neoichthyosaurians, rhomaleosaurid plesiosaurians and early plesiosauroids in favour of ophthalmosaurid ichthyosaurians and cryptoclidid and pliosaurid plesiosaurians, clades that will dominate the Late Jurassic and, for two of them, the entire Early Cretaceous as well. The fossil record of this turnover is however extremely poor and this change of dominance appears to be spread across the entire middle Toarcian–Bathonian interval. We describe a series of ichthyosaurian and plesiosaurian specimens from successive geological formations in Luxembourg and Belgium that detail the evolution of marine reptile assemblages across the Early–Middle Jurassic transition within a single area, the Belgo–Luxembourgian sub-basin. These fossils reveal the continuing dominance of large rhomaleosaurid plesiosaurians, microcleidid plesiosaurians and Temnodontosaurus-like ichthyosaurians up to the latest Toarcian, indicating that the structuration of the upper tier of Western Europe marine ecosystems remained essentially constant up to the very end of the Early Jurassic. These fossils also suddenly record ophthalmosaurid ichthyosaurians and cryptoclidid plesiosaurians by the early Bajocian. These results from a geographically-restricted area provide a clearer picture of the shape of the marine reptile turnover occurring at the early–Middle Jurassic transition. This event appears restricted to the sole Aalenian stage, reducing the uncertainty of its duration, at least for ichthyosaurians and plesiosaurians, to 4 instead of 14 million years.


Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 823 ◽  
Author(s):  
Anatoliy R. Galamay ◽  
Krzysztof Bukowski ◽  
Daria V. Sydor ◽  
Fanwei Meng

Fluid inclusions in halite are widely used in research to determine the conditions of sedimentation in salt basins and reconstruct the chemical composition of seawater during a specific geological period. However, previous preliminary studies of the genetic types of inclusions, considered in the present research project, have not received due attention. Consequently, we decided to take into account the main distinguishing features of fluid inclusions in halite, belonging to various genetic types. The ultramicrochemical analysis (UMCA) method is one of the several methods that are used for the quantitative determination of the chemical composition of the primary fluid inclusions in halite. We have upgraded that technique, and that allowed us to reduce the analytical error rates of each component determination. The error rates were calculated in the study of Ca-rich and SO4-rich types of natural sedimentary brines.


Author(s):  
José Gomes dos Santos

The growing interest related to the proposal of formal definition of a new geological period that has being called “Anthropocene” has introduced a buzzing dynamics in the scientific community, but its conduct is perhaps due to various interests involved in a discussion that has long surpassed the contours of the so-called “Geosciences”. Themes such as “Climate Change or Drift”, “Global Warming”, “Massive Extinction of Species” and “Loss of bio and geodiversity”, among others, are the wheel of a geomorphogenetic dynamics of anthropocentric origin, which leads the debate. But are the conditions for the formal establishment of a new morphosedimentary cycle following the Meghalayanian (Upper Holocene) Age? This work pursues a line of thought that seeks to answer these and other questions, based on the official position of the institutes that have the scientific competence for the formalization under consideration, and the formal criteria that should be considered for this purpose.


2020 ◽  

The landscape of the Netherlands has been changing constantly since the end of the last ice age, some 11,700 years ago. Where we walk today was once a polar desert, a river delta or a shallow sea. The end of the last ice age marked the beginning of a new geological period - the Holocene, the relatively warm geological epoch in which we are still living today. The Atlas of the Holocene Netherlands contains special maps, supplemented by archaeological and historical information. These maps show the geographical situation for thirteen different points in time since the last ice age, based on tens of thousands of drill samples and the latest geological, soil and archaeological research. This magnificent atlas also paints a surprising picture of the position we humans have occupied in the landscape. It addresses such questions as: How did we take advantage of the opportunities offered by the landscape? And how did we mould the landscape to suit our own purposes? The Atlas of the Holocene Netherlands will change once and for all the way you look at the Dutch landscape.


2020 ◽  
Vol 206 ◽  
pp. 01015
Author(s):  
Yaohuang Li

During a certain geological period, the sea surface is at the current elevation of about 4746-4755 meters. When the sea surface is about 4746-4755 meters above sea level, the Namtso region of Tibet is a lagoon in the sea. The sea surface was kept stable at the above location for a long time, and a lot of sea erosion landforms were generated on the coast. The ancient sea erosion caves, sea erosion pillars, sea erosion arch bridges, sea erosion headlands, sea erosion headlands, sea erosion cliffs, sea erosion platforms and other various ancient sea erosion micro-landforms are well preserved on the banks of Namtso Lake. It is a unique and natural ancient coastal landscape park in the world


2019 ◽  
Vol 41 (1) ◽  
pp. 40-50
Author(s):  
Claire Colebrook

There is something more catastrophic than the end of the world, especially when ‘world’ is understood as the horizon of meaning and expectation that has composed the West. If the Anthropocene is the geological period marking the point at which the earth as a living system has been altered by ‘anthropos,’ the Trumpocene marks the twenty-first-century recognition that the destruction of the planet has occurred by way of racial violence, slavery and annihilation. Rather than saving the world, recognizing the Trumpocene demands that we think about destroying the barbarism that has marked the earth.


Author(s):  
Jan Holmgren

Human culture is presently setting a disastrous mark on planet Earth, overexploiting its resources, causing global warming, causing mass extinctions. We appear already to be in a new geological period, the Anthropocene. The natural sciences are crucial for the understanding of those processes. Equally important are decisions in human culture to act on the large challenges in humane and rational ways. Whitehead's evolutionary Philosophy of Organism, with the introduction of atomic microfeels, inspires a coherent cosmology characterized by the basic position of human consciousness. The humane aspects (pre-physical, metaphysical) of human culture (e.g. the humanities, the religions, the arts) are shown to be importantly causal in the universe. Human empathy and altruism (loving attitudes) combined with rationalism and truthfulness must be enhanced as central ambitions in human societies, not least in areas like politics and economy. The suggested worldview, accepting complementarity, is named multi-aspect monism (MAM).


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