3. Sedimentary rocks

Author(s):  
Jan Zalasiewicz

The Earth has the greatest abundance and variety of sedimentary strata in our star system, dating back some 3.8 billion years. ‘Sedimentary rocks’ describes the processes that create different types of sedimentary rocks, which form a key guideline in reconstructing Earth’s history. Particles are created by both physical and chemical weathering. These particles are then moved by different modes of transport and sorted by size, which affect the resulting sedimentary rock. Sedimentary layers can remain as soft muds or loose sands for millions of years, but most buried sedimentary layers harden and turn into rock, under the combined effects of increasing heat and pressure, and of changes in chemical environment.

2019 ◽  
Author(s):  
Maria L. Leonard ◽  
◽  
Rachel M. Kelk ◽  
Dori J. Farthing

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 479
Author(s):  
Irina Sokolik

This Special Issue aims at addressing the recent developments towards improving our understanding of the diverse radiative impact of different types of aerosols and clouds [...]


Geology ◽  
2021 ◽  
Author(s):  
Iain K. Pitcairn ◽  
Nikolaos Leventis ◽  
Georges Beaudoin ◽  
Stephane Faure ◽  
Carl Guilmette ◽  
...  

The sources of metals enriched in Archean orogenic gold deposits have long been debated. Metasedimentary rocks, which are generally accepted as the main metal source in Phanerozoic deposits, are less abundant in Archean greenstone belts and commonly discounted as a viable metal source for Archean deposits. We report ultralow-detection-limit gold and trace-element concentrations from a suite of metamorphosed sedimentary rocks from the Abitibi belt and Pontiac subprovince, Superior Province, Canada. Systematic decreases in the Au content with increasing metamorphic grade indicate that Au was mobilized during prograde metamorphism. Mass balance calculations show that over 10 t of Au, 30,000 t of As, and 600 t of Sb were mobilized from 1 km3 of Pontiac subprovince sedimentary rock metamorphosed to the sillimanite metamorphic zone. The total gold resource in orogenic gold deposits in the southern Abitibi belt (7500 t Au) is only 3% of the Au mobilized from the estimated total volume of high-metamorphic-grade Pontiac sedimentary rock in the region (25,000 km3), indicating that sedimentary rocks are a major contributor of metals to the orogenic gold deposits in the southern Abitibi belt.


1949 ◽  
Vol 39 (3) ◽  
pp. 205-218
Author(s):  
S. K. Chakrabarty

Summary The equation of motion of the seismometer and the galvanometer in an electromagnetic seismograph has been derived in the most general form taking into consideration all the forces acting on the system except that produced by hysteresis. A general solution has been derived assuming that the earth or the seismometer frame is subjected to a sustained simple harmonic motion, and expressions for both the transient and the steady term in the solution have been given. The results for the particular case when the seismograph satisfies the Galitzin conditions can easily be deduced from the results given in the present paper. The results can now be used to study the response characteristics of all electromagnetic seismographs, whether they satisfy the Galitzin conditions or not, and will thus give an accurate theoretical picture of the response also of seismographs used for the study of “local earthquakes” and “microseisms” which do not in general obey the Galitzin conditions. The results obtained can also be used to get analytically the response of the seismographs for different types of earth motion from the very beginning, and not only after the transient term has disappeared. The theory of the response to simple tests used to determine the dynamic magnification of any seismograph and also to determine and check regularly the instrumental constants of the seismographs has been worked out. The results obtained can also be used for ascertaining the proper values of the instrumental constants suitable for the various purposes for which the seismographs are to be used.


2021 ◽  
Vol 21 (2) ◽  
Author(s):  
Kamalasan Prathap- Mathan ◽  
Joseph Babila- Jasmine ◽  
Muthukumar Thilagavathi

Water is the most abundant and non-renewable resource in the earth, which play an important role in all living organisms. A study on physiochemical parameters of Manur, Vallanadu and Sundarapandiapatinam ponds from Tirunelveli, Thootukudi and Ramanathapuram districts of Tamil Nadu, India, has addressed the seasonal changes. During the month of January to April samples from Manur was chemically portable, Vallanadu sample was physically portable, Sundarapandiapatinam samples were physically and chemically not portable. During the month of May to August Vallanadu and Manur samples were portable by its physical and chemical examination, Sundarapandiapatinam samples were non portable by its physiochemical property. September to December the samples from all the three ponds were non portable because of exceeding the permissible limit. All the samples were bacteriologically unsafe in nature because of its microbial contamination. This implies the water bodies are not fit for domestic and drinking purpose, thus proper management has to be done by the society and implement government guidelines to save the natural resources from manmade activities.


2014 ◽  
Vol 14 ◽  
pp. 87-147 ◽  
Author(s):  
Florentina Badalanova Geller

Cosmogonies and mythopoesis in the Balkans and beyondCompared and contrasted in this article are three different types of accounts dealing with the cosmogonic and eschatological themes employed in Slavonic and Balkan oral tradition, para-Biblical literature and modern poetry. The focus of analysis is the cluster of motifs attested in the creation narrative of the apocryphal Legend of the Sea of Tiberias. Two versions are examined: the South-Slavonic one discovered in 1845 by V. Grigorovich in the Monastery of Slepche, and the 18th century Russian account from MS № 21.11.3 (fols. 3a–5b) from the Archaeographic Department of the Library of the Academy of Sciences [Библиотека Академии наук, Рукописный отдел] in St. Petersburg, composed most probably by an Old Believer; this manuscript is published here for the first time. Folklore counterparts of the apocryphal Legend of the Sea of Tiberias are treated, with special emphasis on the oral narratives from the Bulgarian diaspora in Bessarabia (God and the Devil Create the World Amicably but then Fall Out). Finally, a poem of the 20th century Bulgarian intellectual Pencho Slaveykov [Пенчо Славейков] from his anthology “On the Island of the Blessed” is discussed; the poem, entitled How God willed the Earth to come to be and what did Satanail do after that? was designated by Slaveykov himself as “a legend of the Bogomils”, and blended within his lyrics are dualistic themes and motifs attested in vernacular Christianity, with the hallmark of Haeresis Bulgarica. Kosmogonie i mitopoetyki na Bałkanach i nie tylkoW artykule zostały porównane trzy typy narracji zawierających wątki kosmogoniczne i eschatologiczne, które funkcjonują w słowiańskiej i bałkańskiej tradycji ustnej, literaturze parabiblijnej oraz poezji doby modernizmu. Przedmiotem uwagi stała się grupa motywów poświadczonych w narracji o stworzeniu, znanej z Legendy o Morzu Tyberiadzkim. Analizom poddane zostały dwie wersje: południowosłowiańska, odkryta w 1845 roku przez W. Grigorowicza w Monastyrze w Slepče, oraz ruska – z XVIII wieku, znajdująca się w kodeksie MS № 21.11.3 (fols. 3a–5b), przechowywanym w Oddziale Rękopisów Biblioteki Akademii Nauk w Sankt Petersburgu – skomponowana najprawdopodobniej w środowisku staroobrzędowców (rękopis ten jest tu publikowany po raz pierwszy). Następnie przeprowadzona została analiza odpowiedników folklorystycznych apokryficznej Legendy o Morzu Tyberiadzkim, ze szczegól­nym uwzględnieniem narracji ustnych funkcjonujących w bułgarskiej diasporze w Besarabii (Bóg i Diabeł tworzą świat w przyjaźni ale potem stają się wrogami). Na końcu został poddany interpretacji poemat z XX wieku autorstwa bułgarskiego modernisty Penczo Sławejkowa [Пенчо Славейков] z antologii Na wyspie błogosławionych [На острова на блажените]; poemat ten, zatytułowany Jak Bóg zezwolił, aby powstała ziemia i co potem uczynił Satanael?, został nazwany przez samego autora „legendą Bogomiłów”, i skompilowany w jego tekstach z dualistycznymi motywami występującymi w chrześcijaństwie tego regionu, a rozpoznawa­nymi jako haeresis bulgarica.


Author(s):  
Pranvera Breznica ◽  
Rozafa Koliqi ◽  
Arlinda Daka

Upon entering into the biological environments, the surface of the nanoparticles is immediately coated with proteins and form the so-called a protein corona due to which a nanoparticle changes its "synthetic" identity to a new "biological" identity. Different types of nanoparticles have different protein binding profiles, which is why they have different protein corona composition and therefore it cannot be said that there is a universal protein corona. The composition and amount of protein in the corona depends on the physical and chemical characteristics of the nanoparticles, the type of biological medium and the exposure time. Protein corona increases the diameter but also changes the composition of the surface of the nanoparticles and these changes affect biodistribution, efficacy, and toxicity of the nanoparticles.


2018 ◽  
Vol 7 (1) ◽  
pp. 1-20 ◽  
Author(s):  
Aleksandra Osika ◽  
Małgorzata Wistuba ◽  
Ireneusz Malik

Abstract The aim of the study is to reconstruct the development of landslide relief in the Kamienne Mountains (Central Sudetes, SW Poland) based on a DEM from LiDAR data. Analyses of relief and geological maps in ArcGIS 10.5 and of slope cross-sections in Surfer 14 allowed to distinguish different types of landslide relief, developed in latites and trachybasalts lying above claystones and mudstones. The types vary from small, poorly visible landslides to vast landslides with complex relief. They were interpreted as consecutive stages of geomorphic evolution of hillslope-valley topography of the study area. Two main schemes have been established which explain the development of landslide slopes in the Kamienne Mts: (1) upslope, from the base of the slope towards the mountain ridge and (2) downslope, beginning on the top of the mountain ridge. The direction of landslide development depends on the thickness of volcanic rocks in relation to underlying sedimentary rocks. When the latter appear only in the lowest part of the slope, landslides develop upslope. If sedimentary rocks dominate on the slope and volcanic rocks form only its uppermost part, landslides develop downslope. The results show that landsliding leads to significant modifications of relief of the study area, including complete degradation of mountain ridges.


2017 ◽  
Vol 53 ◽  
pp. 269-284
Author(s):  
Martin A. Becker ◽  
Rebecca B. Chamberlain ◽  
Harry M. Maisch ◽  
Alex Bartholomew ◽  
John A. Chamberlain

Glacial erratics belonging to the Rickard Hill facies (RHF) of the Saugerties Member of the Schoharie Formation (upper Emsian: Lower Devonian) occur scattered throughout the Piedmont of northern New Jersey and Lower Hudson Valley of New York. These RHF glacial erratics contain an assemblage of trilobites belonging to: Anchiopella anchiops, Burtonops cristatus, Calymene platys, Terataspis grandis, cf. Trypaulites sp. and cf. Coniproetus sp. This RHF glacial erratic trilobite assemblage consists predominately of disarticulated cephala and pygidia that were originally preserved as part of a localized, third-order eustatic sea level lag deposit in the Helderberg Mountains region of central New York State and subsequently transported in glacially plucked blocks by the Hudson-Champlain Lobe of the Laurentide Ice Sheet southward into New Jersey. Physical and chemical weathering during glacial erosion, transportation and deposition of the RHF glacial erratics has revealed some anatomical features of these trilobites in high detail along with other invertebrates. This unique sequence of weathering reveals additional characteristics that bear upon issues of bathymetric controls on upper Schoharie Formation lithology, trilobite faunal abundance and taphonomy during the upper Emsian (Lower Devonian) of eastern New York State.  


2020 ◽  
Vol 118 (2) ◽  
pp. e2007051117
Author(s):  
Eric C. Dunham ◽  
John E. Dore ◽  
Mark L. Skidmore ◽  
Eric E. Roden ◽  
Eric S. Boyd

Life in environments devoid of photosynthesis, such as on early Earth or in contemporary dark subsurface ecosystems, is supported by chemical energy. How, when, and where chemical nutrients released from the geosphere fuel chemosynthetic biospheres is fundamental to understanding the distribution and diversity of life, both today and in the geologic past. Hydrogen (H2) is a potent reductant that can be generated when water interacts with reactive components of mineral surfaces such as silicate radicals and ferrous iron. Such reactive mineral surfaces are continually generated by physical comminution of bedrock by glaciers. Here, we show that dissolved H2 concentrations in meltwaters from an iron and silicate mineral-rich basaltic glacial catchment were an order of magnitude higher than those from a carbonate-dominated catchment. Consistent with higher H2 abundance, sediment microbial communities from the basaltic catchment exhibited significantly shorter lag times and faster rates of net H2 oxidation and dark carbon dioxide (CO2) fixation than those from the carbonate catchment, indicating adaptation to use H2 as a reductant in basaltic catchments. An enrichment culture of basaltic sediments provided with H2, CO2, and ferric iron produced a chemolithoautotrophic population related to Rhodoferax ferrireducens with a metabolism previously thought to be restricted to (hyper)thermophiles and acidophiles. These findings point to the importance of physical and chemical weathering processes in generating nutrients that support chemosynthetic primary production. Furthermore, they show that differences in bedrock mineral composition can influence the supplies of nutrients like H2 and, in turn, the diversity, abundance, and activity of microbial inhabitants.


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