scholarly journals Geochemical Behavior of Different Chemical Elements during Weathering of the Basalts in Changbai Mountain, Northeast China

2021 ◽  
Vol 13 (22) ◽  
pp. 12796
Author(s):  
Tian Lan ◽  
Libo Hao ◽  
Jilong Lu ◽  
Yechang Yin ◽  
Xiaoqing Chen ◽  
...  

Rock weathering is the main source of element geochemical cycle, which has a very important impact on the environment. Three well-developed basalt weathering profiles in Changbai Mountain area are selected in this study, and the samples of parent rock, parent material layer, sedimentary layer, and leaching layer are systematically collected. The systematic study showed that the basalt in the study area experienced moderate chemical weathering under warm and humid climate conditions, with leaching of some major elements such as silicon and aluminum. The distribution of the rare earth elements (REE) in the weathering products recalls that of an alkali-basalt, with an evident fractionation between light- and heavy-REE. Such a feature is therefore referable to the parent volcanic rock, although with some degree of leaching.

2011 ◽  
Vol 30 (1) ◽  
pp. 95-103 ◽  
Author(s):  
Łukasz Stachnik ◽  
Łukasz Uzarowicz

The Relationship between Dissolved Solids Yield and the Presence of Snow cover in the Periglacial Basin of the Obruchev Glacier (Polar Urals) during the Ablation SeasonHydrochemical investigations were carried out in the periglacial basin of Obruchev Glacier (Polar Urals, Russia) in order to provide a quantitative and qualitative comparison of dissolved solids yields during the ablation season with and without snow cover taking into account the mineral composition of rocks and deposits occurring in the studied area. The concentration of dissolved solids in the waters of the investigated basin is very low (about 7.0-8.9 μS cm-1). It is most of all due to harsh local climate conditions as well as the presence of minerals resistant to weathering in the parent material. Both factors contribute to the low rate of chemical weathering in the area. Results obtained indicate that a larger dissolved solids yield was transported during the period with snow cover (106 kg km-2day-1, on average), than at the same time of the year but without snow cover (13 kg km-2day-1, on average) indicating that melting snow is an important factor influencing the yield of dissolved solids in surface waters.


Minerals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 678 ◽  
Author(s):  
Sun ◽  
Wang ◽  
Guo ◽  
Wang ◽  
Jiang ◽  
...  

We performed mineralogical and geochemical analyses of core samples from the Lenghuqi area in the northern marginal tectonic belt of the Qaidam Basin. The clay mineralogy of the Xiaganchaigou Formation sandstone is dominated by I + I/S + C types and characterized by high illite, a higher mixed-layer illite/smectite and chlorite, lesser smectite, and an absence of kaolinite. The clay minerals reflect that the Oligocene sedimentary basin formed in an arid-semi-arid climate with weak leaching and chemical weathering, and that diagenesis occurred in a K+- and Mg2+-rich alkaline environment. Measured major oxide concentrations show clear correlations. The lower Xiaganchaigou Formation is representative of a dry and cold freshwater sedimentary environment, whereas the upper Xiaganchaigou Formation is warmer and more humid. Trace element and rare earth element variations indicate that the paleoclimate conditions of the lower Xiaganchaigou Formation sedimentary period were relatively cold and dry, while the upper Xiaganchaigou Formation formed under warmer and more humid climate conditions. These findings reflect a global climate of a cold and dry period from the late Eocene to early Oligocene, and a short warming period in the late Oligocene.


2012 ◽  
Vol 33 (1) ◽  
pp. 41-62 ◽  
Author(s):  
Anna Mozer

Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica New evidence of Eocene preglacial environments has been found on the southern coast of Ezcurra Inlet on King George Island, South Shetland Islands, West Antarctica. Plant remains (trunks, leaves, detritus) and carbonaceous seams and beds occur in sedimentary strata in a 4 km long Cytadela outcrop of the Point Thomas Formation. They are an evidence for the presence and diversity of terrestrial vegetation in the northern Antarctic Peninsula region. The forests were composed mostly of Podocarpaceae-Araucaria-Nothofagus, with an undergrowth of hygrophilous and thermophilous ferns, and grew on volcanic slopes and surrounding lowland areas of King George Island during breaks in volcanic activity. The succession that crops out at Cytadela provides a record of changing climatic conditions from a warm and wet climate with extensive vegetation to a much drier climate with limited vegetation and ubiquitous weathering of volcanic bedrock. The geochemical indices of weathering (CIA, PIA and CIW) have narrow and relatively high value ranges (76-88), suggesting moderate to high chemical weathering under warm and humid climate conditions. The decrease in humidity and the decline in plant life through the succession can be related to the gradually cooling climate preceding development of the Oligocene ice cover across the Antarctic continent.


1987 ◽  
Vol 19 (10) ◽  
pp. 1-10 ◽  
Author(s):  
K. Bucksteeg

Waste water treatment in helophyte beds under humid climate conditions has been favoured by some German ecologists for some years. The idea is to cause waste water to flow horizontally through the root zone of helophytes to achieve satisfactory effluent properties. There exist many highly different proposals regarding the choice of soil and helophytes to be applied, bed area, design of inlets and outlets and operation conditions. A few plants have been operated in practice for some years. It appears that clogging is one of the main problems occurring in these plants. The hydraulic uptake capacity of soil is discussed in Darcy's law. Comparisons with observations of plants in operation are drawn. The interactions between soil properties, its uptake capacity, BOD5-, COD-, N- and P-reduction are evaluated. The effluent results of helophyte beds are compared with those of low-loaded trickling filters and of ponds used for sewage treatment in small villages in rural areas of Germany. It has been proved that the total construction costs of sewage treatment plants with helophyte beds used as the biological stage are higher when compared with those of conventional plants in general.


2020 ◽  
Vol 4 (1) ◽  
pp. 18
Author(s):  
Richard Viskup ◽  
Yana Vereshchaga ◽  
Anna Theresia Stadler ◽  
Theresa Roland ◽  
Christoph Wolf ◽  
...  

Pollutant emissions from vehicles form major sources of metallic nanoparticles entering the environment and surrounding atmosphere. In this research, we spectrochemically analyse the chemical composition of particle matter emissions from in-use diesel engine passenger vehicles. We extracted diesel particulate matter from the end part of the tail pipes of more than 70 different vehicles. In the laboratory, we used the high-resolution laser-induced breakdown spectroscopy (LIBS) spectrochemical analytical technique to sensitively analyse chemical elements in different DPM samples. We found that PM is composed of major, minor and trace chemical elements. The major compound in PM is not strictly carbon but also other adsorbed metallic nanoparticles such as iron, chromium, magnesium, zinc and calcium. Besides the major elements in DPM, there are also minor elements: silicon, nickel, titan, potassium, strontium, molybdenum and others. Additionally, in DPM are adsorbed atomic trace elements like barium, boron, cobalt, copper, phosphorus, manganese and platinum. All these chemical elements form the significant atomic composition of real PM from in-use diesel engine vehicles.


Cerâmica ◽  
2008 ◽  
Vol 54 (331) ◽  
pp. 356-360 ◽  
Author(s):  
A. Blandine ◽  
G. Bernard ◽  
B. Essaïd

Cement is a ubiquitous material that may suffer hazardous weathering. The chemical weathering of cement in natural environment is mostly characterized by the leaching of CaO and the addition of CO2. The different weathering zones that develop at the expense of the cement may be predicted by the help of chemical potential phase diagrams; these diagrams simulate the behaviour of systems open to some chemical elements. Some components have a so-called inert status, that is to say the system is closed for these components, their amount in the system remains constant; some other components have a mobile status, that is to say these components can be exchanged with the outside of the system, their amount can vary from one sample zone to another. The mobile components are represented in the model by their chemical potentials (linked to their concentrations) that are variable in the external environment. The main features of the weathering of a cement system open to CaO and CO2 are predicted in a phase diagram with µCaO et µCO2 as diagram axes. From core to rim, one observes the disappearance of portlandite, ettringite and calcium monosulfoaluminate, the precipitation of calcite and amorphous silica, the modification of the composition of the CSH minerals (hydrated calcium silicates) that see a decrease of their c/s ratio (CaO/SiO2) from the core to the rim of the sample. For the CSH minerals, we have separated their continuous solid solution into three compositions defined by different CaO/SiO2 ratios and called phases 1, 2 and 3: CaO = 0.8, 1.1, 1.8 respectively for one mole of SiO2 knowing that H2O varies in the three compositions.


2015 ◽  
Vol 101 (5) ◽  
pp. 514-519 ◽  
Author(s):  
Wei Fang ◽  
Lisi Yao ◽  
Xiaomei Cao ◽  
Yi Sun ◽  
Xiaolong Zhang ◽  
...  

2018 ◽  
Vol 36 (4) ◽  
pp. 910-941
Author(s):  
Jian Song ◽  
Zhidong Bao ◽  
Xingmin Zhao ◽  
Yinshan Gao ◽  
Xinmin Song ◽  
...  

Studies have found that the Permian is another important stratum for petroleum exploration except the Jurassic coal measures within Turpan–Hami Basin recently. However, the knowledge of the depositional environments and its petroleum geological significances during the Middle–Late Permian is still limited. Based on the analysis about the sedimentological features of the outcrop and the geochemical characteristics of mudstones from the Middle Permian Taerlang Formation and Upper Permian Quanzijie Formation in the Taoshuyuanzi profile, northwest Turpan–Hami Basin, this paper makes a detailed discussion on the Middle–Late Permian paleoenvironment and its petroleum geological significances. The Middle–Upper Permian delta–lacustrine depositional system was characterized by complex vertical lithofacies assemblages, which were primarily influenced by tectonism and frequent lake-level variations in this area. The Taerlang Formation showed a significant lake transgression trend, whereas the regressive trend of the Quanzijie Formation was relatively weaker. The provenance of Taerlang and Quanzijie Formations was derived from the rift shoulder (Bogda Mountain area now) to the north and might be composed of a mixture of andesite and felsic volcanic source rocks. The Lower Taerlang Formation was deposited in a relatively hot–dry climate, whereas the Upper Taerlang and Quanzijie Formations were deposited in a relatively humid climate. During the Middle–Late Permian, this area belonged to an overall semi-saline water depositional environment. The paleosalinity values showed stepwise decreases from the Lower Taerlang Formation to the Upper Quanzijie Formation, which was influenced by the changes of paleoclimate in this region. During the Middle–Late Permian, the study area was in an overall anoxic depositional environment. The paleoenvironment with humid climate, lower paleosalinity, anoxic condition, and semi-deep to deep water during the deposition of the Upper Taerlang Formation was suitable for the accumulation of mudstones with higher TOC values.


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