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Tytuł:
Palaeoecology of the Holsteinian lake in vicinity of Wilczyn (eastern Poland) based on molluscan studies
Autorzy:
Szymanek, M.
Powiązania:
https://bibliotekanauki.pl/articles/2060329.pdf
Data publikacji:
2013
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
palaeoecology
molluscs
Holsteinian
lacustrine sediments
Opis:
Malacological studies of two profiles of the Holsteinian (Mazovian) Interglacial from eastern Poland – Roskosz and Wilczyn 1/12 – are presented. They are connected with the northern part of the Wilczyn palaeolake and seems to document palaeoecological changes in the part of the climatic optimum and the post-optimal period. Mollusc communities are typical of lake environs. The latter is supported by biometry of Pisidium moitessierianum. Higher energy conditions are evidenced by rheophile species P. henslowanum and P. nitidum in the lowermost part of the Roskosz section. Mollusc assemblages with Lithoglyphus jahni, with Valvata piscinalis and Bithynia tentaculata as well as with Valvata piscinalis are distinguished at Roskosz. They record changes in aquatic vegetation and depth conditions. Malacofauna from Wilczyn 1/12 is dominated by V. piscinalis, V. piscinalis f. antiqua and B. tentaculata. Limited contribution of temperate gastropods Viviparus diluvianus and L. jahni as well as the occurrence of some cold-loving forms indicate a deterioration of thermal conditions. Shallow-water habitats and expansion of reed zones are inferred from proportions of Bithynia shells and opercula.
Źródło:
Geological Quarterly; 2013, 57, 4; 637--648
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of litho- and pedogenic processes on Luvisols formation of selected area of Vistula Glaciation
Autorzy:
Jaworska, H.
Dąbkowska-Naskręt, H.
Kobierski, M.
Powiązania:
https://bibliotekanauki.pl/articles/2060473.pdf
Data publikacji:
2014
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
luvisols
lithological discontinuity
lessivage
glacial sediments
Opis:
The objective of the study was to determine the effect of litho- and pedogenic processes on soils of the selected area of Vistula Glaciation, based on profile distribution of unweathered components such as titanium, zirconium and silica in relation to their morphology, mineralogy, micromorphology and physicochemical properties. The predominant type of soilin the study area are Luvisols. Analysis of texture allowed to classify the investigated soils to sandy silts with loamy material as their subsoil. In the bulk soil silica dominates and its content was in the range 71.4 to 88.6%. The content of TiO2 within the profiles is fairy similar, without clear patterns in the profile distribution. The total content of zirconium in the samples was in range of 95.13 to 212.15 mg x kg-1. In the profile distribution of zirconium higher content of Zr was observed in the upper horizons compared to the top layerin all of theanalysed profiles, indicating different origin of soil material. Statistical analysis showed positive correla- tion between the total content of zirconium and the content of fraction 0 0.05-0.002 mm (correlation coefficient value: 0.692384; significance level - p < 0.05) and negative correlation between zirconium and clay content (correlation coefficient: -0.668157; p < 0.05). The lithologic discontinu i ty within profiles of the investigated soils has been additionally has proved by X-ray analysis of the clay fraction. The micromorphological analysis confirmed the complex genesis of the studied soils. The results of the study clearly showed an overall inhomogeneity and stratification of the soils. Studied Luvisols did not form as weath- ering product of homogeneous bedrock. Changes in granulometric and chemlcal composition within soil profiles are the consequence of translocation of clay fraction during lessivage as well as lithologic discontinul ty of the solum.
Źródło:
Geological Quarterly; 2014, 58, 4; 685--694
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The facies and biota of the oldest exposed strata of the Eocene La Meseta Formation (Seymour Island, Antarctica)
Autorzy:
Tatur, A. E.
Krajewski, K. P.
lvalle de, R. A.
Powiązania:
https://bibliotekanauki.pl/articles/2058745.pdf
Data publikacji:
2011
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Antarctica
Seymour
Eocene
sediments
goethite
thanatocoenosis
Opis:
La Meseta Formation is made up of estuarine and shallow marine, fossiliferous clastic deposits 720 m thick that provides a unique record of marine and terrestrial biota of Antarctic ecosystems preceding continental glaciation in the Oligocene. The lower limit of this formation has been poorly known, and therefore it has been carefully investigated. The lowest part of the La Meseta Formation, at the southern bank of a palaeodelta, is represented by relics of a prograding sequence of sediments deposited in the wave-dominated part of a deltaic system in the offshore and lower and upper shoreface environments. The sequence is completed landwards by younger tidal plain sediments deposited at 40 m lower altitude in a relatively protected, central estuarine basin, which was dominated by tidal activity and influenced by periodic fluvial inflow. These strata were deposited during a late Paleocene or Ypresian/Lutetian lowstand of sea level, which might reflect a glaciation event or glacioisostatic rebound of land following deglaciation of hypothetic Antarctic inland glaciers. Forced regression of sea level and seaward expansion of a deltaic freshwater environment, led to local extinction of a unique assemblage of marine echinoderms, bryozoans, corals and brachiopods. These marine fossils, representing a thanatocoenosis, are perfectly preserved due to syngenetic goethite permineralisation. This process owed its origin to excess reactive iron coming from sulphide-rich bedrock through weathering processes and acid sulphate drainage of the neighbouring land area.
Źródło:
Geological Quarterly; 2011, 55, 4; 345-360
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The development of unconsolidated sedimentary coastal cliffs (Pobrzeże Kaszubskie, Northern Poland)
Autorzy:
Uścinowicz, G.
Jurys, L.
Szarafin, T.
Powiązania:
https://bibliotekanauki.pl/articles/2060378.pdf
Data publikacji:
2017
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
cliff coast
landslides
soft sediments
Southern Baltic
Opis:
In the course of fieldwork based on geological and landslide mapping and spatial analyses of map information at least 2 types of landslides were identified. Type I: simple landslides developed in homogeneous and undisturbed rocks, for instance – loams, clays and sands. This type of landslide includes many examples developed mainly on the stretch (segment of the studied area) approximately between 132.25 and 133.50 km and 128.50 and 129.50 km of the Polish coastline. Type II: complex landslides in which the movement and displacement of rock masses occurs under complex geological and hydrogeological conditions. The complex factors are determined by phenomena such as glaciotectonics, discontinuities of rock layers and thrust zones; the slip surface occurs at considerable depths, and sometimes several slip surfaces can be distinguished. These landslide types are located in the vicinity of Jastrzębia Góra and Rozewie, near km 134 and 131.5. Prediction of the formation of this landslide types is difficult. Even if long-term observations are available, the mass movement, variable over time, is difficult to interpret. It is clear that the changes are continuous, but occur with varying intensity. Proper recognition of the types of mass movement is crucial to establishing the appropriate methods to prevent their development.
Źródło:
Geological Quarterly; 2017, 61, 2; 491--501
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chemical composition of soil and lake sediments - an indicator of geological processes in Lithuania
Autorzy:
Gregorauskiene, V.
Kadunas, V.
Powiązania:
https://bibliotekanauki.pl/articles/2059444.pdf
Data publikacji:
2000
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Lithuania
trace elements
soil
lake sediments
geoindicators
Opis:
Long-term multipurpose geochemical studies in Lithuania show that the chemical composition of surface sediment can be used as an indicator of geological process: duration of weathering, soil formation and thickness of sediment. The chemical composition of upper and lower soil layers and of lake sediments gives information on past sedimentation: the type and age of Quaternary deposits and the location and depth of Pleistocene glaciolacustrine basins. We therefore have a baseline to predict changes in surface chemistry provoked by current anthropogenic pressures.
Źródło:
Geological Quarterly; 2000, 44, 4; 347-354
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dumpstones as records of overturning ice rafts in a Weichselian proglacial lake (Rügen Island, NE Germany)
Autorzy:
Pisarska-Jamroży, M.
Van-Loon, A. J. T.
Bronikowska, M.
Powiązania:
https://bibliotekanauki.pl/articles/2060089.pdf
Data publikacji:
2018
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
dumpstones
dropstones
ice-rafted debris
Weichselian
glaciolacustrine sediments
Opis:
Dumpstones and dropstones up to 0.8 m in size occur in a silty/sandy Weichselian glaciolacustrine succession near Dwasieden on Rügen Island in the SW Baltic Sea (NE Germany). The deposits are exceptional because two levels of dumpstones and dropstones are present, suggesting two dumping phases interrupting characteristic fine-grained glaciolacustrine sedimentation. Plastic downwarping of sediments below the dumpstones and dropstones result in soft-sediment deformation structures. The distribution and orientation of the long axes of the clasts are useful tools for the reconstruction of the state of the lake bottom, as well as for the water depth. The horizontal position of the gravels and boulders (parallel to the bedding) suggests deposition in relatively shallow-water. The dumping events are linked to iceberg rafting in a glacial lake during the Weichselian Glaciation (MIS 2).
Źródło:
Geological Quarterly; 2018, 62, 4; 917-924
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New evidences of Holocene tectonic and volcanic activity of the western part of Lake Sevan (Armenia)
Autorzy:
Avagyan, Ara
Sahakyan, Lilit
Meliksetian, Khachatur
Karakhanyan, Arkadi
Lavrushin, Vasily
Atalyan, Tatul
Hovakimyan, Hayk
Avagyan, Seda
Tozalakyan, Petros
Shalaeva, Evgenia
Chatainger, Christine
Sokolov, Sergey
Sahakov, Arkadi
Alaverdyan, Gagik
Powiązania:
https://bibliotekanauki.pl/articles/2059674.pdf
Data publikacji:
2020
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
active fault
gas emission
lake sediments
palaeomagnetism
lake tsunami
Opis:
The purpose of this paper is to present new data on active geological processes in the Lake Sevan Basin and to show its multidisciplinary aspects. The investigations of its structures, recent lake sediments, and lake floor gas emission allow a better understanding of the history of geological development and the recent tectonic and volcanic activity of the basin. This paper summarizes underwater investigations of active geological features of Lake Sevan, undertaken for the first time in Armenia. More than 30 aligned underwater-source related gas emission points were discovered. The gas contains carbon dioxide of volcanic or volcanogenic-metamorphogenic origin and can be related to unloading of deep fluid systems. This allows defining the Noratus-Kanagegh Fault segment trace below the recent Lake Sevan floor sediments. The discovery of the subaqueous segment of active fault shows the presence of another natural hazard of lake tsunami related to possible future co-seismic rupture. The recent sediments of the northwestern Lake Sevan coastline are sandwiched between two blocky lava flows. The radiocarbon dating of bones of bovine mammals (with entire skull), found ~15 cm from the cover of the lake sediments, suggests that the upper blocky basaltic-andesite layer can be a result of eruption younger than ~3400 years BP. About 80 m of the Noratus sequence sediments have been sampled for palaeomagnetic study and the age of 3.1-2.3 Ma for the lower part (42 m) is obtained. The upper and post-Gelasian activity of the Noratus-Kanagegh Fault is proven by a cross-cutscoria layer of 2.30 ±0.15 Ma K/Ar age.
Źródło:
Geological Quarterly; 2020, 64, 2; 288--303
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new Eemian Interglacial to Early Vistulian site at Łanięta, central Poland
Autorzy:
Balwierz, Z.
Roman, M.
Powiązania:
https://bibliotekanauki.pl/articles/2059929.pdf
Data publikacji:
2002
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Central Poland
Eemian Interglacial
Early Vistulian
lake sediments
palynostratigraphy
Opis:
The Łanięta site with fossil lake deposits is situated just in front of the maximum extent of Vistulian Glaciation ice. Palynological analysis shows that lake accumulation lasted through the Eemian Interglacial and almost the whole Early Vistulian, the longest record of this time interval in this part of Poland. Two warm interstadial-rank oscillations (Brörup and Odderade) and two stadials have been distinguished during the Early Vistulian. The older of these is correlated with the Herning Stadial while younger one equates with the Rederstal Stadial of the German succession.
Źródło:
Geological Quarterly; 2002, 46, 2; 207-218
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ageing of organic matter in incubated freshwater sediments; in fer ences from C and H isotope ratios of methane
Autorzy:
Szynkiewicz, A.
Modelska, A.
Jedrysek, M-O.
Kurasiewicz, M.
Mastalerz, M.
Powiązania:
https://bibliotekanauki.pl/articles/2059090.pdf
Data publikacji:
2008
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
methanogenic pathways
carbon and hydrogen isotopes
incubation
freshwater sediments
Opis:
The freshwater sediments were incubated under anaerobic conditions for 570 and 879 days to in vestigate the potential variations in methanogenic pathways due to increasing sediment age and recalcitrance of organic matter. The methanogenic pathways did not shift from acetate fermentation toward CO2 reduction, as indicated by the observed variations of the isotopic composition of methane in natural conditions. It appeared, however, that the observed decrease of methane concentration (from 86 to 39%) and continuous in crease in d13C(CH4) (from –69.7 to –59.0‰) and dD(CH4) values (from –381 to –320‰) resulted mainly from exhaustion of at least one methanogenic substratein the incubated sediments. To better understand processes controlling the variations of delta exp.13C(CH4) and deltaD(CH4) values relative to ageing of organic matter, the method of principal component analysis (PCA) was used. This method offers good comparison of the relation ships between variables when a larger number of parameters control a given process in the same time period. In this study, the PCA indicated three distinctive factors that controlled decomposition of organic matter during the incubation. Factor 1 explained 33% of observed variations among the variables and had positive (0.93–0.92) loadings for electric conductivity and DIC concentration and negative loading for delta exp.13C(CH4) val ues (–0.72). Factor 2 accounted for 28% and had high posi ive loading for deltaD(CH4) value (0.86) and high negative loading for methane concentration (–0.81). Factor 3 accounted for 19% and exhibited high positive loadings for temperature (0.90) and delta exp.13C(DIC) value (0.69). Factors 1 and 2 were directly linked to the methanogenesis and indicated that bigger accumulation of bio-products in sediments is likely important for variations of delta exp.3C and deltaD of methane. This study shows that method of principal component analysis might be a useful tool while studying biogeochemical carboncy cleduring early digenesis of freshwater sediments.
Źródło:
Geological Quarterly; 2008, 52, 4; 383-383
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New approach to garnet redistribution during aeolian transport
Autorzy:
Lisá, L.
Buriánek, D.
Uher, P.
Powiązania:
https://bibliotekanauki.pl/articles/2059212.pdf
Data publikacji:
2009
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Weichselian
Pleistocene
Czech Republic
aeolian sediments
garnet composition
provenance
Opis:
Garnet composition within Late Pleistocene (Weichselian) loess and loess-like deposits was studied in 13 samples of sediment heavy mineral fractions from Moravia and Silesia (Czech Republic). Four areas differing in garnet chemistry were identified, and some regional trends in garnet composition changes were documented. The data obtained support the generally accepted conclu ion of prevailing westerly winds during Weichselian loess deposition. Metamorphic rocks of the Bohemian Massif together with contributions fromig neous (mainly granitic) and sedimentary rocks were indicated as a source for the Weichselian loess and loess-like deposits studied. Local differences in garnet composition depend on the basement source rocks, on prevailing wind direction, on regional geomorphology and on transport distance.
Źródło:
Geological Quarterly; 2009, 53, 3; 333-340
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Dobrotiv Formation (Miocene) in the Boryslav-Pokuttya and Sambir nappes of the Ukrainian Carpathians : a record of sedimentary environmental change in the development of the Carpathian Foredeep Basin
Autorzy:
Oszczypko, N.
Uchman, A.
Bubniak, I.
Powiązania:
https://bibliotekanauki.pl/articles/2060063.pdf
Data publikacji:
2014
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
non-marine
deltaic sediments
molasse
mammal and bird footprints
Opis:
The late Early Miocene Dobrotiv Formation, a 700–800-m-thick unit, was deposited in a subsiding platform margin, which become involved in the marginal part of the Outer Eastern Carpathian accretionary wedge. The sedimentary succession from the Sloboda Conglomerate up to the Dobrotiv Formation records a transition from alluvial fan through fan-delta to deltaic deposits, followed by the fluvial plain-channel facies of the Stebnyk Formation. The deltaic deposits are mud-dominated, with poorly developed thickening-up packets of beds. Efficient sediment accumulation was balanced by subsidence caused by subsurface loading. Emerged parts of the deltaic sedimentary system include tetrapod footprints and raindrop imprints. The general absence of mudcracks in the Dobrotiv Formation suggests a humid climate. Deposits of the Sloboda, Dobrotiv and Stebnyk formations form fining- and thinning-upwards clastic wedge successions along the Ukrainian Carpathians.
Źródło:
Geological Quarterly; 2014, 58, 3; 393--408
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Depth of the water column in relation to carbon isotope ratios in methane in fresh water sediments
Autorzy:
Jędrysek, M. O.
Powiązania:
https://bibliotekanauki.pl/articles/2058951.pdf
Data publikacji:
2005
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
stable carbon isotopes
methane
fresh water sediments
diagenesis
environmental record
Opis:
Methane was collected from the surficial sedimentary layer (0 to about 20 cm) in 45 fresh water lakes in Poland. Sampling was also carried out at various depths of the over lying water column (0.15 to 12 m) between noon and early after noon, on a seasonal basis, between 1992 and 1996. A positive correlation between the depth of the lake water, the δ13 C (CH4) value (from ca. -l.4 to -2.3% per l m depth) and the wider δ13 C (CH4) variation over the thermocline are probably due to: the time of sinking of organic particles resulting in more in tense acetate fermentation in shallower portions of the lake; the temperature variation; differences in the precursors of methane, the diffusion effect, and an increase of bioavailable DIC (dissolved inorganic carbon) at greater depths. Non-seasonal variation of isotope ratios in methane and the depth-isotope ratio correlation show that the lake system is in dynamic equilibrium on a scale of hours and days. Therefore, earlier models of methanogenesis relating and the atmospheric methane isotopic budget, proposed by other authors and based on sampling of methane from sediments, need to be revised. More over, δ13 C (CH4) values higher during seasonal over turn (mixing of benthic and surface waters) than during stagnation, have been observed. This is probably due to the fact that during over turn periods some organic compounds (methane precursors) and methane in the surficial part of sediments, are oxidized with a resalting kinetic isotope effect. It is proposed that oxidation of methane and other organic compounds during seasonal over turn may be responsible for post-depositional lamination observed as pale (autumn over turn) and dark (summer organic-rich unoxic stagnation) millimetres-thick layers in fresh water lake sediments.
Źródło:
Geological Quarterly; 2005, 49, 2; 151-164
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lithology and diagenesis of the poorly consolidated Cambrian siliciclastic sediments in the northern Baltic Sedimentary Basin
Autorzy:
Raidla, V.
Kirsimäe, K.
Bityukova, L.
Joeleht, A.
Shogenova, A.
Šliaupa, S.
Powiązania:
https://bibliotekanauki.pl/articles/2059134.pdf
Data publikacji:
2006
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Cambrian
Baltic Sedimentary Basin
siliclastic sediments
diagenesis
clay minerals
compaction
Opis:
The present study discusses lithology and diagenetic characteristics of the siliciclastic Cambrian and the enclosing Ediacaran and Ordovician deposits in the northern Baltic Sedimentary Basin (BSB). The Neoproterozoic and Lower Palaeozoic sediments are despite their age unconsolidated with primary porosity of 20-25% for both shales and sandstones. The sparse Fe-dolomite cementation of arenitic and subarenitic sandstones and siltstones occurs mainly at lithological contacts with the massive Ediacaran and Lower Cambrian claystones and is probably related to ions released during llitization. In contrast to weak mechanical and chemical compaction of sandstone, the clay mineral diagenesis of Cambrian deposits is well advanced. The highly illitic (80-90%) nature of illite-smectite (I-S) suggests evolved diagenetic grade of sediments which conflicts with shallow maximum burial and low compaction. Smectite-to-illite transformation has resulted in formation of diagenetic Fe-rich chlorite in claystones. Some porosity reduction of sandstones is due to formation of authigenic kaolinite at the expense of detrital mica or K-feldspar.
Źródło:
Geological Quarterly; 2006, 50, 4; 395-406
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Clay minerals in cave sediments and terra rossa soils in the Montagnola Senese karst massif (Italy)
Autorzy:
Iacoviello, F.
Martini, I.
Powiązania:
https://bibliotekanauki.pl/articles/2060561.pdf
Data publikacji:
2013
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
cave sediments
terra rossa
clay minerals
red mud
Montagnola Senese
Opis:
Reddish mud-rich sediments are common in several karst areas, in the form of red surface soils and clastic cave infilling. The origin and significance of red surface soils have been largely debated over the last years, whilst clastic mud-rich sediments in cave environments have received less attention by geoscientists. The genetic relation between these two materials still remains uncertain. In fact, these sediments are mainly constituted by fine materials, therefore, their study has been generally focused on the clay fraction only.This paper compares the clay fraction of red surface soils and mud-rich cave sediments in the Montagnola Senese massif. Previous studies have demonstrated that in this area red cave muds originate from the erosion of the red surface soils and their consequent re-deposition in the cave environment. Despite these well-established genetic relations, notable differences in the clay fraction of these two materials have been recognized in the present study. These differences are likely to be attributable to the different grades of pedogenetic alteration that affected the two materials. This study demonstrates that the genetic relations between mud-rich cave sediments and red surface soils can be misinterpreted when the clay mineral fraction only is considered.
Źródło:
Geological Quarterly; 2013, 57, 3; 527--536
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Geochemistry of surface sediments from the northwestern Gulf of Mexico : implications for provenance and heavy metal contamination
Autorzy:
Armstrong-Altrin, John S.
Botello, Alfonso V.
Villanueva, Susana F.
Soto, Luis A.
Powiązania:
https://bibliotekanauki.pl/articles/2058576.pdf
Data publikacji:
2019
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Tamaulipas
deep-sea sediments
enrichment factor
contamination
principle component analysis
Opis:
Thirty-five near-surface sediment samples were recovered from the continental shelf and upper slope regions of the north-western (NW) Gulf of Mexico. The geochemical data of the sediments recovered were examined to investigate the weathering intensity, provenance, palaeo-oxygenation condition, and level of heavy metal contamination. The sediments analysed showed a moderate to high intensity of chemical weathering. Major and trace element concentrations indicated a terrigenous origin, closely related to the weathering of rocks rich in aluminosilicates. The results of this study further revealed that major rivers, the Bravo and Soto La Marina, played an important role in delivering sediments to the study area. The concentration of transition trace elements such as Cr, Cu, Ni, and V revealed that the sediments were derived from intermediate rocks such as andesite. The V/Cr, Ni/Co, and Cu/Zn ratios in the sediments were <2, <5, and <1, respectively, suggesting a depositional process occurred under well-oxygenated conditions. Principle Component Analysis (PCA) did not show a significant difference in sediment texture between the continental shelf and slope areas. The enrichment factor (EF) and Geo-accumulation index (lgeo) values were <2 and <1, respectively, suggesting the absence of an anthropogenic input.
Źródło:
Geological Quarterly; 2019, 63, 3; 522--538
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł

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