Influence of volcanic activity and anthropic impact in the trace element contents of fishes from the North Patagonia in a global context

2015 ◽  
Vol 187 (11) ◽  
Author(s):  
D. F. Bubach ◽  
P. J. Macchi ◽  
S. Pérez Catán
Keyword(s):  
Trace Element ◽  
Volcanic Activity ◽  
Anthropic Impact ◽  
Global Context ◽  
North Patagonia ◽  
The North ◽  
Trace Element Contents ◽  
Element Contents

scholarly journals Evolution of Subduction Dynamics beneath West Avalonia in Middle to Late Ordovician Times

Lithosphere ◽  
2020 ◽  
Vol 2020 (1) ◽  
pp. 1-22
Author(s):  
Pierre Jutras ◽  
J. Brendan Murphy ◽  
Dennis Quick ◽  
Jaroslav Dostal
Keyword(s):  
Trace Element ◽  
Partial Melting ◽  
Volcanic Rocks ◽  
Upper Ordovician ◽  
The North ◽  
Trace Element Contents ◽  
Element Contents ◽  
Arc Setting ◽  
Back Arc ◽  
High Degree

Abstract Middle to Upper Ordovician volcanic rocks in the Arisaig area of Nova Scotia, Canada, constitute the only known record of volcanism in West Avalonia during that interval. Hence, they have been extensively studied to test paleocontinental reconstructions that consistently show Avalonia as a drifting microcontinent during that period. Identification of volcanic rocks with an intermediate composition (the new Seaspray Cove Formation) between upper Darriwilian bimodal volcanic rocks of the Dunn Point Formation and Sandbian felsic pyroclastic rocks of the McGillivray Brook Formation has led to a reevaluation of magmatic relationships in the Ordovician volcanic suite at Arisaig. Although part of the same volcanic construction, the three formations are separated by significant time-gaps and are shown to belong to three distinct magmatic subsystems. The tectonostratigraphic context and trace element contents of the Dunn Point Formation basalts suggest that they were produced by the high-degree partial melting of an E-MORB type source in a back-arc extensional setting, whereas trace element contents in intermediate rocks of the Seaspray Cove Formation suggest that they were produced by the low-degree partial melting of a subduction-enriched source in an arc setting. The two formations are separated by a long interval of volcanic quiescence and deep weathering, during which time the back-arc region evolved from extension to shortening and was eventually onlapped by arc volcanic rocks. Based on limited field constraints, paleomagnetic and paleontological data, this progradation of arc onto back-arc volcanic rocks occurred from the north, where an increasingly young Iapetan oceanic plate was being subducted at an increasingly shallow angle. Partial subduction of the Iapetan oceanic ridge is thought to have subsequently generated slab window magmatism, thus marking the last pulse of subduction-related volcanism in both East and West Avalonia.

Evolution of the trace element contents (Sr and Mn) of hemipelagic carbonates from the Zumaia Paleocene section (Gipuzkoa, Spain): implications for the knowledge of seawater chemistry during the Selandian

2014 ◽  
Vol 185 (6) ◽  
pp. 413-435 ◽  
Author(s):  
Laurence Le Callonnec ◽  
Maurice Renard ◽  
Marc De Rafélis ◽  
Fabrice Minoletti ◽  
Catherine Beltran ◽  
...  
Keyword(s):  
Trace Element ◽  
North Atlantic ◽  
Absorption Spectrometry ◽  
Minor Role ◽  
Burial Diagenesis ◽  
The North ◽  
Trace Element Contents ◽  
Mn Content ◽  
The North Atlantic ◽  
Element Contents

AbstractWell exposed and stratigraphically well constrained by numerous studies, the Zumaia section is one of the best places to conduct studies on the Palaeocene in basin facies. Thus, this section has been chosen [Schmitz et al., 2011] as a stratotype of Selandian basal and terminal limits (GSSP: Global boundary Stratotype Section and Point). The sediments consist of carbonate hemipelagites interbedded with fine carbonate (Maastrichtian to Selandian) and siliciclastic (Thanetian to Eocene) turbidites.The purpose of this work is to geochemically characterize the Selandian by trace element contents (strontium and manganese) and to try to assess the chemical composition of seawater during the Paleocene. Analysis of various separated granulometric fine fractions show that hemipelagic sediments from the Zumaia section present a high preservation quality of the original records of trace-element contents. Late burial diagenesis plays only a minor role and geochemical breaks are not reducible to a change in the nature of carbonate producers.The strontium contents of Paleocene sediments require that the Sr/Ca ratio of seawater was lower than that in the present ocean. The Selandian is characterized by a positive excursion of the strontium curve. This accident is also recognized in several worldwide sections and is related to the platform/basin carbonate sedimentation budget and the intensity of oceanic hydrothermalism.The Mn content of hemipelagites is very high and can reach 2500–3000 ppm in the Paleocene. A comparison of analyses by atomic absorption spectrometry (AAS) and electron paramagnetic resonance (EPR) shows that both Mn2+ (in the calcite lattice) and Mn4+ (as oxide micro nodules) coexist. The Mn content fluctuations are related to the opening phases of the North Atlantic during the Paleocene by submarine volcanism and hydrothermalism in the North Atlantic Igneous Province (NAIP).

Trace Element Contents in Thyroid Cancer Investigated by Instrumental Neutron Activation Analysis

2018 ◽  
Vol 1 (1) ◽  
pp. 1-13
Keyword(s):  
Thyroid Cancer ◽  
Neutron Activation Analysis ◽  
Instrumental Neutron Activation Analysis ◽  
Activation Analysis ◽  
Neutron Activation ◽  
Trace Element ◽  
Thyroid Tissue ◽  
Tissue Levels ◽  
Trace Element Contents ◽  
Element Contents

Background: Thyroid cancer is an internationally important health problem. The aim of this exploratory study was to evaluate whether significant changes in the thyroid tissue levels of Ag, Co, Cr, Fe, Hg, Rb, Sb, Sc, Se, and Zn exist in the malignantly transformed thyroid. Methods: Thyroid tissue levels of ten trace elements were prospectively evaluated in 41 patients with thyroid malignant tumors and 105 healthy inhabitants. Measurements were performed using non-destructive instrumental neutron activation analysis with high resolution spectrometry of long-lived radionuclides. Tissue samples were divided into two portions. One was used for morphological study while the other was intended for trace element analysis. Results: It was found that contents of Ag, Co, Cr, Hg, and Rb were significantly higher (approximately 12.8, 1.4, 1.6, 19.6, and 1.7 times, respectively) in cancerous tissues than in normal tissues. Conclusions: There are considerable changes in trace element contents in the malignantly transformed tissue of thyroid.

Trace-Element Contents of Serum, Urine, and Kidney Stones in Urinary Stone Formers

Urolithiasis ◽  
1989 ◽  
pp. 229-231
Author(s):  
J. Hofbauer ◽  
I. Steffan ◽  
H. Schwetz ◽  
G. Vujicic ◽  
O. Zechner
Keyword(s):  
Trace Element ◽  
Kidney Stones ◽  
Urinary Stone ◽  
Stone Formers ◽  
Trace Element Contents ◽  
Element Contents

Environmental assessment of potential toxic trace element contents in the inundated floodplain area of Tablas de Daimiel wetland (Spain)

2016 ◽  
Vol 39 (5) ◽  
pp. 1159-1177 ◽  
Author(s):  
R. Jiménez-Ballesta ◽  
F. J. García-Navarro ◽  
S. Bravo ◽  
J. A. Amorós ◽  
C. Pérez-de-los-Reyes ◽  
...  
Keyword(s):  
Trace Element ◽  
Environmental Assessment ◽  
Trace Element Contents ◽  
Element Contents ◽  
Floodplain Area ◽  
Toxic Trace Element

Assessment of sampling and analytical uncertainty of trace element contents in arable field soils

2011 ◽  
Vol 184 (7) ◽  
pp. 4517-4538 ◽  
Author(s):  
Uwe Buczko ◽  
Rolf O. Kuchenbuch ◽  
Walter Übelhör ◽  
Ludwig Nätscher
Keyword(s):  
Trace Element ◽  
Analytical Uncertainty ◽  
Arable Field ◽  
Field Soils ◽  
Trace Element Contents ◽  
Element Contents

Minor elements in olivine from spinel lherzolite xenoliths: implications for thermobarometry

1997 ◽  
Vol 61 (405) ◽  
pp. 257-269 ◽  
Author(s):  
Suzanne Y. O'Reilly ◽  
D. Chen ◽  
W. L. Griffin ◽  
C. G. Ryan
Keyword(s):  
Trace Element ◽  
Garnet Peridotite ◽  
Spinel Peridotite ◽  
Spinel Lherzolite ◽  
Proton Microprobe ◽  
Minor Elements ◽  
Spinel Lherzolites ◽  
Peridotite Xenoliths ◽  
Trace Element Contents ◽  
Element Contents

AbstractThe proton microprobe has been used to determine contents of Ca, Ti, Ni, Mn and Zn in the olivine of 54 spinel lherzolite xenoliths from Australian and Chinese basalts. These data are compared with proton-probe data for Ni, Mn and Zn in the olivine of 180 garnet peridotite xenoliths from African and Siberian kimberlites. Fe, Mn, Ni and Zn contents are well-correlated; because the spinel lherzolite olivines have higher mean Fe contents than garnet peridotite olivines (average Fo89.6vs. Fo90–92) they also have lower Ni and higher Mn contents. Zn and Fe are well-correlated in garnet peridotite olivine, but in spinel peridotites this relationship is perturbed by partitioning of Zn into spinel. None of these elements shows significant correlation with temperature. Consistent differences in trace-element contents of olivines in the two suites is interpreted as reflecting the greater degree of depletion of Archean garnet peridotites as compared to Phanerozoic spinel lherzolites. Ca and Ti contents of spinel-peridotite olivine are well correlated with one another, and with temperature as determined by several types of geothermometer. However, Ca contents are poorly correlated with pressure as determined by the Ca-in-olivine barometer of Köhler and Brey (1990). This reflects the strong T-dependence of this barometer: the uncertainty in pressure (calculated by this method) which is produced by the ±50°C uncertainty expected of any geothermometer is ca ± 8 kbar, corresponding to the entire width of the spinel-lherzolite field at 900–1200°C.

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