An application of cathodoluminescence microscopy to the study of textures and reactions in high-grade marbles from Connemara, Ireland

1989 ◽  
Vol 126 (4) ◽  
pp. 333-337 ◽  
Author(s):  
B. W. D. Yardley ◽  
G. E. Lloyd
Keyword(s):  
Stable Isotope ◽  
Transmitted Light ◽  
Amphibolite Facies ◽  
High Grade ◽  
Large Reduction ◽  
Secondary Porosity ◽  
Wide Range ◽  
Growth Zones ◽  
Isotope Studies ◽  
Western Ireland

AbstractUpper amphibolite facies dolomite and calcite marbles from the Dalradian Connemara Marble Formation of western Ireland display a wide range of textures when viewed in cathodoluminescence that are invisible in transmitted light. Examples observed include growth zones in calcite that appear to represent the infilling of a metamorphic secondary porosity, produced by the large reduction in solid volume accompanying growth of tremolite from dolomite and quartz. Retrograde phenomena are widespread, and include both carbonate pseudomorphs after tremolite and coarse veining, which is in optical continuity with peak metamorphic calcite but otherwise indistinguishable from it. Admixture of such widely differing calcite types may account for scatter in some stable isotope studies of marbles.

scholarly journals Sample acidification effects on carbon and nitrogen stable isotope ratios of macrofauna from a Zostera noltii bed

2013 ◽  
Vol 64 (8) ◽  
pp. 741 ◽  
Author(s):  
Anna-Maria Vafeiadou ◽  
Helena Adão ◽  
Marleen De Troch ◽  
Tom Moens
Keyword(s):  
Stable Isotope ◽  
Single Species ◽  
Zostera Noltii ◽  
Limited Information ◽  
Intertidal Sediments ◽  
Nitrogen Stable Isotope ◽  
Single Class ◽  
Carbon And Nitrogen ◽  
Wide Range ◽  
Isotope Studies

Acidification treatment has been used in most stable isotope studies to eliminate inorganic non-dietary carbon, allowing δ13C measurement of organic carbon needed for trophic studies. Because only limited information about the acidification effects on isotopic ratios exists in the literature, we provide an assessment of such effects for a wide range of benthic macroinvertebrates from estuarine intertidal sediments with sparse Zostera noltii Hornem. vegetation. Our results revealed only few significant δ13C shifts for macrobenthos; however, δ13C decrease after acidification was substantial for several species. We conclude that acidification is not necessary for removing calcium carbonate in a majority of macrobenthos, but we also suggest preliminary testing before deciding it can be omitted. The magnitude of the δ15N shifts was substantial for some species and variability in δ15N values of replicate acidified samples exceeded that of non-acidified samples. Therefore, sample acidification should be avoided for δ15N determination. Moreover, acidification effects vary considerably among species belonging to a single class, rendering generalisations from single-species information potentially spurious.

scholarly journals The mode of occurrence and petrogenesis of the sapphirine-bearing and associated rocks of West Greenland

1969 ◽  
Vol 24 ◽  
pp. 1-44
Author(s):  
R.K Herd ◽  
B.F Windley ◽  
M Ghisler
Keyword(s):  
Granulite Facies ◽  
Limited Range ◽  
Amphibolite Facies ◽  
Ultramafic Rocks ◽  
High Grade ◽  
Granulite Facies Metamorphism ◽  
Wide Range ◽  
Facies Metamorphism ◽  
Mode Of Occurrence ◽  
Anorthosite Complex

Seven occurrences of sapphirine-bearing rocks in the Fiskenæsset region are described in detail. They occur within a chromite-layered anorthosite complex that was metamorphosed by a hornblende-granulite facies metamorphism and then by a cordierite-amphibolite facies metamorphism. They were derived from spinel-layered ultramafic rocks that mostly occur as layers and lenses along the contacts between major metaanorthosite and pyribolite/amphibolite horizons within the complex. There are four types of sapphirine-bearing rocks - enstatite, pargasite, gedrite and phlogopite types, which represent a petrogenetic sequence involving increasing degrees of Si, Ca, K and H2O metasomatism related to shearing and deformation along meta-anorthosite-pyribolite junctions. Their relationship to associated non-sapphirine-bearing rocks is described. Brief mineralogical and petrological data are given for the principal minerals and rocks. In addition, two occurrences in the Sukkertoppen region are described in detail; these are also localised in meta-norite-ultramafic lenses in high grade gneisses. It is concluded that sapphirine is stable within a wide range af pressure and temperature conditions, but within a limited range of chemical environments.

Stable isotope studies in the Salitroso Lake Basin (southern Patagonia, Argentina): assessing diet of Late Holocene hunter-gatherers

2009 ◽  
Vol 19 (2) ◽  
pp. 297-308 ◽  
Author(s):  
A. Tessone ◽  
A. F. Zangrando ◽  
G. Barrientos ◽  
R. Goñi ◽  
H. Panarello ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Late Holocene ◽  
Lake Basin ◽  
Hunter Gatherers ◽  
Southern Patagonia ◽  
Isotope Studies

Effects of development on techniques for calcium stable isotope studies in children

1994 ◽  
Vol 23 (6) ◽  
pp. 357-361 ◽  
Author(s):  
Kimberly O. O'Brien ◽  
Steven A. Abrams
Keyword(s):  
Stable Isotope ◽  
Isotope Studies

scholarly journals Correlation of Metabolic Profiles of Plasma and Cerebrospinal Fluid of High-Grade Glioma Patients

Metabolites ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 133
Author(s):  
Artem D. Rogachev ◽  
Nikolay A. Alemasov ◽  
Vladimir A. Ivanisenko ◽  
Nikita V. Ivanisenko ◽  
Evgeniy V. Gaisler ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Molecular Mechanisms ◽  
High Grade Glioma ◽  
Diagnostic Procedures ◽  
Metabolic Profiles ◽  
High Grade ◽  
Wide Range ◽  
Targeted Screening ◽  
M Estimates ◽  
Metabolite Content

This work compares the metabolic profiles of plasma and the cerebrospinal fluid (CSF) of the patients with high-grade (III and IV) gliomas and the conditionally healthy controls using the wide-range targeted screening of low molecular metabolites by HPLC-MS/MS. The obtained data were analyzed using robust linear regression with Huber’s M-estimates, and a number of metabolites with correlated content in plasma and CSF was identified. The statistical analysis shows a significant correlation of metabolite content in plasma and CSF samples for the majority of metabolites. Several metabolites were shown to have high correlation in the control samples, but not in the glioma patients. This can be due to the specific metabolic processes in the glioma patients or to the damaged integrity of blood-brain barrier. The results of our study may be useful for the understanding of molecular mechanisms underlying the development of gliomas, as well as for the search of potential biomarkers for the minimally invasive diagnostic procedures of gliomas.

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