Lead isotopic fingerprinting of tectono-stratigraphic terranes, east-central Alaska

1987 ◽  
Vol 24 (10) ◽  
pp. 2089-2098 ◽  
Author(s):  
John N. Aleinikoff ◽  
Cynthia Dusel-Bacon ◽  
Helen L. Foster ◽  
Warren J. Nokleberg
Keyword(s):  
Isotopic Composition ◽  
Igneous Rocks ◽  
Isotopic Ratios ◽  
East Central ◽  
Isotopic Compositions ◽  
Common Lead ◽  
Crustal Origin ◽  
Lead Isotopic Ratios ◽  
Isotopic Fingerprinting

Common lead isotopic compositions have been determined on feldspars from meta-igneous rocks from nine tectono-stratigraphic terranes or subterranes in east-central Alaska. Most of the terranes have distinct and well-defined signatures in terms of isotopic composition; thus, most can be distinguished on conventional lead isotopic diagrams. Lead isotopic ratios provide evidence for (1) possible sources for the igneous rocks, (2) time of metamorphism, (3) correlation of terrane fragments, and (4) delineation of juxtaposed terranes. Determination of lead isotopic ratios from igneous rocks can be useful in characterizing tectono-stratigraphic terranes (as to mantle or crustal origin) and in correlation, particularly where terrane relationships are enigmatic.

scholarly journals Measurements of extinct fission products in nuclear bomb debris: Determination of the yield of the Trinity nuclear test 70 y later

2016 ◽  
Vol 113 (29) ◽  
pp. 8104-8108 ◽  
Author(s):  
Susan K. Hanson ◽  
Anthony D. Pollington ◽  
Christopher R. Waidmann ◽  
William S. Kinman ◽  
Allison M. Wende ◽  
...  
Keyword(s):  
Isotopic Composition ◽  
Fission Products ◽  
Nuclear Test ◽  
Isotopic Ratios ◽  
Nuclear Bomb ◽  
Isotopic Compositions ◽  
The Trinity

This paper describes an approach to measuring extinct fission products that would allow for the characterization of a nuclear test at any time. The isotopic composition of molybdenum in five samples of glassy debris from the 1945 Trinity nuclear test has been measured. Nonnatural molybdenum isotopic compositions were observed, reflecting an input from the decay of the short-lived fission products 95Zr and 97Zr. By measuring both the perturbation of the 95Mo/96Mo and 97Mo/96Mo isotopic ratios and the total amount of molybdenum in the Trinity nuclear debris samples, it is possible to calculate the original concentrations of the 95Zr and 97Zr isotopes formed in the nuclear detonation. Together with a determination of the amount of plutonium in the debris, these measurements of extinct fission products allow for new estimates of the efficiency and yield of the historic Trinity test.

Determination of lead isotopic ratios in Greenland and Antarctic snow and ice at picogram per gram concentrations

1995 ◽  
Vol 311 (2) ◽  
pp. 141-151 ◽  
Author(s):  
W. Chisholm ◽  
K.J.R. Rosman ◽  
C.F. Boutron ◽  
J.P. Candelone ◽  
S. Hong
Keyword(s):  
Isotopic Ratios ◽  
Antarctic Snow ◽  
Lead Isotopic Ratios ◽  
Snow And Ice

Alteration of Trace Lead Isotopic Ratios by Postore Metamorphic and Hydrothermal Activity

1973 ◽  
Vol 10 (12) ◽  
pp. 1782-1789 ◽  
Author(s):  
G. L. Cumming ◽  
P. J. Gudjurgis
Keyword(s):  
Isotopic Composition ◽  
Lead Isotope ◽  
Regional Metamorphism ◽  
Hydrothermal Activity ◽  
Isotopic Ratios ◽  
Iron Sulfides ◽  
Ore Body ◽  
Wide Range ◽  
Lead Isotopic Ratios ◽  
Isotope Analyses

Isotope analyses on leads in iron sulfides and trace galenas from two deposits (Big Ledge, British Columbia and Quemont Mine, Quebec) suggest that variations in the isotopic composition may be influenced by postmineralization alteration of ore. It is postulated that when the ore has been subject to regional metamorphism after emplacement, the metamorphism has homogenized the lead isotope ratios throughout the ore body as appears to have happened at Big Ledge, whereas, if postore activity is limited to minor hydrothermal alteration, as at Quemont, then the lead may be left with a wide range of isotopic composition.

Herkunftsbestimmung von Arzneimitteln durch Messung von natürlichen Isotopenverhältnissen: D/H und 13C/12C Verhältnisse einiger Proben von Diazepam / Determination of the Origin of Drugs by Measuring Natural Isotope Contents: D/H and 13C/12C Ratios of Some Diazepam Samples

1976 ◽  
Vol 31 (3-4) ◽  
pp. 111-114 ◽  
Author(s):  
Peter Bommer ◽  
Heribert Moser ◽  
Willibald Stichler ◽  
Peter Trimborn ◽  
Walter Vetter
Keyword(s):  
Isotopic Composition ◽  
Precise Determination ◽  
Commercial Product ◽  
Isotopic Ratios ◽  
Isotopic Abundance ◽  
Natural Isotopic Abundance ◽  
Natural Isotope

Abstract The precise determination of the natural isotopic abundance ratios of carbon and hydrogen in several production batches of the commercial product 7-chlor-1,3-dihydro-1-methyl-5-phenyl-2H-1,4-benzodiazepin-2-on (diazepam) gave results which allowed certain batches to be differentiated. The differences in the ratios appear to be mainly due to differences in the isotopic composition of the (fossile) starting materials of the synthesis. The measurement of the natural isotopic ratios may therefore offer another possibility to deter­ mine the origin of a drug.

scholarly journals Determination of Lead Isotopic Ratios in Original Kosa Soils.

1994 ◽  
Vol 4 (4) ◽  
pp. 863-869
Author(s):  
Hao QUAN ◽  
Yeru HUANG ◽  
Masataka NISHIKAWA ◽  
Masatoshi MORITA
Keyword(s):  
Isotopic Ratios ◽  
Lead Isotopic Ratios

Changes of Ionic and Oxygen Isotopic Composition of the Snowpack at the Glacier Austre Okstindbreen, Norway, 1995

1998 ◽  
Vol 29 (1) ◽  
pp. 1-20 ◽  
Author(s):  
Peter Raben ◽  
Wilfred H. Theakstone
Keyword(s):  
Isotopic Composition ◽  
Sea Level ◽  
Oxygen Isotopes ◽  
Oxygen Isotopic Composition ◽  
Isotopic Ratios ◽  
Vertical Variations ◽  
Oxygen Isotopic ◽  
The Difference ◽  
Liquid Precipitation ◽  
Different Altitudes

Marked vertical variations of ions and oxygen isotopes were present in the snowpack at the glacier Austre Okstindbreen during the pre-melting phase in 1995 at sites between 825 m and 1,470 m above sea level. As the first meltwater percolated from the top of the pack, ions were moved to a greater depth, but the isotopic composition remained relatively unchanged. Ions continued to move downwards through the pack during the melting phase, even when there was little surface melting and no addition of liquid precipitation. The at-a-depth correlation between ionic concentrations and isotopic ratios, strong in the pre-melting phase, weakened during melting. In August, concentrations of Na+ and Mg2+ ions in the residual pack were low and vertical variations were slight; 18O enrichment had occurred. The difference of the time at which melting of the snowpack starts at different altitudes influences the input of ions and isotopes to the underlying glacier.

scholarly journals A single-step purification method for the precise determination of the antimony isotopic composition of environmental, geological and biological samples by HG-MC-ICP-MS

2021 ◽  
Author(s):  
Ferrari Colin ◽  
Resongles Eléonore ◽  
Freydier Rémi ◽  
Casiot Corinne
Keyword(s):  
Isotopic Composition ◽  
Biological Samples ◽  
Precise Determination ◽  
Single Step ◽  
Functionalized Silica ◽  
Purification Method ◽  
Silica Powder ◽  
Icp Ms ◽  
Single Step Purification

Thiol-functionalized silica powder allowed single-step purification of antimony for exploring stable Sb isotope signatures in the environment.

Reconstructing Terrestrial Environments Using Stable Isotopes in Fossil Teeth and Paleosol Carbonates

2012 ◽  
Vol 18 ◽  
pp. 167-194 ◽  
Author(s):  
Benjamin H. Passey
Keyword(s):  
Isotopic Composition ◽  
Soil Temperature ◽  
Carbon Isotopes ◽  
Oxygen Isotopes ◽  
Precipitation Amount ◽  
Radiative Heating ◽  
Mammal Species ◽  
Isotopic Compositions ◽  
Heat Effects ◽  
Oxygen Isotopic

Carbon isotopes in Neogene-age fossil teeth and paleosol carbonates are commonly interpreted in the context of past distributions of C3 and C4 vegetation. These two plant types have very different distributions in relation to climate and ecology, and provide a robust basis for reconstructing terrestrial paleoclimates and paleoenvironments during the Neogene. Carbon isotopes in pre-Neogene fossil teeth are usually interpreted in the context of changes in the δ13C value of atmospheric CO2, and variable climate-dependent carbon-isotope discrimination in C3 plants. Carbon isotopes in pre-Neogene soil carbonates can be used to estimate past levels of atmospheric CO2. Oxygen isotopes in fossil teeth and paleosol carbonates primarily are influenced by the oxygen isotopic compositions of ancient rainfall and surface waters. The oxygen isotopic composition of rainfall is has a complex, but tractable, relationship with climate, and variably relates to temperature, elevation, precipitation amount, and other factors. Mammal species that rely on moisture in dietary plant tissues to satisfy their water requirements (rather than surface drinking water) may have oxygen isotopic compositions that track aridity. Thus, oxygen isotopes of fossil mammals can place broad constraints on paleoaridity. Carbonate clumped isotope thermometry allows for reconstruction of soil temperatures at the time of pedogenic carbonate mineralization. The method is unique because it is the only thermodynamically based isotopic paleothermometer that does not require assumptions about the isotopic composition of the fluid in which the archive mineral formed. Soil temperature reflects a complex interplay of air temperature, solar radiative heating, latent heat effects, soil thermal diffusivity, and seasonal variations of these parameters. Because plants and most animals live in and/or near the soil, soil temperature is an important aspect of terrestrial (paleo)climate.

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