Sentences with phrase «strontium isotope ratios»
Strontium isotope ratios can be measured at the delta ppm level using a medium to high resolution magnetic sector mass spectrometer with multiple fixed collectors and either thermal ionization or inductively coupled plasma as an ion source.
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How well do the strontium isotope ratios fit the theories (of riverine deposits??)
The team examined the neodymium and strontium isotope ratios of the sediments and compared them to the known values for the various geological terranes on land.
«Strontium isotope ratios in rock, soil, groundwater and vegetation vary according to the underlying geology of a region,» the researchers wrote.
Strontium isotope ratios in a D. optatum incisor revealed a repeating pattern.
The second factor was an increase in the weathering of the Appalachian rocks between 462 and 454 million years ago, which is indicated by changes in strontium isotope ratios in Ordovician oceanic rocks (Geology, DOI: 10.1130 / g30152a.1).
They also found that the strontium isotope ratio is a sensitive tracer for selenium contamination, one of the major pollutants of mountaintop mining.
Not exact matches
The ratio of strontium to calcium in a given layer of coral reef — as well as the amount of a heavier isotope of oxygen in the carbonate itself — reflect the temperature in this historical record, but the isotopic information also reveals rainfall.
The ratio of different strontium isotopes varies from place to place, providing clues to where an animal lived.
Knowing that strontium derived from land shows a slightly higher ratio of strontium 87 than strontium derived from hydrothermal circulation, the scientists compared isotopes in each type of barite.
They zeroed in on the ratio of radiogenic strontium isotopes, which are naturally occurring in bedrock.
Strontium isotopes can be found in different ratios among geographic regions depending upon the nature of geologic formation.
Using spectroscopy, stable isotope ratios (carbon, nitrogen and sulphur) were investigated in the collagen of the bones, along with the ratio of strontium to calcium in the bone mineral.
To zero in on the possible cultural interaction, archaeologists Dušan Borić of Cardiff University in the United Kingdom and T. Douglas Price of the University of Wisconsin, Madison, analyzed ratios of isotopes of strontium in the teeth of 153 skeletons from nine sites at the Danube gorges.
The ratio of the isotopes of strontium - 87 and strontium - 86 varies widely in different soils and rocks, and ingested strontium collects in the teeth of children, providing a lifelong signature of where a person grew up.
A mass spectrometer revealed the ratio of two forms, or isotopes, of strontium at the different stages, which can indicate where his drinking water came from when matched to an area's geology.
Analyzing the ratios between two Strontium isotopes, 87Sr and 86Sr, researchers can determine differences from place to place on the landscape so uptake of Strontium over a wide area can be distinguished from uptake over a small area.
The scientists examined surveys of the ratio of strontium to calcium content and heavy oxygen isotopes, both are sensitive recorders of sea surface temperatures past and present.
The group highlighted the added value of measuring paired coral strontium / calcium ratios (Sr / Ca) and oxygen isotope ratios (δ18O), two key proxies for sea surface temperature that are often referred to as paleothermometers (δ18O also reflects sea surface salinity).